Merge pull request #1 from w0rp/master

update

84 files changed, 1076 insertions, 510 deletions

diff --git a/CODE_OF_CONDUCT.md b/.github/CODE_OF_CONDUCT.md
index 587bb372..587bb372 100644
--- a/CODE_OF_CONDUCT.md
+++ b/.github/CODE_OF_CONDUCT.md
diff --git a/CONTRIBUTING.md b/.github/CONTRIBUTING.md
index e59f8326..e59f8326 100644
--- a/CONTRIBUTING.md
+++ b/.github/CONTRIBUTING.md
diff --git a/PULL_REQUEST_TEMPLATE.md b/.github/PULL_REQUEST_TEMPLATE.md
index 8e1b5c57..8e1b5c57 100644
--- a/PULL_REQUEST_TEMPLATE.md
+++ b/.github/PULL_REQUEST_TEMPLATE.md
diff --git a/.travis.yml b/.travis.yml
index 0f006e4c..d48c1e08 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -3,5 +3,10 @@ sudo: required
 services:
     - docker
 language: generic
+env:
+    - OPTIONS=--vim-80-only
+    - OPTIONS=--vim-81-only
+    - OPTIONS=--neovim-only
+    - OPTIONS=--linters-only
 script: |
-    ./run-tests -v
+    ./run-tests -v $OPTIONS
diff --git a/Dockerfile b/Dockerfile
index 20a43bca..6111f9ba 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,6 +1,7 @@
 FROM tweekmonster/vim-testbed:latest
 
 RUN install_vim -tag v8.0.0027 -build \
+                -tag v8.1.0204 -build \
                 -tag neovim:v0.2.0 -build \
                 -tag neovim:v0.3.0 -build
 
diff --git a/README.md b/README.md
index 26baf76c..66a30bf2 100644
--- a/README.md
+++ b/README.md
@@ -4,7 +4,8 @@
 ![ALE Logo by Mark Grealish - https://www.bhalash.com/](img/logo.jpg?raw=true)
 
 ALE (Asynchronous Lint Engine) is a plugin for providing linting in NeoVim
-0.2.0+ and Vim 8 while you edit your text files.
+0.2.0+ and Vim 8 while you edit your text files, and acts as a Vim
+[Language Server Protocol](https://langserver.org/) client.
 
 ![linting example](img/example.gif?raw=true)
 
@@ -96,7 +97,7 @@ formatting.
 | Awk | [gawk](https://www.gnu.org/software/gawk/)|
 | Bash | [language-server](https://github.com/mads-hartmann/bash-language-server), shell [-n flag](https://www.gnu.org/software/bash/manual/bash.html#index-set), [shellcheck](https://www.shellcheck.net/), [shfmt](https://github.com/mvdan/sh) |
 | Bourne Shell | shell [-n flag](http://linux.die.net/man/1/sh), [shellcheck](https://www.shellcheck.net/), [shfmt](https://github.com/mvdan/sh) |
-| C | [cppcheck](http://cppcheck.sourceforge.net), [cpplint](https://github.com/google/styleguide/tree/gh-pages/cpplint), [clang](http://clang.llvm.org/), [clangtidy](http://clang.llvm.org/extra/clang-tidy/) !!, [clang-format](https://clang.llvm.org/docs/ClangFormat.html), [flawfinder](https://www.dwheeler.com/flawfinder/), [gcc](https://gcc.gnu.org/) |
+| C | [cppcheck](http://cppcheck.sourceforge.net), [cpplint](https://github.com/google/styleguide/tree/gh-pages/cpplint), [clang](http://clang.llvm.org/), [clangd](https://clang.llvm.org/extra/clangd.html), [clangtidy](http://clang.llvm.org/extra/clang-tidy/) !!, [clang-format](https://clang.llvm.org/docs/ClangFormat.html), [flawfinder](https://www.dwheeler.com/flawfinder/), [gcc](https://gcc.gnu.org/) |
 | C++ (filetype cpp) | [clang](http://clang.llvm.org/), [clangcheck](http://clang.llvm.org/docs/ClangCheck.html) !!, [clangtidy](http://clang.llvm.org/extra/clang-tidy/) !!, [clang-format](https://clang.llvm.org/docs/ClangFormat.html), [cppcheck](http://cppcheck.sourceforge.net), [cpplint](https://github.com/google/styleguide/tree/gh-pages/cpplint) !!, [cquery](https://github.com/cquery-project/cquery), [flawfinder](https://www.dwheeler.com/flawfinder/), [gcc](https://gcc.gnu.org/) |
 | CUDA | [nvcc](http://docs.nvidia.com/cuda/cuda-compiler-driver-nvcc/index.html) |
 | C# | [mcs](http://www.mono-project.com/docs/about-mono/languages/csharp/) see:`help ale-cs-mcs` for details, [mcsc](http://www.mono-project.com/docs/about-mono/languages/csharp/) !! see:`help ale-cs-mcsc` for details and configuration|
@@ -118,7 +119,7 @@ formatting.
 | Erb | [erb](https://apidock.com/ruby/ERB), [erubi](https://github.com/jeremyevans/erubi), [erubis](https://github.com/kwatch/erubis) |
 | Erlang | [erlc](http://erlang.org/doc/man/erlc.html), [SyntaxErl](https://github.com/ten0s/syntaxerl) |
 | Fish | fish [-n flag](https://linux.die.net/man/1/fish)
-| Fortran | [gcc](https://gcc.gnu.org/) |
+| Fortran | [gcc](https://gcc.gnu.org/), [language_server](https://github.com/hansec/fortran-language-server) |
 | Fountain | [proselint](http://proselint.com/) |
 | FusionScript | [fusion-lint](https://github.com/RyanSquared/fusionscript) |
 | Git Commit Messages | [gitlint](https://github.com/jorisroovers/gitlint) |
@@ -127,7 +128,7 @@ formatting.
 | GraphQL | [eslint](http://eslint.org/), [gqlint](https://github.com/happylinks/gqlint), [prettier](https://github.com/prettier/prettier) |
 | Haml | [haml-lint](https://github.com/brigade/haml-lint) |
 | Handlebars | [ember-template-lint](https://github.com/rwjblue/ember-template-lint) |
-| Haskell | [brittany](https://github.com/lspitzner/brittany), [ghc](https://www.haskell.org/ghc/), [stack-ghc](https://haskellstack.org/), [stack-build](https://haskellstack.org/) !!, [ghc-mod](https://github.com/DanielG/ghc-mod), [stack-ghc-mod](https://github.com/DanielG/ghc-mod), [hlint](https://hackage.haskell.org/package/hlint), [hdevtools](https://hackage.haskell.org/package/hdevtools), [hfmt](https://github.com/danstiner/hfmt) |
+| Haskell | [brittany](https://github.com/lspitzner/brittany), [ghc](https://www.haskell.org/ghc/), [cabal-ghc](https://www.haskell.org/cabal/), [stack-ghc](https://haskellstack.org/), [stack-build](https://haskellstack.org/) !!, [ghc-mod](https://github.com/DanielG/ghc-mod), [stack-ghc-mod](https://github.com/DanielG/ghc-mod), [hlint](https://hackage.haskell.org/package/hlint), [hdevtools](https://hackage.haskell.org/package/hdevtools), [hfmt](https://github.com/danstiner/hfmt) |
 | HTML | [alex](https://github.com/wooorm/alex) !!, [HTMLHint](http://htmlhint.com/), [proselint](http://proselint.com/), [tidy](http://www.html-tidy.org/), [write-good](https://github.com/btford/write-good) |
 | Idris | [idris](http://www.idris-lang.org/) |
 | Java | [checkstyle](http://checkstyle.sourceforge.net), [javac](http://www.oracle.com/technetwork/java/javase/downloads/index.html), [google-java-format](https://github.com/google/google-java-format), [PMD](https://pmd.github.io/) |
diff --git a/ale_linters/apiblueprint/drafter.vim b/ale_linters/apiblueprint/drafter.vim
index 9cded359..198709f9 100644
--- a/ale_linters/apiblueprint/drafter.vim
+++ b/ale_linters/apiblueprint/drafter.vim
@@ -31,6 +31,6 @@ call ale#linter#Define('apiblueprint', {
 \   'name': 'drafter',
 \   'output_stream': 'stderr',
 \   'executable': 'drafter',
-\   'command': 'drafter --use-line-num --validate %t',
+\   'command': 'drafter --use-line-num --validate',
 \   'callback': 'ale_linters#apiblueprint#drafter#HandleErrors',
 \})
diff --git a/ale_linters/asciidoc/writegood.vim b/ale_linters/asciidoc/writegood.vim
index c986cc6c..a29b7e9c 100644
--- a/ale_linters/asciidoc/writegood.vim
+++ b/ale_linters/asciidoc/writegood.vim
@@ -1,9 +1,4 @@
 " Author: Sumner Evans <sumner.evans98@gmail.com>
 " Description: write-good for AsciiDoc files
 
-call ale#linter#Define('asciidoc', {
-\   'name': 'write-good',
-\   'executable_callback': 'ale#handlers#writegood#GetExecutable',
-\   'command_callback': 'ale#handlers#writegood#GetCommand',
-\   'callback': 'ale#handlers#writegood#Handle',
-\})
+call ale#handlers#writegood#DefineLinter('asciidoc')
diff --git a/ale_linters/c/clangd.vim b/ale_linters/c/clangd.vim
new file mode 100644
index 00000000..5aa2e221
--- /dev/null
+++ b/ale_linters/c/clangd.vim
@@ -0,0 +1,29 @@
+" Author: Andrey Melentyev <andrey.melentyev@protonmail.com>
+" Description: Clangd language server
+
+call ale#Set('c_clangd_executable', 'clangd')
+call ale#Set('c_clangd_options', '')
+
+function! ale_linters#c#clangd#GetProjectRoot(buffer) abort
+    let l:project_root = ale#path#FindNearestFile(a:buffer, 'compile_commands.json')
+    return !empty(l:project_root) ? fnamemodify(l:project_root, ':h') : ''
+endfunction
+
+function! ale_linters#c#clangd#GetExecutable(buffer) abort
+    return ale#Var(a:buffer, 'c_clangd_executable')
+endfunction
+
+function! ale_linters#c#clangd#GetCommand(buffer) abort
+    let l:executable = ale_linters#c#clangd#GetExecutable(a:buffer)
+    let l:options = ale#Var(a:buffer, 'c_clangd_options')
+
+    return ale#Escape(l:executable) . (!empty(l:options) ? ' ' . l:options : '')
+endfunction
+
+call ale#linter#Define('c', {
+\   'name': 'clangd',
+\   'lsp': 'stdio',
+\   'executable_callback': 'ale_linters#c#clangd#GetExecutable',
+\   'command_callback': 'ale_linters#c#clangd#GetCommand',
+\   'project_root_callback': 'ale_linters#c#clangd#GetProjectRoot',
+\})
diff --git a/ale_linters/elixir/dialyxir.vim b/ale_linters/elixir/dialyxir.vim
index 5ef3a047..bba0ae14 100644
--- a/ale_linters/elixir/dialyxir.vim
+++ b/ale_linters/elixir/dialyxir.vim
@@ -28,7 +28,7 @@ endfunction
 call ale#linter#Define('elixir', {
 \   'name': 'dialyxir',
 \   'executable': 'mix',
-\   'command': 'mix dialyzer',
+\   'command': 'mix help dialyzer && mix dialyzer',
 \   'callback': 'ale_linters#elixir#dialyxir#Handle',
 \})
 
diff --git a/ale_linters/fortran/language_server.vim b/ale_linters/fortran/language_server.vim
new file mode 100644
index 00000000..fd763fcf
--- /dev/null
+++ b/ale_linters/fortran/language_server.vim
@@ -0,0 +1,27 @@
+" Author: unpairedbracket ben.spiers22@gmail.com
+" Description: A language server for fortran
+
+call ale#Set('fortran_language_server_executable', 'fortls')
+call ale#Set('fortran_language_server_use_global', get(g:, 'ale_use_global_executables', 0))
+
+function! ale_linters#fortran#language_server#GetExecutable(buffer) abort
+    return ale#Var(a:buffer, 'fortran_language_server_executable')
+endfunction
+
+function! ale_linters#fortran#language_server#GetCommand(buffer) abort
+    return ale#Escape(ale_linters#fortran#language_server#GetExecutable(a:buffer))
+endfunction
+
+function! ale_linters#fortran#language_server#GetProjectRoot(buffer) abort
+    let l:fortls_file = ale#path#FindNearestFile(a:buffer, '.fortls')
+
+    return !empty(l:fortls_file) ? fnamemodify(l:fortls_file, ':h') : ''
+endfunction
+
+call ale#linter#Define('fortran', {
+\   'name': 'language_server',
+\   'lsp': 'stdio',
+\   'executable_callback': 'ale_linters#fortran#language_server#GetExecutable',
+\   'command_callback': 'ale_linters#fortran#language_server#GetCommand',
+\   'project_root_callback': 'ale_linters#fortran#language_server#GetProjectRoot',
+\})
diff --git a/ale_linters/go/gobuild.vim b/ale_linters/go/gobuild.vim
index 068877a3..c4608071 100644
--- a/ale_linters/go/gobuild.vim
+++ b/ale_linters/go/gobuild.vim
@@ -70,7 +70,8 @@ function! ale_linters#go#gobuild#Handler(buffer, lines) abort
 endfunction
 
 call ale#linter#Define('go', {
-\   'name': 'go build',
+\   'name': 'gobuild',
+\   'aliases': ['go build'],
 \   'executable': 'go',
 \   'command_chain': [
 \     {'callback': 'ale_linters#go#gobuild#GoEnv', 'output_stream': 'stdout'},
diff --git a/ale_linters/go/govet.vim b/ale_linters/go/govet.vim
index edf9eb66..e94e6ecd 100644
--- a/ale_linters/go/govet.vim
+++ b/ale_linters/go/govet.vim
@@ -9,7 +9,8 @@ function! ale_linters#go#govet#GetCommand(buffer) abort
 endfunction
 
 call ale#linter#Define('go', {
-\   'name': 'go vet',
+\   'name': 'govet',
+\   'aliases': ['go vet'],
 \   'output_stream': 'stderr',
 \   'executable': 'go',
 \   'command_callback': 'ale_linters#go#govet#GetCommand',
diff --git a/ale_linters/haskell/cabal_ghc.vim b/ale_linters/haskell/cabal_ghc.vim
new file mode 100644
index 00000000..003adf5d
--- /dev/null
+++ b/ale_linters/haskell/cabal_ghc.vim
@@ -0,0 +1,19 @@
+" Author: Eric Wolf <ericwolf42@gmail.com>
+" Description: ghc for Haskell files called with cabal exec
+
+call ale#Set('haskell_cabal_ghc_options', '-fno-code -v0')
+
+function! ale_linters#haskell#cabal_ghc#GetCommand(buffer) abort
+    return 'cabal exec -- ghc '
+    \   . ale#Var(a:buffer, 'haskell_cabal_ghc_options')
+    \   . ' %t'
+endfunction
+
+call ale#linter#Define('haskell', {
+\   'name': 'cabal_ghc',
+\   'aliases': ['cabal-ghc'],
+\   'output_stream': 'stderr',
+\   'executable': 'cabal',
+\   'command_callback': 'ale_linters#haskell#cabal_ghc#GetCommand',
+\   'callback': 'ale#handlers#haskell#HandleGHCFormat',
+\})
diff --git a/ale_linters/haskell/ghc-mod.vim b/ale_linters/haskell/ghc-mod.vim
index 1b15d8c2..eb032f50 100644
--- a/ale_linters/haskell/ghc-mod.vim
+++ b/ale_linters/haskell/ghc-mod.vim
@@ -2,14 +2,16 @@
 " Description: ghc-mod for Haskell files
 
 call ale#linter#Define('haskell', {
-\   'name': 'ghc-mod',
+\   'name': 'ghc_mod',
+\   'aliases': ['ghc-mod'],
 \   'executable': 'ghc-mod',
 \   'command': 'ghc-mod --map-file %s=%t check %s',
 \   'callback': 'ale#handlers#haskell#HandleGHCFormat',
 \})
 
 call ale#linter#Define('haskell', {
-\   'name': 'stack-ghc-mod',
+\   'name': 'stack_ghc_mod',
+\   'aliases': ['stack-ghc-mod'],
 \   'executable': 'stack',
 \   'command': 'stack exec ghc-mod -- --map-file %s=%t check %s',
 \   'callback': 'ale#handlers#haskell#HandleGHCFormat',
diff --git a/ale_linters/haskell/stack_build.vim b/ale_linters/haskell/stack_build.vim
index 44e2e86f..f5bdf4b8 100644
--- a/ale_linters/haskell/stack_build.vim
+++ b/ale_linters/haskell/stack_build.vim
@@ -13,7 +13,8 @@ function! ale_linters#haskell#stack_build#GetCommand(buffer) abort
 endfunction
 
 call ale#linter#Define('haskell', {
-\   'name': 'stack-build',
+\   'name': 'stack_build',
+\   'aliases': ['stack-build'],
 \   'output_stream': 'stderr',
 \   'executable': 'stack',
 \   'command_callback': 'ale_linters#haskell#stack_build#GetCommand',
diff --git a/ale_linters/haskell/stack_ghc.vim b/ale_linters/haskell/stack_ghc.vim
index 0367dc24..d702aa68 100644
--- a/ale_linters/haskell/stack_ghc.vim
+++ b/ale_linters/haskell/stack_ghc.vim
@@ -2,7 +2,8 @@
 " Description: ghc for Haskell files, using Stack
 
 call ale#linter#Define('haskell', {
-\   'name': 'stack-ghc',
+\   'name': 'stack_ghc',
+\   'aliases': ['stack-ghc'],
 \   'output_stream': 'stderr',
 \   'executable': 'stack',
 \   'command': 'stack ghc -- -fno-code -v0 %t',
diff --git a/ale_linters/help/writegood.vim b/ale_linters/help/writegood.vim
index 11254cd2..eeb21a73 100644
--- a/ale_linters/help/writegood.vim
+++ b/ale_linters/help/writegood.vim
@@ -1,9 +1,4 @@
 " Author: Sumner Evans <sumner.evans98@gmail.com>
 " Description: write-good for vim Help files
 
-call ale#linter#Define('help', {
-\   'name': 'write-good',
-\   'executable_callback': 'ale#handlers#writegood#GetExecutable',
-\   'command_callback': 'ale#handlers#writegood#GetCommand',
-\   'callback': 'ale#handlers#writegood#Handle',
-\})
+call ale#handlers#writegood#DefineLinter('help')
diff --git a/ale_linters/html/writegood.vim b/ale_linters/html/writegood.vim
index 9fae8821..6a2bd8e5 100644
--- a/ale_linters/html/writegood.vim
+++ b/ale_linters/html/writegood.vim
@@ -1,9 +1,4 @@
 " Author: Sumner Evans <sumner.evans98@gmail.com>
-" Description: write-good for nroff files
+" Description: write-good for html files
 
-call ale#linter#Define('html', {
-\   'name': 'write-good',
-\   'executable_callback': 'ale#handlers#writegood#GetExecutable',
-\   'command_callback': 'ale#handlers#writegood#GetCommand',
-\   'callback': 'ale#handlers#writegood#Handle',
-\})
+call ale#handlers#writegood#DefineLinter('html')
diff --git a/ale_linters/markdown/remark_lint.vim b/ale_linters/markdown/remark_lint.vim
index 195b0f5a..d9c2efb6 100644
--- a/ale_linters/markdown/remark_lint.vim
+++ b/ale_linters/markdown/remark_lint.vim
@@ -1,3 +1,4 @@
+scriptencoding utf-8
 " Author rhysd https://rhysd.github.io/, Dirk Roorda (dirkroorda), Adrián González Rus (@adrigzr)
 " Description: remark-lint for Markdown files
 call ale#Set('markdown_remark_lint_executable', 'remark')
@@ -43,7 +44,8 @@ function! ale_linters#markdown#remark_lint#Handle(buffer, lines) abort
 endfunction
 
 call ale#linter#Define('markdown', {
-\   'name': 'remark-lint',
+\   'name': 'remark_lint',
+\   'aliases': ['remark-lint'],
 \   'executable_callback': 'ale_linters#markdown#remark_lint#GetExecutable',
 \   'command_callback': 'ale_linters#markdown#remark_lint#GetCommand',
 \   'callback': 'ale_linters#markdown#remark_lint#Handle',
diff --git a/ale_linters/markdown/writegood.vim b/ale_linters/markdown/writegood.vim
index 21dbff1a..7108e7ac 100644
--- a/ale_linters/markdown/writegood.vim
+++ b/ale_linters/markdown/writegood.vim
@@ -1,9 +1,4 @@
 " Author: Sumner Evans <sumner.evans98@gmail.com>
 " Description: write-good for Markdown files
 
-call ale#linter#Define('markdown', {
-\   'name': 'write-good',
-\   'executable_callback': 'ale#handlers#writegood#GetExecutable',
-\   'command_callback': 'ale#handlers#writegood#GetCommand',
-\   'callback': 'ale#handlers#writegood#Handle',
-\})
+call ale#handlers#writegood#DefineLinter('markdown')
diff --git a/ale_linters/nroff/writegood.vim b/ale_linters/nroff/writegood.vim
index d318fb28..bcf344f6 100644
--- a/ale_linters/nroff/writegood.vim
+++ b/ale_linters/nroff/writegood.vim
@@ -1,9 +1,4 @@
 " Author: Sumner Evans <sumner.evans98@gmail.com>
 " Description: write-good for nroff files
 
-call ale#linter#Define('nroff', {
-\   'name': 'write-good',
-\   'executable_callback': 'ale#handlers#writegood#GetExecutable',
-\   'command_callback': 'ale#handlers#writegood#GetCommand',
-\   'callback': 'ale#handlers#writegood#Handle',
-\})
+call ale#handlers#writegood#DefineLinter('nroff')
diff --git a/ale_linters/po/writegood.vim b/ale_linters/po/writegood.vim
index 5a01cb66..14686473 100644
--- a/ale_linters/po/writegood.vim
+++ b/ale_linters/po/writegood.vim
@@ -1,9 +1,4 @@
 " Author: Cian Butler https://github.com/butlerx
 " Description: write-good for PO files
 
-call ale#linter#Define('po', {
-\   'name': 'write-good',
-\   'executable_callback': 'ale#handlers#writegood#GetExecutable',
-\   'command_callback': 'ale#handlers#writegood#GetCommand',
-\   'callback': 'ale#handlers#writegood#Handle',
-\})
+call ale#handlers#writegood#DefineLinter('po')
diff --git a/ale_linters/pod/writegood.vim b/ale_linters/pod/writegood.vim
index 14ed5c0c..9f5461e6 100644
--- a/ale_linters/pod/writegood.vim
+++ b/ale_linters/pod/writegood.vim
@@ -1,9 +1,4 @@
 " Author: Sumner Evans <sumner.evans98@gmail.com>
 " Description: write-good for Pod files
 
-call ale#linter#Define('pod', {
-\   'name': 'write-good',
-\   'executable_callback': 'ale#handlers#writegood#GetExecutable',
-\   'command_callback': 'ale#handlers#writegood#GetCommand',
-\   'callback': 'ale#handlers#writegood#Handle',
-\})
+call ale#handlers#writegood#DefineLinter('pod')
diff --git a/ale_linters/rst/writegood.vim b/ale_linters/rst/writegood.vim
index 12137dbf..26b1152a 100644
--- a/ale_linters/rst/writegood.vim
+++ b/ale_linters/rst/writegood.vim
@@ -1,9 +1,4 @@
 " Author: Sumner Evans <sumner.evans98@gmail.com>
 " Description: write-good for reStructuredText files
 
-call ale#linter#Define('rst', {
-\   'name': 'write-good',
-\   'executable_callback': 'ale#handlers#writegood#GetExecutable',
-\   'command_callback': 'ale#handlers#writegood#GetCommand',
-\   'callback': 'ale#handlers#writegood#Handle',
-\})
+call ale#handlers#writegood#DefineLinter('rst')
diff --git a/ale_linters/sml/smlnj_cm.vim b/ale_linters/sml/smlnj_cm.vim
index 96cd7bd9..7a482307 100644
--- a/ale_linters/sml/smlnj_cm.vim
+++ b/ale_linters/sml/smlnj_cm.vim
@@ -9,7 +9,8 @@ endfunction
 " Using CM requires that we set "lint_file: 1", since it reads the files
 " from the disk itself.
 call ale#linter#Define('sml', {
-\   'name': 'smlnj-cm',
+\   'name': 'smlnj_cm',
+\   'aliases': ['smlnj-cm'],
 \   'executable_callback': 'ale#handlers#sml#GetExecutableSmlnjCm',
 \   'lint_file': 1,
 \   'command_callback': 'ale_linters#sml#smlnj_cm#GetCommand',
diff --git a/ale_linters/tex/writegood.vim b/ale_linters/tex/writegood.vim
index dc59de2e..c1aeace9 100644
--- a/ale_linters/tex/writegood.vim
+++ b/ale_linters/tex/writegood.vim
@@ -1,9 +1,4 @@
 " Author: Sumner Evans <sumner.evans98@gmail.com>
 " Description: write-good for TeX files
 
-call ale#linter#Define('tex', {
-\   'name': 'write-good',
-\   'executable_callback': 'ale#handlers#writegood#GetExecutable',
-\   'command_callback': 'ale#handlers#writegood#GetCommand',
-\   'callback': 'ale#handlers#writegood#Handle',
-\})
+call ale#handlers#writegood#DefineLinter('tex')
diff --git a/ale_linters/texinfo/writegood.vim b/ale_linters/texinfo/writegood.vim
index 8104c634..4427f056 100644
--- a/ale_linters/texinfo/writegood.vim
+++ b/ale_linters/texinfo/writegood.vim
@@ -1,9 +1,4 @@
 " Author: Sumner Evans <sumner.evans98@gmail.com>
 " Description: write-good for Texinfo files
 
-call ale#linter#Define('texinfo', {
-\   'name': 'write-good',
-\   'executable_callback': 'ale#handlers#writegood#GetExecutable',
-\   'command_callback': 'ale#handlers#writegood#GetCommand',
-\   'callback': 'ale#handlers#writegood#Handle',
-\})
+call ale#handlers#writegood#DefineLinter('texinfo')
diff --git a/ale_linters/text/writegood.vim b/ale_linters/text/writegood.vim
index ff76ce42..81b935d4 100644
--- a/ale_linters/text/writegood.vim
+++ b/ale_linters/text/writegood.vim
@@ -1,9 +1,4 @@
 " Author: Sumner Evans <sumner.evans98@gmail.com>
 " Description: write-good for text files
 
-call ale#linter#Define('text', {
-\   'name': 'write-good',
-\   'executable_callback': 'ale#handlers#writegood#GetExecutable',
-\   'command_callback': 'ale#handlers#writegood#GetCommand',
-\   'callback': 'ale#handlers#writegood#Handle',
-\})
+call ale#handlers#writegood#DefineLinter('text')
diff --git a/ale_linters/xhtml/writegood.vim b/ale_linters/xhtml/writegood.vim
index 83d1863b..1fcba182 100644
--- a/ale_linters/xhtml/writegood.vim
+++ b/ale_linters/xhtml/writegood.vim
@@ -1,9 +1,4 @@
 " Author: Sumner Evans <sumner.evans98@gmail.com>
 " Description: write-good for XHTML files
 
-call ale#linter#Define('xhtml', {
-\   'name': 'write-good',
-\   'executable_callback': 'ale#handlers#writegood#GetExecutable',
-\   'command_callback': 'ale#handlers#writegood#GetCommand',
-\   'callback': 'ale#handlers#writegood#Handle',
-\})
+call ale#handlers#writegood#DefineLinter('xhtml')
diff --git a/autoload/ale.vim b/autoload/ale.vim
index 26c73547..6d1e8521 100644
--- a/autoload/ale.vim
+++ b/autoload/ale.vim
@@ -192,12 +192,7 @@ endfunction
 " Every variable name will be prefixed with 'ale_'.
 function! ale#Var(buffer, variable_name) abort
     let l:full_name = 'ale_' . a:variable_name
-    let l:vars = getbufvar(str2nr(a:buffer), '', 0)
-
-    if l:vars is 0
-        " Look for variables from deleted buffers, saved from :ALEFix
-        let l:vars = get(get(g:ale_fix_buffer_data, a:buffer, {}), 'vars', {})
-    endif
+    let l:vars = getbufvar(str2nr(a:buffer), '', {})
 
     return get(l:vars, l:full_name, g:[l:full_name])
 endfunction
diff --git a/autoload/ale/balloon.vim b/autoload/ale/balloon.vim
index 7a380da2..72f6b91c 100644
--- a/autoload/ale/balloon.vim
+++ b/autoload/ale/balloon.vim
@@ -34,26 +34,25 @@ function! ale#balloon#Expr() abort
 endfunction
 
 function! ale#balloon#Disable() abort
+    if has('balloon_eval')
+        set noballooneval
+        set balloonexpr=
+    endif
+
     if has('balloon_eval_term')
         set noballoonevalterm
+        set balloonexpr=
     endif
-
-    set noballooneval
-    set balloonexpr=
 endfunction
 
 function! ale#balloon#Enable() abort
-    if !has('balloon_eval') && !has('balloon_eval_term')
-        return
-    endif
-
     if has('balloon_eval')
         set ballooneval
+        set balloonexpr=ale#balloon#Expr()
     endif
 
     if has('balloon_eval_term')
         set balloonevalterm
+        set balloonexpr=ale#balloon#Expr()
     endif
-
-    set balloonexpr=ale#balloon#Expr()
 endfunction
diff --git a/autoload/ale/c.vim b/autoload/ale/c.vim
index 5ab10f00..fbfe9509 100644
--- a/autoload/ale/c.vim
+++ b/autoload/ale/c.vim
@@ -4,8 +4,11 @@
 call ale#Set('c_parse_makefile', 0)
 let s:sep = has('win32') ? '\' : '/'
 
+" Set just so tests can override it.
+let g:__ale_c_project_filenames = ['.git/HEAD', 'configure', 'Makefile', 'CMakeLists.txt']
+
 function! ale#c#FindProjectRoot(buffer) abort
-    for l:project_filename in ['.git/HEAD', 'configure', 'Makefile', 'CMakeLists.txt']
+    for l:project_filename in g:__ale_c_project_filenames
         let l:full_path = ale#path#FindNearestFile(a:buffer, l:project_filename)
 
         if !empty(l:full_path)
diff --git a/autoload/ale/completion.vim b/autoload/ale/completion.vim
index e7da4028..7440f8cd 100644
--- a/autoload/ale/completion.vim
+++ b/autoload/ale/completion.vim
@@ -336,7 +336,9 @@ function! ale#completion#ParseLSPCompletions(response) abort
         endif
 
         " See :help complete-items for Vim completion kinds
-        if l:item.kind is s:LSP_COMPLETION_METHOD_KIND
+        if !has_key(l:item, 'kind')
+            let l:kind = 'v'
+        elseif l:item.kind is s:LSP_COMPLETION_METHOD_KIND
             let l:kind = 'm'
         elseif l:item.kind is s:LSP_COMPLETION_CONSTRUCTOR_KIND
             let l:kind = 'm'
@@ -422,54 +424,65 @@ endfunction
 
 function! s:GetLSPCompletions(linter) abort
     let l:buffer = bufnr('')
-    let l:Callback = a:linter.lsp is# 'tsserver'
-    \   ? function('ale#completion#HandleTSServerResponse')
-    \   : function('ale#completion#HandleLSPResponse')
-
-    let l:lsp_details = ale#lsp_linter#StartLSP(l:buffer, a:linter, l:Callback)
+    let l:lsp_details = ale#lsp_linter#StartLSP(l:buffer, a:linter)
 
     if empty(l:lsp_details)
         return 0
     endif
 
     let l:id = l:lsp_details.connection_id
+    let l:root = l:lsp_details.project_root
 
-    if a:linter.lsp is# 'tsserver'
-        let l:message = ale#lsp#tsserver_message#Completions(
-        \   l:buffer,
-        \   b:ale_completion_info.line,
-        \   b:ale_completion_info.column,
-        \   b:ale_completion_info.prefix,
-        \)
-    else
-        " Send a message saying the buffer has changed first, otherwise
-        " completions won't know what text is nearby.
-        call ale#lsp#NotifyForChanges(l:lsp_details)
-
-        " For LSP completions, we need to clamp the column to the length of
-        " the line. python-language-server and perhaps others do not implement
-        " this correctly.
-        let l:message = ale#lsp#message#Completion(
-        \   l:buffer,
-        \   b:ale_completion_info.line,
-        \   min([
-        \       b:ale_completion_info.line_length,
-        \       b:ale_completion_info.column,
-        \   ]),
-        \   ale#completion#GetTriggerCharacter(&filetype, b:ale_completion_info.prefix),
-        \)
-    endif
+    function! OnReady(...) abort closure
+        " If we have sent a completion request already, don't send another.
+        if b:ale_completion_info.request_id
+            return
+        endif
 
-    let l:request_id = ale#lsp#Send(l:id, l:message, l:lsp_details.project_root)
+        let l:Callback = a:linter.lsp is# 'tsserver'
+        \   ? function('ale#completion#HandleTSServerResponse')
+        \   : function('ale#completion#HandleLSPResponse')
+        call ale#lsp#RegisterCallback(l:id, l:Callback)
+
+        if a:linter.lsp is# 'tsserver'
+            let l:message = ale#lsp#tsserver_message#Completions(
+            \   l:buffer,
+            \   b:ale_completion_info.line,
+            \   b:ale_completion_info.column,
+            \   b:ale_completion_info.prefix,
+            \)
+        else
+            " Send a message saying the buffer has changed first, otherwise
+            " completions won't know what text is nearby.
+            call ale#lsp#NotifyForChanges(l:id, l:root, l:buffer)
+
+            " For LSP completions, we need to clamp the column to the length of
+            " the line. python-language-server and perhaps others do not implement
+            " this correctly.
+            let l:message = ale#lsp#message#Completion(
+            \   l:buffer,
+            \   b:ale_completion_info.line,
+            \   min([
+            \       b:ale_completion_info.line_length,
+            \       b:ale_completion_info.column,
+            \   ]),
+            \   ale#completion#GetTriggerCharacter(&filetype, b:ale_completion_info.prefix),
+            \)
+        endif
 
-    if l:request_id
-        let b:ale_completion_info.conn_id = l:id
-        let b:ale_completion_info.request_id = l:request_id
+        let l:request_id = ale#lsp#Send(l:id, l:message, l:lsp_details.project_root)
 
-        if has_key(a:linter, 'completion_filter')
-            let b:ale_completion_info.completion_filter = a:linter.completion_filter
+        if l:request_id
+            let b:ale_completion_info.conn_id = l:id
+            let b:ale_completion_info.request_id = l:request_id
+
+            if has_key(a:linter, 'completion_filter')
+                let b:ale_completion_info.completion_filter = a:linter.completion_filter
+            endif
         endif
-    endif
+    endfunction
+
+    call ale#lsp#WaitForCapability(l:id, l:root, 'completion', function('OnReady'))
 endfunction
 
 function! ale#completion#GetCompletions() abort
diff --git a/autoload/ale/definition.vim b/autoload/ale/definition.vim
index 6c70b64c..6c7d7d32 100644
--- a/autoload/ale/definition.vim
+++ b/autoload/ale/definition.vim
@@ -60,43 +60,50 @@ endfunction
 function! s:GoToLSPDefinition(linter, options) abort
     let l:buffer = bufnr('')
     let [l:line, l:column] = getcurpos()[1:2]
+    let l:lsp_details = ale#lsp_linter#StartLSP(l:buffer, a:linter)
 
-    let l:Callback = a:linter.lsp is# 'tsserver'
-    \   ? function('ale#definition#HandleTSServerResponse')
-    \   : function('ale#definition#HandleLSPResponse')
-
-    let l:lsp_details = ale#lsp_linter#StartLSP(l:buffer, a:linter, l:Callback)
+    if a:linter.lsp isnot# 'tsserver'
+        let l:column = min([l:column, len(getline(l:line))])
+    endif
 
     if empty(l:lsp_details)
         return 0
     endif
 
     let l:id = l:lsp_details.connection_id
+    let l:root = l:lsp_details.project_root
+
+    function! OnReady(...) abort closure
+        let l:Callback = a:linter.lsp is# 'tsserver'
+        \   ? function('ale#definition#HandleTSServerResponse')
+        \   : function('ale#definition#HandleLSPResponse')
+        call ale#lsp#RegisterCallback(l:id, l:Callback)
+
+        if a:linter.lsp is# 'tsserver'
+            let l:message = ale#lsp#tsserver_message#Definition(
+            \   l:buffer,
+            \   l:line,
+            \   l:column
+            \)
+        else
+            " Send a message saying the buffer has changed first, or the
+            " definition position probably won't make sense.
+            call ale#lsp#NotifyForChanges(l:id, l:root, l:buffer)
+
+            " For LSP completions, we need to clamp the column to the length of
+            " the line. python-language-server and perhaps others do not implement
+            " this correctly.
+            let l:message = ale#lsp#message#Definition(l:buffer, l:line, l:column)
+        endif
 
-    if a:linter.lsp is# 'tsserver'
-        let l:message = ale#lsp#tsserver_message#Definition(
-        \   l:buffer,
-        \   l:line,
-        \   l:column
-        \)
-    else
-        " Send a message saying the buffer has changed first, or the
-        " definition position probably won't make sense.
-        call ale#lsp#NotifyForChanges(l:lsp_details)
-
-        let l:column = min([l:column, len(getline(l:line))])
-
-        " For LSP completions, we need to clamp the column to the length of
-        " the line. python-language-server and perhaps others do not implement
-        " this correctly.
-        let l:message = ale#lsp#message#Definition(l:buffer, l:line, l:column)
-    endif
+        let l:request_id = ale#lsp#Send(l:id, l:message, l:lsp_details.project_root)
 
-    let l:request_id = ale#lsp#Send(l:id, l:message, l:lsp_details.project_root)
+        let s:go_to_definition_map[l:request_id] = {
+        \   'open_in_tab': get(a:options, 'open_in_tab', 0),
+        \}
+    endfunction
 
-    let s:go_to_definition_map[l:request_id] = {
-    \   'open_in_tab': get(a:options, 'open_in_tab', 0),
-    \}
+    call ale#lsp#WaitForCapability(l:id, l:root, 'definition', function('OnReady'))
 endfunction
 
 function! ale#definition#GoTo(options) abort
diff --git a/autoload/ale/fix.vim b/autoload/ale/fix.vim
index 62674b87..8dfdeca8 100644
--- a/autoload/ale/fix.vim
+++ b/autoload/ale/fix.vim
@@ -420,9 +420,7 @@ function! ale#fix#InitBufferData(buffer, fixing_flag) abort
     " The 'done' flag tells the function for applying changes when fixing
     " is complete.
     let g:ale_fix_buffer_data[a:buffer] = {
-    \   'vars': getbufvar(a:buffer, ''),
     \   'lines_before': getbufline(a:buffer, 1, '$'),
-    \   'filename': expand('#' . a:buffer . ':p'),
     \   'done': 0,
     \   'should_save': a:fixing_flag is# 'save_file',
     \   'temporary_directory_list': [],
diff --git a/autoload/ale/handlers/writegood.vim b/autoload/ale/handlers/writegood.vim
index aee7c4de..aff66d5f 100644
--- a/autoload/ale/handlers/writegood.vim
+++ b/autoload/ale/handlers/writegood.vim
@@ -59,3 +59,14 @@ function! ale#handlers#writegood#Handle(buffer, lines) abort
 
     return l:output
 endfunction
+
+" Define the writegood linter for a given filetype.
+function! ale#handlers#writegood#DefineLinter(filetype) abort
+    call ale#linter#Define(a:filetype, {
+    \   'name': 'writegood',
+    \   'aliases': ['write-good'],
+    \   'executable_callback': 'ale#handlers#writegood#GetExecutable',
+    \   'command_callback': 'ale#handlers#writegood#GetCommand',
+    \   'callback': 'ale#handlers#writegood#Handle',
+    \})
+endfunction
diff --git a/autoload/ale/hover.vim b/autoload/ale/hover.vim
index 6d131adc..5e97e16e 100644
--- a/autoload/ale/hover.vim
+++ b/autoload/ale/hover.vim
@@ -93,45 +93,51 @@ function! ale#hover#HandleLSPResponse(conn_id, response) abort
 endfunction
 
 function! s:ShowDetails(linter, buffer, line, column, opt) abort
-    let l:Callback = a:linter.lsp is# 'tsserver'
-    \   ? function('ale#hover#HandleTSServerResponse')
-    \   : function('ale#hover#HandleLSPResponse')
-
-    let l:lsp_details = ale#lsp_linter#StartLSP(a:buffer, a:linter, l:Callback)
+    let l:lsp_details = ale#lsp_linter#StartLSP(a:buffer, a:linter)
 
     if empty(l:lsp_details)
         return 0
     endif
 
     let l:id = l:lsp_details.connection_id
+    let l:root = l:lsp_details.project_root
     let l:language_id = l:lsp_details.language_id
 
-    if a:linter.lsp is# 'tsserver'
-        let l:column = a:column
+    function! OnReady(...) abort closure
+        let l:Callback = a:linter.lsp is# 'tsserver'
+        \   ? function('ale#hover#HandleTSServerResponse')
+        \   : function('ale#hover#HandleLSPResponse')
+        call ale#lsp#RegisterCallback(l:id, l:Callback)
 
-        let l:message = ale#lsp#tsserver_message#Quickinfo(
-        \   a:buffer,
-        \   a:line,
-        \   l:column
-        \)
-    else
-        " Send a message saying the buffer has changed first, or the
-        " hover position probably won't make sense.
-        call ale#lsp#NotifyForChanges(l:lsp_details)
+        if a:linter.lsp is# 'tsserver'
+            let l:column = a:column
 
-        let l:column = min([a:column, len(getbufline(a:buffer, a:line)[0])])
+            let l:message = ale#lsp#tsserver_message#Quickinfo(
+            \   a:buffer,
+            \   a:line,
+            \   l:column
+            \)
+        else
+            " Send a message saying the buffer has changed first, or the
+            " hover position probably won't make sense.
+            call ale#lsp#NotifyForChanges(l:id, l:root, a:buffer)
 
-        let l:message = ale#lsp#message#Hover(a:buffer, a:line, l:column)
-    endif
+            let l:column = min([a:column, len(getbufline(a:buffer, a:line)[0])])
+
+            let l:message = ale#lsp#message#Hover(a:buffer, a:line, l:column)
+        endif
+
+        let l:request_id = ale#lsp#Send(l:id, l:message, l:lsp_details.project_root)
 
-    let l:request_id = ale#lsp#Send(l:id, l:message, l:lsp_details.project_root)
+        let s:hover_map[l:request_id] = {
+        \   'buffer': a:buffer,
+        \   'line': a:line,
+        \   'column': l:column,
+        \   'hover_from_balloonexpr': get(a:opt, 'called_from_balloonexpr', 0),
+        \}
+    endfunction
 
-    let s:hover_map[l:request_id] = {
-    \   'buffer': a:buffer,
-    \   'line': a:line,
-    \   'column': l:column,
-    \   'hover_from_balloonexpr': get(a:opt, 'called_from_balloonexpr', 0),
-    \}
+    call ale#lsp#WaitForCapability(l:id, l:root, 'hover', function('OnReady'))
 endfunction
 
 " Obtain Hover information for the specified position
diff --git a/autoload/ale/lsp.vim b/autoload/ale/lsp.vim
index e44b5bc3..312319ab 100644
--- a/autoload/ale/lsp.vim
+++ b/autoload/ale/lsp.vim
@@ -15,13 +15,23 @@ function! ale#lsp#NewConnection(initialization_options) abort
     " open_documents: A Dictionary mapping buffers to b:changedtick, keeping
     "   track of when documents were opened, and when we last changed them.
     " callback_list: A list of callbacks for handling LSP responses.
+    " initialization_options: Options to send to the server.
+    " capabilities: Features the server supports.
     let l:conn = {
+    \   'is_tsserver': 0,
     \   'id': '',
     \   'data': '',
     \   'projects': {},
     \   'open_documents': {},
     \   'callback_list': [],
     \   'initialization_options': a:initialization_options,
+    \   'capabilities': {
+    \       'hover': 0,
+    \       'references': 0,
+    \       'completion': 0,
+    \       'completion_trigger_characters': [],
+    \       'definition': 0,
+    \   },
     \}
 
     call add(s:connections, l:conn)
@@ -44,6 +54,11 @@ function! s:FindConnection(key, value) abort
     return {}
 endfunction
 
+" Get the capabilities for a connection, or an empty Dictionary.
+function! ale#lsp#GetConnectionCapabilities(id) abort
+    return get(s:FindConnection('id', a:id), 'capabilities', {})
+endfunction
+
 function! ale#lsp#GetNextMessageID() abort
     " Use the current ID
     let l:id = g:ale_lsp_next_message_id
@@ -174,6 +189,16 @@ function! s:MarkProjectAsInitialized(conn, project) abort
 
     " Remove the messages now.
     let a:conn.message_queue = []
+
+    " Call capabilities callbacks queued for the project.
+    for [l:capability, l:Callback] in a:project.capabilities_queue
+        if a:conn.is_tsserver || a:conn.capabilities[l:capability]
+            call call(l:Callback, [a:conn.id, a:project.root])
+        endif
+    endfor
+
+    " Clear the queued callbacks now.
+    let a:project.capabilities_queue = []
 endfunction
 
 function! s:HandleInitializeResponse(conn, response) abort
@@ -185,6 +210,38 @@ function! s:HandleInitializeResponse(conn, response) abort
     endif
 endfunction
 
+" Update capabilities from the server, so we know which features the server
+" supports.
+function! s:UpdateCapabilities(conn, capabilities) abort
+    if type(a:capabilities) != type({})
+        return
+    endif
+
+    if get(a:capabilities, 'hoverProvider') is v:true
+        let a:conn.capabilities.hover = 1
+    endif
+
+    if get(a:capabilities, 'referencesProvider') is v:true
+        let a:conn.capabilities.references = 1
+    endif
+
+    if !empty(get(a:capabilities, 'completionProvider'))
+        let a:conn.capabilities.completion = 1
+    endif
+
+    if type(get(a:capabilities, 'completionProvider')) is type({})
+        let l:chars = get(a:capabilities.completionProvider, 'triggerCharacters')
+
+        if type(l:chars) is type([])
+            let a:conn.capabilities.completion_trigger_characters = l:chars
+        endif
+    endif
+
+    if get(a:capabilities, 'definitionProvider') is v:true
+        let a:conn.capabilities.definition = 1
+    endif
+endfunction
+
 function! ale#lsp#HandleOtherInitializeResponses(conn, response) abort
     let l:uninitialized_projects = []
 
@@ -200,6 +257,8 @@ function! ale#lsp#HandleOtherInitializeResponses(conn, response) abort
 
     if get(a:response, 'method', '') is# ''
         if has_key(get(a:response, 'result', {}), 'capabilities')
+            call s:UpdateCapabilities(a:conn, a:response.result.capabilities)
+
             for [l:dir, l:project] in l:uninitialized_projects
                 call s:MarkProjectAsInitialized(a:conn, l:project)
             endfor
@@ -254,22 +313,43 @@ function! s:HandleCommandMessage(job_id, message) abort
     call ale#lsp#HandleMessage(l:conn, a:message)
 endfunction
 
-function! ale#lsp#RegisterProject(conn, project_root) abort
+" Given a connection ID, mark it as a tsserver connection, so it will be
+" handled that way.
+function! ale#lsp#MarkConnectionAsTsserver(conn_id) abort
+    let l:conn = s:FindConnection('id', a:conn_id)
+
+    if !empty(l:conn)
+        let l:conn.is_tsserver = 1
+    endif
+endfunction
+
+" Register a project for an LSP connection.
+"
+" This function will throw if the connection doesn't exist.
+function! ale#lsp#RegisterProject(conn_id, project_root) abort
+    let l:conn = s:FindConnection('id', a:conn_id)
+
     " Empty strings can't be used for Dictionary keys in NeoVim, due to E713.
     " This appears to be a nonsensical bug in NeoVim.
     let l:key = empty(a:project_root) ? '<<EMPTY>>' : a:project_root
 
-    if !has_key(a:conn.projects, l:key)
+    if !has_key(l:conn.projects, l:key)
         " Tools without project roots are ready right away, like tsserver.
-        let a:conn.projects[l:key] = {
+        let l:conn.projects[l:key] = {
+        \   'root': a:project_root,
         \   'initialized': empty(a:project_root),
         \   'init_request_id': 0,
         \   'message_queue': [],
+        \   'capabilities_queue': [],
         \}
     endif
 endfunction
 
 function! ale#lsp#GetProject(conn, project_root) abort
+    if empty(a:conn)
+        return {}
+    endif
+
     let l:key = empty(a:project_root) ? '<<EMPTY>>' : a:project_root
 
     return get(a:conn.projects, l:key, {})
@@ -279,7 +359,7 @@ endfunction
 "
 " The job ID will be returned for for the program if it ran, otherwise
 " 0 will be returned.
-function! ale#lsp#StartProgram(executable, command, project_root, callback, initialization_options) abort
+function! ale#lsp#StartProgram(executable, command, init_options) abort
     if !executable(a:executable)
         return 0
     endif
@@ -287,7 +367,7 @@ function! ale#lsp#StartProgram(executable, command, project_root, callback, init
     let l:conn = s:FindConnection('executable', a:executable)
 
     " Get the current connection or a new one.
-    let l:conn = !empty(l:conn) ? l:conn : ale#lsp#NewConnection(a:initialization_options)
+    let l:conn = !empty(l:conn) ? l:conn : ale#lsp#NewConnection(a:init_options)
     let l:conn.executable = a:executable
 
     if !has_key(l:conn, 'id') || !ale#job#IsRunning(l:conn.id)
@@ -305,18 +385,15 @@ function! ale#lsp#StartProgram(executable, command, project_root, callback, init
     endif
 
     let l:conn.id = l:job_id
-    " Add the callback to the List if it's not there already.
-    call uniq(sort(add(l:conn.callback_list, a:callback)))
-    call ale#lsp#RegisterProject(l:conn, a:project_root)
 
     return l:job_id
 endfunction
 
 " Connect to an address and set up a callback for handling responses.
-function! ale#lsp#ConnectToAddress(address, project_root, callback, initialization_options) abort
+function! ale#lsp#ConnectToAddress(address, init_options) abort
     let l:conn = s:FindConnection('id', a:address)
     " Get the current connection or a new one.
-    let l:conn = !empty(l:conn) ? l:conn : ale#lsp#NewConnection(a:initialization_options)
+    let l:conn = !empty(l:conn) ? l:conn : ale#lsp#NewConnection(a:init_options)
 
     if !has_key(l:conn, 'channel_id') || !ale#socket#IsOpen(l:conn.channel_id)
         let l:conn.channel_id = ale#socket#Open(a:address, {
@@ -329,13 +406,21 @@ function! ale#lsp#ConnectToAddress(address, project_root, callback, initializati
     endif
 
     let l:conn.id = a:address
-    " Add the callback to the List if it's not there already.
-    call uniq(sort(add(l:conn.callback_list, a:callback)))
-    call ale#lsp#RegisterProject(l:conn, a:project_root)
 
     return a:address
 endfunction
 
+" Given a connection ID and a callback, register that callback for handling
+" messages if the connection exists.
+function! ale#lsp#RegisterCallback(conn_id, callback) abort
+    let l:conn = s:FindConnection('id', a:conn_id)
+
+    if !empty(l:conn)
+        " Add the callback to the List if it's not there already.
+        call uniq(sort(add(l:conn.callback_list, a:callback)))
+    endif
+endfunction
+
 " Stop all LSP connections, closing all jobs and channels, and removing any
 " queued messages.
 function! ale#lsp#StopAll() abort
@@ -373,11 +458,6 @@ function! ale#lsp#Send(conn_id, message, ...) abort
     let l:project_root = get(a:000, 0, '')
 
     let l:conn = s:FindConnection('id', a:conn_id)
-
-    if empty(l:conn)
-        return 0
-    endif
-
     let l:project = ale#lsp#GetProject(l:conn, l:project_root)
 
     if empty(l:project)
@@ -411,45 +491,22 @@ function! ale#lsp#Send(conn_id, message, ...) abort
     return l:id == 0 ? -1 : l:id
 endfunction
 
-" The Document details Dictionary should contain the following keys.
-"
-"  buffer - The buffer number for the document.
-"  connection_id - The connection ID for the LSP server.
-"  command - The command to run to start the LSP connection.
-"  project_root - The project root for the LSP project.
-"  language_id - The language ID for the project, like 'python', 'rust', etc.
-
-" Create a new Dictionary containing more connection details, with the
-" following information added:
-"
-"   conn - An existing LSP connection for the document.
-"   document_open - 1 if the document is currently open, 0 otherwise.
-function! s:ExtendDocumentDetails(details) abort
-    let l:extended = copy(a:details)
-    let l:conn = s:FindConnection('id', a:details.connection_id)
-
-    let l:extended.conn = l:conn
-    let l:extended.document_open = !empty(l:conn)
-    \   && has_key(l:conn.open_documents, a:details.buffer)
-
-    return l:extended
-endfunction
-
 " Notify LSP servers or tsserver if a document is opened, if needed.
 " If a document is opened, 1 will be returned, otherwise 0 will be returned.
-function! ale#lsp#OpenDocument(basic_details) abort
-    let l:d = s:ExtendDocumentDetails(a:basic_details)
+function! ale#lsp#OpenDocument(conn_id, project_root, buffer, language_id) abort
+    let l:conn = s:FindConnection('id', a:conn_id)
     let l:opened = 0
 
-    if !empty(l:d.conn) && !l:d.document_open
-        if empty(l:d.language_id)
-            let l:message = ale#lsp#tsserver_message#Open(l:d.buffer)
+    " FIXME: Return 1 if the document is already open?
+    if !empty(l:conn) && !has_key(l:conn.open_documents, a:buffer)
+        if l:conn.is_tsserver
+            let l:message = ale#lsp#tsserver_message#Open(a:buffer)
         else
-            let l:message = ale#lsp#message#DidOpen(l:d.buffer, l:d.language_id)
+            let l:message = ale#lsp#message#DidOpen(a:buffer, a:language_id)
         endif
 
-        call ale#lsp#Send(l:d.connection_id, l:message, l:d.project_root)
-        let l:d.conn.open_documents[l:d.buffer] = getbufvar(l:d.buffer, 'changedtick')
+        call ale#lsp#Send(a:conn_id, l:message, a:project_root)
+        let l:conn.open_documents[a:buffer] = getbufvar(a:buffer, 'changedtick')
         let l:opened = 1
     endif
 
@@ -458,25 +515,50 @@ endfunction
 
 " Notify LSP servers or tsserver that a document has changed, if needed.
 " If a notification is sent, 1 will be returned, otherwise 0 will be returned.
-function! ale#lsp#NotifyForChanges(basic_details) abort
-    let l:d = s:ExtendDocumentDetails(a:basic_details)
+function! ale#lsp#NotifyForChanges(conn_id, project_root, buffer) abort
+    let l:conn = s:FindConnection('id', a:conn_id)
     let l:notified = 0
 
-    if l:d.document_open
-        let l:new_tick = getbufvar(l:d.buffer, 'changedtick')
+    if !empty(l:conn) && has_key(l:conn.open_documents, a:buffer)
+        let l:new_tick = getbufvar(a:buffer, 'changedtick')
 
-        if l:d.conn.open_documents[l:d.buffer] < l:new_tick
-            if empty(l:d.language_id)
-                let l:message = ale#lsp#tsserver_message#Change(l:d.buffer)
+        if l:conn.open_documents[a:buffer] < l:new_tick
+            if l:conn.is_tsserver
+                let l:message = ale#lsp#tsserver_message#Change(a:buffer)
             else
-                let l:message = ale#lsp#message#DidChange(l:d.buffer)
+                let l:message = ale#lsp#message#DidChange(a:buffer)
             endif
 
-            call ale#lsp#Send(l:d.connection_id, l:message, l:d.project_root)
-            let l:d.conn.open_documents[l:d.buffer] = l:new_tick
+            call ale#lsp#Send(a:conn_id, l:message, a:project_root)
+            let l:conn.open_documents[a:buffer] = l:new_tick
             let l:notified = 1
         endif
     endif
 
     return l:notified
 endfunction
+
+" Given some LSP details that must contain at least `connection_id` and
+" `project_root` keys,
+function! ale#lsp#WaitForCapability(conn_id, project_root, capability, callback) abort
+    let l:conn = s:FindConnection('id', a:conn_id)
+    let l:project = ale#lsp#GetProject(l:conn, a:project_root)
+
+    if empty(l:project)
+        return 0
+    endif
+
+    if type(get(l:conn.capabilities, a:capability, v:null)) isnot type(0)
+        throw 'Invalid capability ' . a:capability
+    endif
+
+    if l:project.initialized
+        if l:conn.is_tsserver || l:conn.capabilities[a:capability]
+            " The project has been initialized, so call the callback now.
+            call call(a:callback, [a:conn_id, a:project_root])
+        endif
+    else
+        " Call the callback later, once we have the information we need.
+        call add(l:project.capabilities_queue, [a:capability, a:callback])
+    endif
+endfunction
diff --git a/autoload/ale/lsp_linter.vim b/autoload/ale/lsp_linter.vim
index 6dc78e4c..87aee759 100644
--- a/autoload/ale/lsp_linter.vim
+++ b/autoload/ale/lsp_linter.vim
@@ -126,10 +126,9 @@ function! ale#lsp_linter#GetOptions(buffer, linter) abort
     return l:initialization_options
 endfunction
 
-" Given a buffer, an LSP linter, and a callback to register for handling
-" messages, start up an LSP linter and get ready to receive errors or
-" completions.
-function! ale#lsp_linter#StartLSP(buffer, linter, callback) abort
+" Given a buffer, an LSP linter, start up an LSP linter and get ready to
+" receive messages for the document.
+function! ale#lsp_linter#StartLSP(buffer, linter) abort
     let l:command = ''
     let l:address = ''
     let l:root = ale#util#GetFunction(a:linter.project_root_callback)(a:buffer)
@@ -140,16 +139,11 @@ function! ale#lsp_linter#StartLSP(buffer, linter, callback) abort
         return {}
     endif
 
-    let l:initialization_options = ale#lsp_linter#GetOptions(a:buffer, a:linter)
+    let l:init_options = ale#lsp_linter#GetOptions(a:buffer, a:linter)
 
     if a:linter.lsp is# 'socket'
         let l:address = ale#linter#GetAddress(a:buffer, a:linter)
-        let l:conn_id = ale#lsp#ConnectToAddress(
-        \   l:address,
-        \   l:root,
-        \   a:callback,
-        \   l:initialization_options,
-        \)
+        let l:conn_id = ale#lsp#ConnectToAddress(l:address, l:init_options)
     else
         let l:executable = ale#linter#GetExecutable(a:buffer, a:linter)
 
@@ -164,14 +158,10 @@ function! ale#lsp_linter#StartLSP(buffer, linter, callback) abort
         let l:conn_id = ale#lsp#StartProgram(
         \   l:executable,
         \   l:command,
-        \   l:root,
-        \   a:callback,
-        \   l:initialization_options,
+        \   l:init_options,
         \)
     endif
 
-    let l:language_id = ale#util#GetFunction(a:linter.language_callback)(a:buffer)
-
     if empty(l:conn_id)
         if g:ale_history_enabled && !empty(l:command)
             call ale#history#Add(a:buffer, 'failed', l:conn_id, l:command)
@@ -180,6 +170,16 @@ function! ale#lsp_linter#StartLSP(buffer, linter, callback) abort
         return {}
     endif
 
+    " tsserver behaves differently, so tell the LSP API that it is tsserver.
+    if a:linter.lsp is# 'tsserver'
+        call ale#lsp#MarkConnectionAsTsserver(l:conn_id)
+    endif
+
+    " Register the project now the connection is ready.
+    call ale#lsp#RegisterProject(l:conn_id, l:root)
+
+    let l:language_id = ale#util#GetFunction(a:linter.language_callback)(a:buffer)
+
     let l:details = {
     \   'buffer': a:buffer,
     \   'connection_id': l:conn_id,
@@ -188,7 +188,7 @@ function! ale#lsp_linter#StartLSP(buffer, linter, callback) abort
     \   'language_id': l:language_id,
     \}
 
-    if ale#lsp#OpenDocument(l:details)
+    if ale#lsp#OpenDocument(l:conn_id, l:root, a:buffer, l:language_id)
         if g:ale_history_enabled && !empty(l:command)
             call ale#history#Add(a:buffer, 'started', l:conn_id, l:command)
         endif
@@ -196,7 +196,7 @@ function! ale#lsp_linter#StartLSP(buffer, linter, callback) abort
 
     " The change message needs to be sent for tsserver before doing anything.
     if a:linter.lsp is# 'tsserver'
-        call ale#lsp#NotifyForChanges(l:details)
+        call ale#lsp#NotifyForChanges(l:conn_id, l:root, a:buffer)
     endif
 
     return l:details
@@ -204,11 +204,7 @@ endfunction
 
 function! ale#lsp_linter#CheckWithLSP(buffer, linter) abort
     let l:info = g:ale_buffer_info[a:buffer]
-    let l:lsp_details = ale#lsp_linter#StartLSP(
-    \   a:buffer,
-    \   a:linter,
-    \   function('ale#lsp_linter#HandleLSPResponse'),
-    \)
+    let l:lsp_details = ale#lsp_linter#StartLSP(a:buffer, a:linter)
 
     if empty(l:lsp_details)
         return 0
@@ -217,25 +213,25 @@ function! ale#lsp_linter#CheckWithLSP(buffer, linter) abort
     let l:id = l:lsp_details.connection_id
     let l:root = l:lsp_details.project_root
 
+    " Register a callback now for handling errors now.
+    let l:Callback = function('ale#lsp_linter#HandleLSPResponse')
+    call ale#lsp#RegisterCallback(l:id, l:Callback)
+
     " Remember the linter this connection is for.
     let s:lsp_linter_map[l:id] = a:linter.name
 
     if a:linter.lsp is# 'tsserver'
         let l:message = ale#lsp#tsserver_message#Geterr(a:buffer)
-        let l:request_id = ale#lsp#Send(l:id, l:message, l:root)
-
-        let l:notified = l:request_id != 0
+        let l:notified = ale#lsp#Send(l:id, l:message, l:root) != 0
     else
-        let l:notified = ale#lsp#NotifyForChanges(l:lsp_details)
+        let l:notified = ale#lsp#NotifyForChanges(l:id, l:root, a:buffer)
     endif
 
     " If this was a file save event, also notify the server of that.
     if a:linter.lsp isnot# 'tsserver'
     \&& getbufvar(a:buffer, 'ale_save_event_fired', 0)
         let l:save_message = ale#lsp#message#DidSave(a:buffer)
-        let l:request_id = ale#lsp#Send(l:id, l:save_message, l:root)
-
-        let l:notified = l:request_id != 0
+        let l:notified = ale#lsp#Send(l:id, l:save_message, l:root) != 0
     endif
 
     if l:notified
diff --git a/autoload/ale/references.vim b/autoload/ale/references.vim
index 89df69eb..3a710b7b 100644
--- a/autoload/ale/references.vim
+++ b/autoload/ale/references.vim
@@ -68,37 +68,46 @@ function! s:FindReferences(linter) abort
     let l:buffer = bufnr('')
     let [l:line, l:column] = getcurpos()[1:2]
 
-    let l:Callback = a:linter.lsp is# 'tsserver'
-    \   ? function('ale#references#HandleTSServerResponse')
-    \   : function('ale#references#HandleLSPResponse')
+    if a:linter.lsp isnot# 'tsserver'
+        let l:column = min([l:column, len(getline(l:line))])
+    endif
 
-    let l:lsp_details = ale#lsp_linter#StartLSP(l:buffer, a:linter, l:Callback)
+    let l:lsp_details = ale#lsp_linter#StartLSP(l:buffer, a:linter)
 
     if empty(l:lsp_details)
         return 0
     endif
 
     let l:id = l:lsp_details.connection_id
+    let l:root = l:lsp_details.project_root
 
-    if a:linter.lsp is# 'tsserver'
-        let l:message = ale#lsp#tsserver_message#References(
-        \   l:buffer,
-        \   l:line,
-        \   l:column
-        \)
-    else
-        " Send a message saying the buffer has changed first, or the
-        " references position probably won't make sense.
-        call ale#lsp#NotifyForChanges(l:lsp_details)
+    function! OnReady(...) abort closure
+        let l:Callback = a:linter.lsp is# 'tsserver'
+        \   ? function('ale#references#HandleTSServerResponse')
+        \   : function('ale#references#HandleLSPResponse')
 
-        let l:column = min([l:column, len(getline(l:line))])
+        call ale#lsp#RegisterCallback(l:id, l:Callback)
 
-        let l:message = ale#lsp#message#References(l:buffer, l:line, l:column)
-    endif
+        if a:linter.lsp is# 'tsserver'
+            let l:message = ale#lsp#tsserver_message#References(
+            \   l:buffer,
+            \   l:line,
+            \   l:column
+            \)
+        else
+            " Send a message saying the buffer has changed first, or the
+            " references position probably won't make sense.
+            call ale#lsp#NotifyForChanges(l:id, l:root, l:buffer)
+
+            let l:message = ale#lsp#message#References(l:buffer, l:line, l:column)
+        endif
+
+        let l:request_id = ale#lsp#Send(l:id, l:message, l:lsp_details.project_root)
 
-    let l:request_id = ale#lsp#Send(l:id, l:message, l:lsp_details.project_root)
+        let s:references_map[l:request_id] = {}
+    endfunction
 
-    let s:references_map[l:request_id] = {}
+    call ale#lsp#WaitForCapability(l:id, l:root, 'references', function('OnReady'))
 endfunction
 
 function! ale#references#Find() abort
diff --git a/autoload/ale/test.vim b/autoload/ale/test.vim
index bea10c53..083b546f 100644
--- a/autoload/ale/test.vim
+++ b/autoload/ale/test.vim
@@ -52,3 +52,26 @@ function! ale#test#SetFilename(path) abort
 
     silent! noautocmd execute 'file ' . fnameescape(ale#path#Simplify(l:full_path))
 endfunction
+
+function! s:RemoveModule(results) abort
+    for l:item in a:results
+      if has_key(l:item, 'module')
+        call remove(l:item, 'module')
+      endif
+    endfor
+endfunction
+
+" Return loclist data without the module string, only in newer Vim versions.
+function! ale#test#GetLoclistWithoutModule() abort
+    let l:results = getloclist(0)
+    call s:RemoveModule(l:results)
+
+    return l:results
+endfunction
+
+function! ale#test#GetQflistWithoutModule() abort
+    let l:results = getqflist()
+    call s:RemoveModule(l:results)
+
+    return l:results
+endfunction
diff --git a/autoload/ale/toggle.vim b/autoload/ale/toggle.vim
index 6b1affc4..da108782 100644
--- a/autoload/ale/toggle.vim
+++ b/autoload/ale/toggle.vim
@@ -43,7 +43,7 @@ function! ale#toggle#Toggle() abort
         call s:CleanupEveryBuffer()
         call s:DisablePostamble()
 
-        if has('balloon_eval')
+        if exists('*ale#balloon#Disable')
             call ale#balloon#Disable()
         endif
     endif
diff --git a/doc/ale-c.txt b/doc/ale-c.txt
index c41f3bc8..acff722c 100644
--- a/doc/ale-c.txt
+++ b/doc/ale-c.txt
@@ -64,6 +64,25 @@ g:ale_c_clang_options                                   *g:ale_c_clang_options*
 
 
 ===============================================================================
+clangd                                                           *ale-c-clangd*
+
+g:ale_c_clangd_executable                           *g:ale_c_clangd_executable*
+                                                    *b:ale_c_clangd_executable*
+  Type: |String|
+  Default: `'clangd'`
+
+  This variable can be changed to use a different executable for clangd.
+
+
+g:ale_c_clangd_options                                 *g:ale_c_clangd_options*
+                                                       *b:ale_c_clangd_options*
+  Type: |String|
+  Default: `''`
+
+  This variable can be changed to modify flags given to clangd.
+
+
+===============================================================================
 clang-format                                                *ale-c-clangformat*
 
 g:ale_c_clangformat_executable                 *g:ale_c_clangformat_executable*
diff --git a/doc/ale-development.txt b/doc/ale-development.txt
index 5688c1cc..8a4c1d7d 100644
--- a/doc/ale-development.txt
+++ b/doc/ale-development.txt
@@ -115,6 +115,9 @@ these are reported with ALE's `custom-linting-rules` script. See
 * Don't use the `tempname()` function. It doesn't work when `$TMPDIR` isn't
   set. Use `ale#util#Tempname()` instead, which temporarily sets `$TMPDIR`
   appropriately where needed.
+* Use `snake_case` names for linter names, so they can be used as part of
+  variable names. You can define `aliases` for linters, for other names people
+  might try to configure linters with.
 
 Apply the following guidelines when writing Vader test files.
 
@@ -145,9 +148,10 @@ ALE is tested with a suite of tests executed in Travis CI and AppVeyor. ALE
 runs tests with the following versions of Vim in the following environments.
 
 1. Vim 8.0.0027 on Linux via Travis CI.
-2. NeoVim 0.2.0 on Linux via Travis CI.
-3. NeoVim 0.3.0 on Linux via Travis CI.
-4. Vim 8 (stable builds) on Windows via AppVeyor.
+2. Vim 8.1.0204 on Linux via Travis CI.
+3. NeoVim 0.2.0 on Linux via Travis CI.
+4. NeoVim 0.3.0 on Linux via Travis CI.
+5. Vim 8 (stable builds) on Windows via AppVeyor.
 
 If you are developing ALE code on Linux, Mac OSX, or BSD, you can run ALEs
 tests by installing Docker and running the `run-tests` script. Follow the
diff --git a/doc/ale-fortran.txt b/doc/ale-fortran.txt
index ed6bc724..c9b7e8e2 100644
--- a/doc/ale-fortran.txt
+++ b/doc/ale-fortran.txt
@@ -33,4 +33,23 @@ g:ale_fortran_gcc_use_free_form               *g:ale_fortran_gcc_use_free_form*
 
 
 ===============================================================================
+language_server                                    *ale-fortran-language-server*
+
+g:ale_fortran_language_server_executable  *g:ale_fortran_language_server_executable*
+                                         *b:ale_fortran_language_server_executable*
+  Type: |String|
+  Default: `'fortls'`
+
+  This variable can be changed to modify the executable used for the Fortran
+  Language Server.
+
+g:ale_fortran_language_server_use_global  *g:ale_fortran_language_server_use_global*
+                                         *b:ale_fortran_language_server_use_global*
+  Type: |Number|
+  Default: `get(g:, 'ale_use_global_executables', 0)`
+
+  See |ale-integrations-local-executables|
+
+
+===============================================================================
   vim:tw=78:ts=2:sts=2:sw=2:ft=help:norl:
diff --git a/doc/ale-haskell.txt b/doc/ale-haskell.txt
index 09ecd92d..15d3ce48 100644
--- a/doc/ale-haskell.txt
+++ b/doc/ale-haskell.txt
@@ -23,6 +23,17 @@ g:ale_haskell_ghc_options                           *g:ale_haskell_ghc_options*
   This variable can be changed to modify flags given to ghc.
 
 ===============================================================================
+cabal-ghc                                               *ale-haskell-cabal-ghc*
+
+g:ale_haskell_cabal_ghc_options               *g:ale_haskell_cabal_ghc_options*
+                                              *b:ale_haskell_cabal_ghc_options*
+  Type: |String|
+  Default: `'-fno-code -v0'`
+
+  This variable can be changed to modify flags given to ghc through cabal
+  exec.
+
+===============================================================================
 hdevtools                                               *ale-haskell-hdevtools*
 
 g:ale_haskell_hdevtools_executable         *g:ale_haskell_hdevtools_executable*
diff --git a/doc/ale.txt b/doc/ale.txt
index 2b25091e..8182c27a 100644
--- a/doc/ale.txt
+++ b/doc/ale.txt
@@ -26,6 +26,7 @@ CONTENTS                                                         *ale-contents*
       gawk................................|ale-awk-gawk|
     c.....................................|ale-c-options|
       clang...............................|ale-c-clang|
+      clangd..............................|ale-c-clangd|
       clang-format........................|ale-c-clangformat|
       clangtidy...........................|ale-c-clangtidy|
       cppcheck............................|ale-c-cppcheck|
@@ -76,6 +77,7 @@ CONTENTS                                                         *ale-contents*
     fish..................................|ale-fish-options|
     fortran...............................|ale-fortran-options|
       gcc.................................|ale-fortran-gcc|
+      language_server.....................|ale-fortran-language-server|
     fountain..............................|ale-fountain-options|
     fusionscript..........................|ale-fuse-options|
       fusion-lint.........................|ale-fuse-fusionlint|
@@ -98,6 +100,7 @@ CONTENTS                                                         *ale-contents*
     haskell...............................|ale-haskell-options|
       brittany............................|ale-haskell-brittany|
       ghc.................................|ale-haskell-ghc|
+      cabal-ghc...........................|ale-haskell-cabal-ghc|
       hdevtools...........................|ale-haskell-hdevtools|
       hfmt................................|ale-haskell-hfmt|
       stack-build.........................|ale-haskell-stack-build|
@@ -333,7 +336,7 @@ Notes:
 * Awk: `gawk`
 * Bash: `language-server`, `shell` (-n flag), `shellcheck`, `shfmt`
 * Bourne Shell: `shell` (-n flag), `shellcheck`, `shfmt`
-* C: `cppcheck`, `cpplint`!!, `clang`, `clangtidy`!!, `clang-format`, `flawfinder`, `gcc`
+* C: `cppcheck`, `cpplint`!!, `clang`, `clangd`, `clangtidy`!!, `clang-format`, `flawfinder`, `gcc`
 * C++ (filetype cpp): `clang`, `clangcheck`!!, `clangtidy`!!, `clang-format`, `cppcheck`, `cpplint`!!, `cquery`, `flawfinder`, `gcc`
 * CUDA: `nvcc`!!
 * C#: `mcs`, `mcsc`!!
@@ -355,7 +358,7 @@ Notes:
 * Erb: `erb`, `erubi`, `erubis`
 * Erlang: `erlc`, `SyntaxErl`
 * Fish: `fish` (-n flag)
-* Fortran: `gcc`
+* Fortran: `gcc`, `language_server`
 * Fountain: `proselint`
 * FusionScript: `fusion-lint`
 * Git Commit Messages: `gitlint`
@@ -364,7 +367,7 @@ Notes:
 * GraphQL: `eslint`, `gqlint`, `prettier`
 * Haml: `haml-lint`
 * Handlebars: `ember-template-lint`
-* Haskell: `brittany`, `ghc`, `stack-ghc`, `stack-build`!!, `ghc-mod`, `stack-ghc-mod`, `hlint`, `hdevtools`, `hfmt`
+* Haskell: `brittany`, `ghc`, `cabal-ghc`, `stack-ghc`, `stack-build`!!, `ghc-mod`, `stack-ghc-mod`, `hlint`, `hdevtools`, `hfmt`
 * HTML: `alex`!!, `HTMLHint`, `proselint`, `tidy`, `write-good`
 * Idris: `idris`
 * Java: `checkstyle`, `javac`, `google-java-format`, `PMD`
@@ -1413,8 +1416,7 @@ g:ale_set_balloons                                         *g:ale_set_balloons*
                                                            *b:ale_set_balloons*
 
   Type: |Number|
-  Default: `(has('balloon_eval') && has('gui_running'))`
-           `|| (has('balloon_eval_term') && !has('gui_running'))`
+  Default: `has('balloon_eval') && has('gui_running')`
 
   When this option is set to `1`, balloon messages will be displayed for
   problems or hover information if available.
@@ -1424,6 +1426,12 @@ g:ale_set_balloons                                         *g:ale_set_balloons*
   supporting "Hover" information, per |ale-hover|, then brief information
   about the symbol under the cursor will be displayed in a balloon.
 
+  Balloons can be enabled for terminal versions of Vim that support balloons,
+  but some versions of Vim will produce strange mouse behavior when balloons
+  are enabled. To configure balloons for your terminal, you should first
+  configure your |ttymouse| setting, and then consider setting
+  `g:ale_set_balloons` to `1` before ALE is loaded.
+
   `b:ale_set_balloons` can be set to `0` to disable balloons for a buffer.
   Balloons cannot be enabled for a specific buffer when not initially enabled
   globally.
diff --git a/plugin/ale.vim b/plugin/ale.vim
index ad2639bb..f0f90b6b 100644
--- a/plugin/ale.vim
+++ b/plugin/ale.vim
@@ -110,10 +110,7 @@ let g:ale_set_highlights = get(g:, 'ale_set_highlights', has('syntax'))
 let g:ale_echo_cursor = get(g:, 'ale_echo_cursor', 1)
 
 " This flag can be set to 0 to disable balloon support.
-let g:ale_set_balloons = get(g:, 'ale_set_balloons',
-\   (has('balloon_eval') && has('gui_running'))
-\   || (has('balloon_eval_term') && !has('gui_running'))
-\)
+let g:ale_set_balloons = get(g:, 'ale_set_balloons', has('balloon_eval') && has('gui_running'))
 
 " This flag can be set to 0 to disable warnings for trailing whitespace
 let g:ale_warn_about_trailing_whitespace = get(g:, 'ale_warn_about_trailing_whitespace', 1)
diff --git a/run-tests b/run-tests
index ad375693..06fa3547 100755
--- a/run-tests
+++ b/run-tests
@@ -10,7 +10,7 @@ set -u
 #
 
 image=w0rp/ale
-current_image_id=71553d0ab3e8
+current_image_id=67896c9c2c0f
 
 # Used in all test scripts for running the selected Docker image.
 DOCKER_RUN_IMAGE="$image"
@@ -22,7 +22,8 @@ verbose_flag=''
 quiet_flag=''
 run_neovim_02_tests=1
 run_neovim_03_tests=1
-run_vim_tests=1
+run_vim_80_tests=1
+run_vim_81_tests=1
 run_linters=1
 
 while [ $# -ne 0 ]; do
@@ -36,19 +37,22 @@ while [ $# -ne 0 ]; do
         shift
     ;;
     --neovim-only)
-        run_vim_tests=0
+        run_vim_80_tests=0
+        run_vim_81_tests=0
         run_linters=0
         shift
     ;;
     --neovim-02-only)
         run_neovim_03_tests=0
-        run_vim_tests=0
+        run_vim_80_tests=0
+        run_vim_81_tests=0
         run_linters=0
         shift
     ;;
     --neovim-03-only)
         run_neovim_02_tests=0
-        run_vim_tests=0
+        run_vim_80_tests=0
+        run_vim_81_tests=0
         run_linters=0
         shift
     ;;
@@ -58,8 +62,23 @@ while [ $# -ne 0 ]; do
         run_linters=0
         shift
     ;;
+    --vim-80-only)
+        run_neovim_02_tests=0
+        run_neovim_03_tests=0
+        run_vim_81_tests=0
+        run_linters=0
+        shift
+    ;;
+    --vim-81-only)
+        run_neovim_02_tests=0
+        run_neovim_03_tests=0
+        run_vim_80_tests=0
+        run_linters=0
+        shift
+    ;;
     --linters-only)
-        run_vim_tests=0
+        run_vim_80_tests=0
+        run_vim_81_tests=0
         run_neovim_02_tests=0
         run_neovim_03_tests=0
         shift
@@ -76,7 +95,9 @@ while [ $# -ne 0 ]; do
         echo '  --neovim-only     Run tests only for NeoVim 0.2 and 0.3'
         echo '  --neovim-02-only  Run tests only for NeoVim 0.2'
         echo '  --neovim-03-only  Run tests only for NeoVim 0.3'
-        echo '  --vim-only        Run tests only for Vim'
+        echo '  --vim-only        Run tests only for Vim 8.0 and 8.1'
+        echo '  --vim-80-only     Run tests only for Vim 8.0'
+        echo '  --vim-81-only     Run tests only for Vim 8.1'
         echo '  --linters-only    Run only Vint and custom checks'
         echo '  --help            Show this help text'
         echo '  --                Stop parsing options after this'
@@ -120,7 +141,8 @@ file_number=0
 pid_list=''
 
 for vim in $(docker run --rm "$DOCKER_RUN_IMAGE" ls /vim-build/bin | grep '^neovim\|^vim' ); do
-    if ( [[ $vim =~ ^vim ]] && ((run_vim_tests)) ) \
+    if ( [[ $vim =~ ^vim-v8.0 ]] && ((run_vim_80_tests)) ) \
+    || ( [[ $vim =~ ^vim-v8.1 ]] && ((run_vim_81_tests)) ) \
     || ( [[ $vim =~ ^neovim-v0.2 ]] && ((run_neovim_02_tests)) ) \
     || ( [[ $vim =~ ^neovim-v0.3 ]] && ((run_neovim_03_tests)) ); then
         echo "Starting Vim: $vim..."
diff --git a/test/command_callback/clangd_paths/compile_commands.json b/test/command_callback/clangd_paths/compile_commands.json
new file mode 100644
index 00000000..e69de29b
--- /dev/null
+++ b/test/command_callback/clangd_paths/compile_commands.json
diff --git a/test/command_callback/fortran-fortls-project/.fortls b/test/command_callback/fortran-fortls-project/.fortls
new file mode 100644
index 00000000..2c63c085
--- /dev/null
+++ b/test/command_callback/fortran-fortls-project/.fortls
@@ -0,0 +1,2 @@
+{
+}
diff --git a/test/command_callback/test_c_clangd_command_callbacks.vader b/test/command_callback/test_c_clangd_command_callbacks.vader
new file mode 100644
index 00000000..c8c10b67
--- /dev/null
+++ b/test/command_callback/test_c_clangd_command_callbacks.vader
@@ -0,0 +1,32 @@
+Before:
+  call ale#assert#SetUpLinterTest('c', 'clangd')
+
+  Save &filetype
+  let &filetype = 'c'
+
+After:
+  call ale#assert#TearDownLinterTest()
+
+Execute(The language string should be correct):
+  AssertLSPLanguage 'c'
+
+Execute(The default executable should be correct):
+  AssertLinter 'clangd', ale#Escape('clangd')
+
+Execute(The project root should be detected correctly):
+  AssertLSPProject ''
+
+  call ale#test#SetFilename('clangd_paths/dummy.c')
+
+  AssertLSPProject ale#path#Simplify(g:dir . '/clangd_paths')
+
+Execute(The executable should be configurable):
+  let g:ale_c_clangd_executable = 'foobar'
+
+  AssertLinter 'foobar', ale#Escape('foobar')
+
+Execute(The options should be configurable):
+  let b:ale_c_clangd_options = '-compile-commands-dir=foo'
+
+  AssertLinter 'clangd', ale#Escape('clangd') . ' ' . b:ale_c_clangd_options
+
diff --git a/test/command_callback/test_fortran_fortls_callback.vader b/test/command_callback/test_fortran_fortls_callback.vader
new file mode 100644
index 00000000..3be7ff4f
--- /dev/null
+++ b/test/command_callback/test_fortran_fortls_callback.vader
@@ -0,0 +1,18 @@
+Before:
+  call ale#assert#SetUpLinterTest('fortran', 'language_server')
+
+After:
+  call ale#assert#TearDownLinterTest()
+
+Execute(The default executable path should be correct):
+  AssertLinter 'fortls', ale#Escape('fortls')
+
+Execute(The project root should be detected correctly):
+  AssertLSPProject ''
+
+  call ale#test#SetFilename('fortran-fortls-project/test.F90')
+
+  AssertLSPProject ale#path#Simplify(g:dir . '/fortran-fortls-project')
+
+Execute(The language should be correct):
+  AssertLSPLanguage 'fortran'
diff --git a/test/command_callback/test_haskell_cabal_ghc_command_callbacks.vader b/test/command_callback/test_haskell_cabal_ghc_command_callbacks.vader
new file mode 100644
index 00000000..650aefa3
--- /dev/null
+++ b/test/command_callback/test_haskell_cabal_ghc_command_callbacks.vader
@@ -0,0 +1,23 @@
+Before:
+  Save g:ale_haskell_cabal_ghc_options
+
+  unlet! g:ale_haskell_cabal_ghc_options
+  unlet! b:ale_haskell_cabal_ghc_options
+
+  runtime ale_linters/haskell/cabal_ghc.vim
+
+After:
+  Restore
+  unlet! b:ale_haskell_cabal_ghc_options
+  call ale#linter#Reset()
+
+Execute(The options should be used in the command):
+  AssertEqual
+  \ 'cabal exec -- ghc -fno-code -v0 %t',
+  \ ale_linters#haskell#cabal_ghc#GetCommand(bufnr(''))
+
+  let b:ale_haskell_cabal_ghc_options = 'foobar'
+
+  AssertEqual
+  \ 'cabal exec -- ghc foobar %t',
+  \ ale_linters#haskell#cabal_ghc#GetCommand(bufnr(''))
diff --git a/test/completion/test_completion_events.vader b/test/completion/test_completion_events.vader
index f8cf268c..f3e05950 100644
--- a/test/completion/test_completion_events.vader
+++ b/test/completion/test_completion_events.vader
@@ -32,8 +32,16 @@ Before:
     endfunction
 
     let g:ale_completion_delay = 0
-    call ale#completion#Queue()
-    sleep 1m
+
+    " Run this check a few times, as it can fail randomly.
+    for g:i in range(has('nvim-0.3') || has('win32') ? 5 : 1)
+      call ale#completion#Queue()
+      sleep 1m
+
+      if g:get_completions_called is a:expect_success
+        break
+      endif
+    endfor
 
     AssertEqual a:expect_success, g:get_completions_called
   endfunction
diff --git a/test/completion/test_lsp_completion_messages.vader b/test/completion/test_lsp_completion_messages.vader
index 00a174dc..ed0f358b 100644
--- a/test/completion/test_lsp_completion_messages.vader
+++ b/test/completion/test_lsp_completion_messages.vader
@@ -13,11 +13,11 @@ Before:
   runtime autoload/ale/lsp.vim
 
   let g:message_list = []
+  let g:capability_checked = ''
   let g:Callback = ''
+  let g:wait_callback_list = []
 
-  function! ale#lsp_linter#StartLSP(buffer, linter, callback) abort
-    let g:Callback = a:callback
-
+  function! ale#lsp_linter#StartLSP(buffer, linter) abort
     let l:conn = ale#lsp#NewConnection({})
     let l:conn.id = 347
     let l:conn.open_documents = {a:buffer : -1}
@@ -35,15 +35,28 @@ Before:
     return 'i'
   endfunction
 
+  function! ale#lsp#WaitForCapability(conn_id, project_root, capability, callback) abort
+    let g:capability_checked = a:capability
+    call add(g:wait_callback_list, a:callback)
+  endfunction
+
+  function! ale#lsp#RegisterCallback(conn_id, callback) abort
+    let g:Callback = a:callback
+  endfunction
+
   " Replace the Send function for LSP, so we can monitor calls to it.
   function! ale#lsp#Send(conn_id, message, ...) abort
     call add(g:message_list, a:message)
+
+    return 1
   endfunction
 
 After:
   Restore
 
   unlet! g:message_list
+  unlet! g:capability_checked
+  unlet! g:wait_callback_list
   unlet! g:Callback
   unlet! b:ale_old_omnifunc
   unlet! b:ale_old_completopt
@@ -84,6 +97,13 @@ Execute(The right message should be sent for the initial tsserver request):
 
   call ale#completion#GetCompletions()
 
+  " We shouldn't register the callback yet.
+  AssertEqual '''''', string(g:Callback)
+
+  AssertEqual 1, len(g:wait_callback_list)
+  AssertEqual 'completion', g:capability_checked
+  call map(g:wait_callback_list, 'v:val([347, ''/foo/bar''])')
+
   " We should send the right callback.
   AssertEqual
   \ 'function(''ale#completion#HandleTSServerResponse'')',
@@ -96,9 +116,9 @@ Execute(The right message should be sent for the initial tsserver request):
   AssertEqual
   \ {
   \   'line_length': 3,
-  \   'conn_id': 0,
+  \   'conn_id': 347,
   \   'column': 3,
-  \   'request_id': 0,
+  \   'request_id': 1,
   \   'line': 1,
   \   'prefix': 'fo',
   \ },
@@ -164,6 +184,13 @@ Execute(The right message should be sent for the initial LSP request):
 
   call ale#completion#GetCompletions()
 
+  " We shouldn't register the callback yet.
+  AssertEqual '''''', string(g:Callback)
+
+  AssertEqual 1, len(g:wait_callback_list)
+  AssertEqual 'completion', g:capability_checked
+  call map(g:wait_callback_list, 'v:val([347, ''/foo/bar''])')
+
   " We should send the right callback.
   AssertEqual
   \ 'function(''ale#completion#HandleLSPResponse'')',
@@ -192,10 +219,58 @@ Execute(The right message should be sent for the initial LSP request):
   AssertEqual
   \ {
   \   'line_length': 3,
-  \   'conn_id': 0,
+  \   'conn_id': 347,
   \   'column': 3,
-  \   'request_id': 0,
+  \   'request_id': 1,
   \   'line': 1,
   \   'prefix': 'fo',
+  \   'completion_filter': 'ale#completion#python#CompletionItemFilter',
   \ },
   \ get(b:, 'ale_completion_info', {})
+
+Execute(Two completion requests shouldn't be sent in a row):
+  call ale#linter#PreventLoading('python')
+  call ale#linter#Define('python', {
+  \   'name': 'foo',
+  \   'lsp': 'stdio',
+  \   'executable': 'foo',
+  \   'command': 'foo',
+  \   'project_root_callback': {-> '/foo/bar'},
+  \})
+  call ale#linter#Define('python', {
+  \   'name': 'bar',
+  \   'lsp': 'stdio',
+  \   'executable': 'foo',
+  \   'command': 'foo',
+  \   'project_root_callback': {-> '/foo/bar'},
+  \})
+  let b:ale_linters = ['foo', 'bar']
+
+  " The cursor position needs to match what was saved before.
+  call setpos('.', [bufnr(''), 1, 5, 0])
+
+  call ale#completion#GetCompletions()
+
+  " We shouldn't register the callback yet.
+  AssertEqual '''''', string(g:Callback)
+
+  AssertEqual 2, len(g:wait_callback_list)
+  AssertEqual 'completion', g:capability_checked
+  call map(g:wait_callback_list, 'v:val([347, ''/foo/bar''])')
+
+  " We should only send one completion message for two LSP servers.
+  AssertEqual
+  \ [
+  \   [1, 'textDocument/didChange', {
+  \     'textDocument': {
+  \         'uri': ale#path#ToURI(expand('%:p')),
+  \         'version': g:ale_lsp_next_version_id - 1,
+  \     },
+  \     'contentChanges': [{'text': join(getline(1, '$'), "\n") . "\n"}]
+  \   }],
+  \   [0, 'textDocument/completion', {
+  \   'textDocument': {'uri': ale#path#ToURI(expand('%:p'))},
+  \   'position': {'line': 0, 'character': 3},
+  \   }],
+  \ ],
+  \ g:message_list
diff --git a/test/completion/test_lsp_completion_parsing.vader b/test/completion/test_lsp_completion_parsing.vader
index 736353e3..d5a45b54 100644
--- a/test/completion/test_lsp_completion_parsing.vader
+++ b/test/completion/test_lsp_completion_parsing.vader
@@ -430,10 +430,10 @@ Execute(Should handle Python completion results correctly):
   \   }
   \ })
 
-Execute(Should handle missing detail keys):
+Execute(Should handle missing keys):
   AssertEqual
   \ [
-  \   {'word': 'x', 'menu': '', 'info': 'y', 'kind': 'f', 'icase': 1},
+  \   {'word': 'x', 'menu': '', 'info': '', 'kind': 'v', 'icase': 1},
   \ ],
   \ ale#completion#ParseLSPCompletions({
   \   'jsonrpc': '2.0',
@@ -443,8 +443,6 @@ Execute(Should handle missing detail keys):
   \     'items': [
   \       {
   \         'label': 'x',
-  \         'kind': 3,
-  \         'documentation': 'y',
   \       },
   \     ]
   \   }
diff --git a/test/fix/test_ale_fix.vader b/test/fix/test_ale_fix.vader
index 80eda4a0..67b8b212 100644
--- a/test/fix/test_ale_fix.vader
+++ b/test/fix/test_ale_fix.vader
@@ -458,7 +458,7 @@ Execute(ALEFix should save files on the save event):
     \   'nr': -1,
     \   'pattern': '',
     \   'valid': 1,
-    \}], getloclist(0)
+    \}], ale#test#GetLoclistWithoutModule()
   endif
 
 Expect(The buffer should be modified):
@@ -497,7 +497,7 @@ Execute(ALEFix should still lint with no linters to be applied):
     \   'nr': -1,
     \   'pattern': '',
     \   'valid': 1,
-    \}], getloclist(0)
+    \}], ale#test#GetLoclistWithoutModule()
   endif
 
 Expect(The buffer should be the same):
@@ -531,7 +531,7 @@ Execute(ALEFix should still lint when nothing was fixed on save):
     \   'nr': -1,
     \   'pattern': '',
     \   'valid': 1,
-    \}], getloclist(0)
+    \}], ale#test#GetLoclistWithoutModule()
   endif
 
 Expect(The buffer should be the same):
@@ -552,8 +552,6 @@ Execute(ale#fix#InitBufferData() should set up the correct data):
   AssertEqual {
   \ bufnr(''): {
   \   'temporary_directory_list': [],
-  \   'vars': b:,
-  \   'filename': ale#path#Simplify(getcwd() . '/fix_test_file'),
   \   'done': 0,
   \   'lines_before': ['a', 'b', 'c'],
   \   'should_save': 1,
diff --git a/test/lsp/test_did_save_event.vader b/test/lsp/test_did_save_event.vader
index b696ee4b..428135fb 100644
--- a/test/lsp/test_did_save_event.vader
+++ b/test/lsp/test_did_save_event.vader
@@ -14,7 +14,6 @@ Before:
   let g:ale_lsp_next_message_id = 1
   let g:ale_run_synchronously = 1
   let g:message_list = []
-  let g:Callback = ''
 
   function! LanguageCallback() abort
     return 'foobar'
@@ -34,9 +33,7 @@ Before:
   \ })
   let g:ale_linters = {'foobar': ['dummy_linter']}
 
-  function! ale#lsp_linter#StartLSP(buffer, linter, callback) abort
-    let g:Callback = a:callback
-
+  function! ale#lsp_linter#StartLSP(buffer, linter) abort
     let l:conn = ale#lsp#NewConnection({})
     let l:conn.id = 347
     let l:conn.open_documents = {a:buffer : -1}
@@ -59,7 +56,6 @@ After:
 
   unlet! b:ale_enabled
   unlet! b:ale_linters
-  unlet! g:Callback
   unlet! g:message_list
 
   delfunction LanguageCallback
diff --git a/test/lsp/test_lsp_command_formatting.vader b/test/lsp/test_lsp_command_formatting.vader
index f436397f..9d2c84ee 100644
--- a/test/lsp/test_lsp_command_formatting.vader
+++ b/test/lsp/test_lsp_command_formatting.vader
@@ -23,15 +23,14 @@ Execute(Command formatting should be applied correctly for LSP linters):
   \   'executable': has('win32') ? 'cmd': 'true',
   \   'command': '%e --foo',
   \ },
-  \ {->0}
   \)
 
   if has('win32')
     AssertEqual
-    \ ['cmd', 'cmd /s/c "cmd --foo"', '/foo/bar'],
-    \ g:args[:2]
+    \ ['cmd', 'cmd /s/c "cmd --foo"', {}],
+    \ g:args
   else
     AssertEqual
-    \ ['true', [&shell, '-c', '''true'' --foo'], '/foo/bar'],
-    \ g:args[:2]
+    \ ['true', [&shell, '-c', '''true'' --foo'], {}],
+    \ g:args
   endif
diff --git a/test/lsp/test_lsp_connections.vader b/test/lsp/test_lsp_connections.vader
index 8651d801..ae64eadb 100644
--- a/test/lsp/test_lsp_connections.vader
+++ b/test/lsp/test_lsp_connections.vader
@@ -2,6 +2,10 @@ Before:
   let g:ale_lsp_next_message_id = 1
 
 After:
+  if exists('b:conn') && has_key(b:conn, 'id')
+    call ale#lsp#RemoveConnectionWithID(b:conn.id)
+  endif
+
   unlet! b:data
   unlet! b:conn
 
@@ -223,17 +227,20 @@ Execute(ale#lsp#ReadMessageData() should handle a message with part of a second
   \ )
 
 Execute(Projects with regular project roots should be registered correctly):
-  let b:conn = {'projects': {}}
-
-  call ale#lsp#RegisterProject(b:conn, '/foo/bar')
+  let b:conn = ale#lsp#NewConnection({})
+  call ale#lsp#RegisterProject(b:conn.id, '/foo/bar')
 
   AssertEqual
   \ {
-  \   'projects': {
-  \     '/foo/bar': {'initialized': 0, 'message_queue': [], 'init_request_id': 0},
+  \   '/foo/bar': {
+  \     'root': '/foo/bar',
+  \     'initialized': 0,
+  \     'message_queue': [],
+  \     'capabilities_queue': [],
+  \     'init_request_id': 0,
   \   },
   \ },
-  \ b:conn
+  \ b:conn.projects
 
 Execute(Projects with regular project roots should be fetched correctly):
   let b:conn = {
@@ -247,17 +254,20 @@ Execute(Projects with regular project roots should be fetched correctly):
   \ ale#lsp#GetProject(b:conn, '/foo/bar')
 
 Execute(Projects with empty project roots should be registered correctly):
-  let b:conn = {'projects': {}}
-
-  call ale#lsp#RegisterProject(b:conn, '')
+  let b:conn = ale#lsp#NewConnection({})
+  call ale#lsp#RegisterProject(b:conn.id, '')
 
   AssertEqual
   \ {
-  \   'projects': {
-  \     '<<EMPTY>>': {'initialized': 1, 'message_queue': [], 'init_request_id': 0},
+  \   '<<EMPTY>>': {
+  \     'root': '',
+  \     'initialized': 1,
+  \     'message_queue': [],
+  \     'capabilities_queue': [],
+  \     'init_request_id': 0,
   \   },
   \ },
-  \ b:conn
+  \ b:conn.projects
 
 Execute(Projects with empty project roots should be fetched correctly):
   let b:conn = {
diff --git a/test/lsp/test_other_initialize_message_handling.vader b/test/lsp/test_other_initialize_message_handling.vader
index 3a7c7f62..45457979 100644
--- a/test/lsp/test_other_initialize_message_handling.vader
+++ b/test/lsp/test_other_initialize_message_handling.vader
@@ -3,12 +3,20 @@ Before:
   \ 'initialized': 0,
   \ 'init_request_id': 3,
   \ 'message_queue': [],
+  \ 'capabilities_queue': [],
   \}
 
   let b:conn = {
   \ 'projects': {
   \   '/foo/bar': b:project,
   \ },
+  \ 'capabilities': {
+  \   'hover': 0,
+  \   'references': 0,
+  \   'completion': 0,
+  \   'completion_trigger_characters': [],
+  \   'definition': 0,
+  \ },
   \}
 
 After:
@@ -27,6 +35,7 @@ Execute(publishDiagnostics messages with files inside project directories should
   \   'initialized': 0,
   \   'init_request_id': 3,
   \   'message_queue': [],
+  \   'capabilities_queue': [],
   \ },
   \ b:project
 
@@ -40,6 +49,7 @@ Execute(publishDiagnostics messages with files inside project directories should
   \   'initialized': 1,
   \   'init_request_id': 3,
   \   'message_queue': [],
+  \   'capabilities_queue': [],
   \ },
   \ b:project
 
@@ -53,6 +63,7 @@ Execute(Messages with no method and capabilities should initialize projects):
   \   'initialized': 1,
   \   'init_request_id': 3,
   \   'message_queue': [],
+  \   'capabilities_queue': [],
   \ },
   \ b:project
 
@@ -64,3 +75,109 @@ Execute(Other messages should not initialize projects):
   call ale#lsp#HandleOtherInitializeResponses(b:conn, {'result': {'x': {}}})
 
   AssertEqual 0, b:project.initialized
+
+Execute(Capabilities should bet set up correctly):
+  call ale#lsp#HandleOtherInitializeResponses(b:conn, {
+  \ 'jsonrpc': '2.0',
+  \ 'id': 1,
+  \ 'result': {
+  \   'capabilities': {
+  \     'renameProvider': v:true,
+  \     'executeCommandProvider': {
+  \       'commands': [],
+  \     },
+  \     'hoverProvider': v:true,
+  \     'documentSymbolProvider': v:true,
+  \     'documentRangeFormattingProvider': v:true,
+  \     'codeLensProvider': {
+  \       'resolveProvider': v:false
+  \     },
+  \     'referencesProvider': v:true,
+  \     'textDocumentSync': 2,
+  \     'documentFormattingProvider': v:true,
+  \     'codeActionProvider': v:true,
+  \     'signatureHelpProvider': {
+  \       'triggerCharacters': ['(', ','],
+  \     },
+  \     'completionProvider': {
+  \       'triggerCharacters': ['.'],
+  \       'resolveProvider': v:false
+  \     },
+  \     'definitionProvider': v:true,
+  \     'experimental': {},
+  \     'documentHighlightProvider': v:true
+  \   },
+  \ },
+  \})
+
+  AssertEqual
+  \ {
+  \   'capabilities': {
+  \     'completion_trigger_characters': ['.'],
+  \     'completion': 1,
+  \     'references': 1,
+  \     'hover': 1,
+  \     'definition': 1,
+  \   },
+  \   'message_queue': [],
+  \   'projects': {
+  \     '/foo/bar': {
+  \       'initialized': 1,
+  \       'message_queue': [],
+  \       'capabilities_queue': [],
+  \       'init_request_id': 3,
+  \     },
+  \   },
+  \ },
+  \ b:conn
+
+Execute(Disabled capabilities should be recognised correctly):
+  call ale#lsp#HandleOtherInitializeResponses(b:conn, {
+  \ 'jsonrpc': '2.0',
+  \ 'id': 1,
+  \ 'result': {
+  \   'capabilities': {
+  \     'renameProvider': v:true,
+  \     'executeCommandProvider': {
+  \       'commands': [],
+  \     },
+  \     'hoverProvider': v:false,
+  \     'documentSymbolProvider': v:true,
+  \     'documentRangeFormattingProvider': v:true,
+  \     'codeLensProvider': {
+  \       'resolveProvider': v:false
+  \     },
+  \     'referencesProvider': v:false,
+  \     'textDocumentSync': 2,
+  \     'documentFormattingProvider': v:true,
+  \     'codeActionProvider': v:true,
+  \     'signatureHelpProvider': {
+  \       'triggerCharacters': ['(', ','],
+  \     },
+  \     'definitionProvider': v:false,
+  \     'experimental': {},
+  \     'documentHighlightProvider': v:true
+  \   },
+  \ },
+  \})
+
+  AssertEqual
+  \ {
+  \   'capabilities': {
+  \     'completion_trigger_characters': [],
+  \     'completion': 0,
+  \     'references': 0,
+  \     'hover': 0,
+  \     'definition': 0,
+  \   },
+  \   'message_queue': [],
+  \   'projects': {
+  \     '/foo/bar': {
+  \       'initialized': 1,
+  \       'message_queue': [],
+  \       'capabilities_queue': [],
+  \       'init_request_id': 3,
+  \     },
+  \   },
+  \ },
+  \ b:conn
diff --git a/test/script/custom-linting-rules b/test/script/custom-linting-rules
index 51cf5680..69c4a7a1 100755
--- a/test/script/custom-linting-rules
+++ b/test/script/custom-linting-rules
@@ -52,12 +52,17 @@ directories=("$@")
 check_errors() {
     regex="$1"
     message="$2"
+    include_arg=''
+
+    if [ $# -gt 2 ]; then
+        include_arg="--include $3"
+    fi
 
     for directory in "${directories[@]}"; do
         while IFS= read -r match; do
             RETURN_CODE=1
             echo "$match $message"
-        done < <(grep -n "$regex" "$directory"/**/*.vim \
+        done < <(grep -n "$regex" $include_arg "$directory"/**/*.vim \
             | grep -v 'no-custom-checks' \
             | grep -o '^[^:]\+:[0-9]\+' \
             | sed 's:^\./::')
@@ -75,6 +80,7 @@ if (( FIX_ERRORS )); then
     done
 fi
 
+# The arguments are: regex, explanation, [filename_filter]
 check_errors \
     '^function.*) *$' \
     'Function without abort keyword (See :help except-compat)'
@@ -95,5 +101,6 @@ check_errors '==?' "Use 'is?' instead of '==?'. 0 ==? 'foobar' is true"
 check_errors '!=#' "Use 'isnot#' instead of '!=#'. 0 !=# 'foobar' is false"
 check_errors '!=?' "Use 'isnot?' instead of '!=?'. 0 !=? 'foobar' is false"
 check_errors '^ *:\?echo' "Stray echo line. Use \`execute echo\` if you want to echo something"
+check_errors $'name.:.*\'[a-z_]*[^a-z_0-9][a-z_0-9]*\',$' 'Use snake_case names for linters' '*/ale_linters/*'
 
 exit $RETURN_CODE
diff --git a/test/smoke_test.vader b/test/smoke_test.vader
index 1cbf512d..2708c86f 100644
--- a/test/smoke_test.vader
+++ b/test/smoke_test.vader
@@ -35,7 +35,6 @@ After:
 
   unlet! g:i
   unlet! g:results
-  unlet! g:item
   unlet! g:expected_results
 
   delfunction TestCallback
@@ -69,13 +68,7 @@ Execute(Linters should run with the default options):
     call ale#Lint()
     call ale#engine#WaitForJobs(2000)
 
-    let g:results = getloclist(0)
-
-    for g:item in g:results
-      if has_key(g:item, 'module')
-        call remove(g:item, 'module')
-      endif
-    endfor
+    let g:results = ale#test#GetLoclistWithoutModule()
 
     if g:results == g:expected_results
       break
@@ -142,7 +135,7 @@ Execute(Linters should run in PowerShell too):
     \   'pattern': '',
     \   'valid': 1,
     \ },
-    \], getloclist(0)
+    \], ale#test#GetLoclistWithoutModule()
   endif
 
 Execute(Previous errors should be removed when linters change):
@@ -176,13 +169,7 @@ Execute(Previous errors should be removed when linters change):
     call ale#Lint()
     call ale#engine#WaitForJobs(2000)
 
-    let g:results = getloclist(0)
-
-    for g:item in g:results
-      if has_key(g:item, 'module')
-        call remove(g:item, 'module')
-      endif
-    endfor
+    let g:results = ale#test#GetLoclistWithoutModule()
 
     if g:results == g:expected_results
       break
diff --git a/test/test_ale_lint_command.vader b/test/test_ale_lint_command.vader
index 6434e45f..bc2ebabe 100644
--- a/test/test_ale_lint_command.vader
+++ b/test/test_ale_lint_command.vader
@@ -66,10 +66,10 @@ Execute(ALELint should run the linters):
       sleep 1ms
     endif
 
-    if getloclist(0) == g:expected_loclist
+    if ale#test#GetLoclistWithoutModule() == g:expected_loclist
       break
     endif
   endfor
 
   " Check the loclist
-  AssertEqual g:expected_loclist, getloclist(0)
+  AssertEqual g:expected_loclist, ale#test#GetLoclistWithoutModule()
diff --git a/test/test_ale_toggle.vader b/test/test_ale_toggle.vader
index 3b3c509c..db891009 100644
--- a/test/test_ale_toggle.vader
+++ b/test/test_ale_toggle.vader
@@ -115,7 +115,7 @@ Execute(ALEToggle should reset everything and then run again):
   ALELint
 
   " First check that everything is there...
-  AssertEqual g:expected_loclist, getloclist(0)
+  AssertEqual g:expected_loclist, ale#test#GetLoclistWithoutModule()
   AssertEqual [0, [[2, 1000001, 'ALEErrorSign']]], ale#sign#FindCurrentSigns(bufnr('%'))
   AssertEqual
   \ [{'group': 'ALEError', 'pos1': [2, 3, 1]}],
@@ -128,7 +128,7 @@ Execute(ALEToggle should reset everything and then run again):
 
   " Everything should be cleared.
   Assert !has_key(g:ale_buffer_info, bufnr('')), 'The g:ale_buffer_info Dictionary was not removed'
-  AssertEqual [], getloclist(0), 'The loclist was not cleared'
+  AssertEqual [], ale#test#GetLoclistWithoutModule(), 'The loclist was not cleared'
   AssertEqual [0, []], ale#sign#FindCurrentSigns(bufnr('%')), 'The signs were not cleared'
   AssertEqual [], getmatches(), 'The highlights were not cleared'
   AssertEqual g:expected_groups, ParseAuGroups()
@@ -136,7 +136,7 @@ Execute(ALEToggle should reset everything and then run again):
   " Toggle ALE on, everything should be set up and run again.
   ALEToggle
 
-  AssertEqual g:expected_loclist, getloclist(0)
+  AssertEqual g:expected_loclist, ale#test#GetLoclistWithoutModule()
   AssertEqual [0, [[2, 1000001, 'ALEErrorSign']]], ale#sign#FindCurrentSigns(bufnr('%'))
   AssertEqual
   \ [{'group': 'ALEError', 'pos1': [2, 3, 1]}],
@@ -189,16 +189,16 @@ Execute(ALEToggle should skip filename keys and preserve them):
 Execute(ALEDisable should reset everything and stay disabled):
   ALELint
 
-  AssertEqual g:expected_loclist, getloclist(0)
+  AssertEqual g:expected_loclist, ale#test#GetLoclistWithoutModule()
 
   ALEDisable
 
-  AssertEqual [], getloclist(0)
+  AssertEqual [], ale#test#GetLoclistWithoutModule()
   AssertEqual 0, g:ale_enabled
 
   ALEDisable
 
-  AssertEqual [], getloclist(0)
+  AssertEqual [], ale#test#GetLoclistWithoutModule()
   AssertEqual 0, g:ale_enabled
 
 Execute(ALEEnable should enable ALE and lint again):
@@ -206,7 +206,7 @@ Execute(ALEEnable should enable ALE and lint again):
 
   ALEEnable
 
-  AssertEqual g:expected_loclist, getloclist(0)
+  AssertEqual g:expected_loclist, ale#test#GetLoclistWithoutModule()
   AssertEqual 1, g:ale_enabled
 
 Execute(ALEReset should reset everything for a buffer):
@@ -215,7 +215,7 @@ Execute(ALEReset should reset everything for a buffer):
   ALELint
 
   " First check that everything is there...
-  AssertEqual g:expected_loclist, getloclist(0)
+  AssertEqual g:expected_loclist, ale#test#GetLoclistWithoutModule()
   AssertEqual [0, [[2, 1000001, 'ALEErrorSign']]], ale#sign#FindCurrentSigns(bufnr('%'))
   AssertEqual
   \ [{'group': 'ALEError', 'pos1': [2, 3, 1]}],
@@ -227,7 +227,7 @@ Execute(ALEReset should reset everything for a buffer):
 
   " Everything should be cleared.
   Assert !has_key(g:ale_buffer_info, bufnr('')), 'The g:ale_buffer_info Dictionary was not removed'
-  AssertEqual [], getloclist(0), 'The loclist was not cleared'
+  AssertEqual [], ale#test#GetLoclistWithoutModule(), 'The loclist was not cleared'
   AssertEqual [0, []], ale#sign#FindCurrentSigns(bufnr('%')), 'The signs were not cleared'
   AssertEqual [], getmatches(), 'The highlights were not cleared'
 
@@ -239,7 +239,7 @@ Execute(ALEToggleBuffer should reset everything and then run again):
   ALELint
 
   " First check that everything is there...
-  AssertEqual g:expected_loclist, getloclist(0)
+  AssertEqual g:expected_loclist, ale#test#GetLoclistWithoutModule()
   AssertEqual [0, [[2, 1000001, 'ALEErrorSign']]], ale#sign#FindCurrentSigns(bufnr('%'))
   AssertEqual
   \ [{'group': 'ALEError', 'pos1': [2, 3, 1]}],
@@ -251,14 +251,14 @@ Execute(ALEToggleBuffer should reset everything and then run again):
 
   " Everything should be cleared.
   Assert !has_key(g:ale_buffer_info, bufnr('')), 'The g:ale_buffer_info Dictionary was not removed'
-  AssertEqual [], getloclist(0), 'The loclist was not cleared'
+  AssertEqual [], ale#test#GetLoclistWithoutModule(), 'The loclist was not cleared'
   AssertEqual [0, []], ale#sign#FindCurrentSigns(bufnr('%')), 'The signs were not cleared'
   AssertEqual [], getmatches(), 'The highlights were not cleared'
 
   " Toggle ALE on, everything should be set up and run again.
   ALEToggleBuffer
 
-  AssertEqual g:expected_loclist, getloclist(0)
+  AssertEqual g:expected_loclist, ale#test#GetLoclistWithoutModule()
   AssertEqual [0, [[2, 1000001, 'ALEErrorSign']]], ale#sign#FindCurrentSigns(bufnr('%'))
   AssertEqual
   \ [{'group': 'ALEError', 'pos1': [2, 3, 1]}],
@@ -269,11 +269,11 @@ Execute(ALEToggleBuffer should reset everything and then run again):
 Execute(ALEDisableBuffer should reset everything and stay disabled):
   ALELint
 
-  AssertEqual g:expected_loclist, getloclist(0)
+  AssertEqual g:expected_loclist, ale#test#GetLoclistWithoutModule()
 
   ALEDisableBuffer
 
-  AssertEqual [], getloclist(0)
+  AssertEqual [], ale#test#GetLoclistWithoutModule()
   AssertEqual 0, b:ale_enabled
 
 Execute(ALEEnableBuffer should enable ALE and lint again):
@@ -281,7 +281,7 @@ Execute(ALEEnableBuffer should enable ALE and lint again):
 
   ALEEnableBuffer
 
-  AssertEqual g:expected_loclist, getloclist(0)
+  AssertEqual g:expected_loclist, ale#test#GetLoclistWithoutModule()
   AssertEqual 1, b:ale_enabled
 
 Execute(ALEEnableBuffer should complain when ALE is disabled globally):
@@ -292,7 +292,7 @@ Execute(ALEEnableBuffer should complain when ALE is disabled globally):
     ALEEnableBuffer
   redir END
 
-  AssertEqual [], getloclist(0)
+  AssertEqual [], ale#test#GetLoclistWithoutModule()
   AssertEqual 0, b:ale_enabled
   AssertEqual 0, g:ale_enabled
   AssertEqual
@@ -305,7 +305,7 @@ Execute(ALEResetBuffer should reset everything for a buffer):
   ALELint
 
   " First check that everything is there...
-  AssertEqual g:expected_loclist, getloclist(0)
+  AssertEqual g:expected_loclist, ale#test#GetLoclistWithoutModule()
   AssertEqual [0, [[2, 1000001, 'ALEErrorSign']]], ale#sign#FindCurrentSigns(bufnr('%'))
   AssertEqual
   \ [{'group': 'ALEError', 'pos1': [2, 3, 1]}],
@@ -317,7 +317,7 @@ Execute(ALEResetBuffer should reset everything for a buffer):
 
   " Everything should be cleared.
   Assert !has_key(g:ale_buffer_info, bufnr('')), 'The g:ale_buffer_info Dictionary was not removed'
-  AssertEqual [], getloclist(0), 'The loclist was not cleared'
+  AssertEqual [], ale#test#GetLoclistWithoutModule(), 'The loclist was not cleared'
   AssertEqual [0, []], ale#sign#FindCurrentSigns(bufnr('%')), 'The signs were not cleared'
   AssertEqual [], getmatches(), 'The highlights were not cleared'
 
@@ -326,40 +326,60 @@ Execute(ALEResetBuffer should reset everything for a buffer):
 
 Execute(Disabling ALE should disable balloons):
   " These tests won't run in the console, but we can run them manually in GVim.
-  if has('balloon_eval') && has('gui_running') ||
-  \  has('balloon_eval_term') && !has('gui_running')
+  if has('balloon_eval') && has('gui_running')
+  \|| (has('balloon_eval_term') && !has('gui_running'))
     call ale#linter#Reset()
 
     " Enable balloons, so we can check the expr value.
     call ale#balloon#Enable()
 
-    AssertEqual 1, &ballooneval
+    if has('balloon_eval') && has('gui_running')
+      AssertEqual 1, &ballooneval
+    else
+      AssertEqual 1, &balloonevalterm
+    endif
+
     AssertEqual 'ale#balloon#Expr()', &balloonexpr
 
     " Toggle ALE off.
     ALEToggle
 
     " The balloon settings should be reset.
-    AssertEqual 0, &ballooneval
+    if has('balloon_eval') && has('gui_running')
+      AssertEqual 0, &ballooneval
+    else
+      AssertEqual 0, &balloonevalterm
+    endif
+
     AssertEqual '', &balloonexpr
   endif
 
 Execute(Enabling ALE should enable balloons if the setting is on):
-  if has('balloon_eval') && has('gui_running') ||
-  \  has('balloon_eval_term') && !has('gui_running')
+  if has('balloon_eval') && has('gui_running')
+  \|| (has('balloon_eval_term') && !has('gui_running'))
     call ale#linter#Reset()
     call ale#balloon#Disable()
     ALEDisable
     let g:ale_set_balloons = 0
     ALEEnable
 
-    AssertEqual 0, &ballooneval
+    if has('balloon_eval') && has('gui_running')
+      AssertEqual 0, &ballooneval
+    else
+      AssertEqual 0, &balloonevalterm
+    endif
+
     AssertEqual '', &balloonexpr
 
     ALEDisable
     let g:ale_set_balloons = 1
     ALEEnable
 
-    AssertEqual 1, &ballooneval
+    if has('balloon_eval') && has('gui_running')
+      AssertEqual 1, &ballooneval
+    else
+      AssertEqual 1, &balloonevalterm
+    endif
+
     AssertEqual 'ale#balloon#Expr()', &balloonexpr
   endif
diff --git a/test/test_ale_var.vader b/test/test_ale_var.vader
index 5f42fe95..419a9983 100644
--- a/test/test_ale_var.vader
+++ b/test/test_ale_var.vader
@@ -5,8 +5,6 @@ After:
   unlet! g:ale_some_variable
   unlet! b:undefined_variable_name
 
-  let g:ale_fix_buffer_data = {}
-
 Execute(ale#Var should return global variables):
   AssertEqual 'abc', ale#Var(bufnr(''), 'some_variable')
 
@@ -24,13 +22,3 @@ Execute(ale#Var should throw exceptions for undefined variables):
   let b:undefined_variable_name = 'def'
 
   AssertThrows call ale#Var(bufnr(''), 'undefined_variable_name')
-
-Execute(ale#Var return variables from deleted buffers, saved for fixing things):
-  let g:ale_fix_buffer_data[1347347] = {'vars': {'ale_some_variable': 'def'}}
-
-  AssertEqual 'def', ale#Var(1347347, 'some_variable')
-
-Execute(ale#Var should return the global variable for unknown variables):
-  let g:ale_fix_buffer_data = {}
-
-  AssertEqual 'abc', ale#Var(1347347, 'some_variable')
diff --git a/test/test_c_import_paths.vader b/test/test_c_import_paths.vader
index f2a06781..0490dec6 100644
--- a/test/test_c_import_paths.vader
+++ b/test/test_c_import_paths.vader
@@ -1,8 +1,21 @@
 Before:
+  " Make sure the c.vim file is loaded first.
+  call ale#c#FindProjectRoot(bufnr(''))
+
   Save g:ale_c_gcc_options
   Save g:ale_c_clang_options
   Save g:ale_cpp_gcc_options
   Save g:ale_cpp_clang_options
+  Save g:__ale_c_project_filenames
+
+  let g:original_project_filenames = g:__ale_c_project_filenames
+
+  " Remove the .git/HEAD dir for C import paths for these tests.
+  " The tests run inside of a git repo.
+  let g:__ale_c_project_filenames = filter(
+  \ copy(g:__ale_c_project_filenames),
+  \ 'v:val isnot# ''.git/HEAD'''
+  \)
 
   call ale#test#SetDirectory('/testplugin/test')
 
@@ -14,23 +27,11 @@ Before:
 After:
   Restore
 
+  unlet! g:original_project_filenames
+
   call ale#test#RestoreDirectory()
   call ale#linter#Reset()
 
-" Run this only once for this series of tests. The cleanup Execute step
-" will run at the bottom of this file.
-"
-" We need to move .git/HEAD away so we don't match it, as we need to test
-" functions which look for .git/HEAD.
-Execute(Move .git/HEAD to a temp dir):
-  let g:temp_head_filename = tempname()
-  let g:head_filename = findfile('.git/HEAD', ';')
-
-  if !empty(g:head_filename)
-    call writefile(readfile(g:head_filename, 'b'), g:temp_head_filename, 'b')
-    call delete(g:head_filename)
-  endif
-
 Execute(The C GCC handler should include 'include' directories for projects with a Makefile):
   runtime! ale_linters/c/gcc.vim
 
@@ -239,27 +240,6 @@ Execute(The C++ Clang handler should include root directories for projects with
   \   . ' -'
   \ , ale_linters#cpp#clang#GetCommand(bufnr(''), [])
 
-Execute(The C++ Clang handler shoud use the include directory based on the .git location):
-  runtime! ale_linters/cpp/clang.vim
-
-  if !isdirectory(g:dir . '/test_c_projects/git_and_nested_makefiles/.git')
-    call mkdir(g:dir . '/test_c_projects/git_and_nested_makefiles/.git')
-  endif
-
-  if !filereadable(g:dir . '/test_c_projects/git_and_nested_makefiles/.git/HEAD')
-    call writefile([], g:dir . '/test_c_projects/git_and_nested_makefiles/.git/HEAD')
-  endif
-
-  call ale#test#SetFilename('test_c_projects/git_and_nested_makefiles/src/file.cpp')
-
-  AssertEqual
-  \   ale#Escape('clang++')
-  \   . ' -S -x c++ -fsyntax-only '
-  \   . '-iquote ' . ale#Escape(ale#path#Simplify(g:dir .  '/test_c_projects/git_and_nested_makefiles/src')) . ' '
-  \   . ' -I' . ale#Escape(ale#path#Simplify(g:dir .  '/test_c_projects/git_and_nested_makefiles/include')) . ' '
-  \   . ' -'
-  \ , ale_linters#cpp#clang#GetCommand(bufnr(''), [])
-
 Execute(The C++ ClangTidy handler should include json folders for projects with suitable build directory in them):
   runtime! ale_linters/cpp/clangtidy.vim
 
@@ -270,12 +250,3 @@ Execute(The C++ ClangTidy handler should include json folders for projects with
   \   . ' -checks=' . ale#Escape('*') . ' %s '
   \   . '-p ' . ale#Escape(ale#path#Simplify(g:dir . '/test_c_projects/json_project/build'))
   \ , ale_linters#cpp#clangtidy#GetCommand(bufnr(''))
-
-Execute(Move .git/HEAD back):
-  if !empty(g:head_filename)
-    call writefile(readfile(g:temp_head_filename, 'b'), g:head_filename, 'b')
-    call delete(g:temp_head_filename)
-  endif
-
-  unlet! g:temp_head_filename
-  unlet! g:head_filename
diff --git a/test/test_engine_lsp_response_handling.vader b/test/test_engine_lsp_response_handling.vader
index 18bad0a1..517d82c0 100644
--- a/test/test_engine_lsp_response_handling.vader
+++ b/test/test_engine_lsp_response_handling.vader
@@ -68,7 +68,7 @@ Execute(tsserver syntax error responses should be handled correctly):
   \     'pattern': '',
   \   },
   \ ],
-  \ getloclist(0)
+  \ ale#test#GetLoclistWithoutModule()
 
   " After we get empty syntax errors, we should clear them.
   call ale#lsp_linter#HandleLSPResponse(1, {
@@ -85,7 +85,7 @@ Execute(tsserver syntax error responses should be handled correctly):
   AssertEqual
   \ [
   \ ],
-  \ getloclist(0)
+  \ ale#test#GetLoclistWithoutModule()
 
 Execute(tsserver semantic error responses should be handled correctly):
   runtime ale_linters/typescript/tsserver.vim
@@ -141,7 +141,7 @@ Execute(tsserver semantic error responses should be handled correctly):
   \     'pattern': '',
   \   },
   \ ],
-  \ getloclist(0)
+  \ ale#test#GetLoclistWithoutModule()
 
   " After we get empty syntax errors, we should clear them.
   call ale#lsp_linter#HandleLSPResponse(1, {
@@ -158,7 +158,7 @@ Execute(tsserver semantic error responses should be handled correctly):
   AssertEqual
   \ [
   \ ],
-  \ getloclist(0)
+  \ ale#test#GetLoclistWithoutModule()
 
 Execute(LSP errors should be logged in the history):
   call ale#lsp_linter#SetLSPLinterMap({'347': 'foobar'})
diff --git a/test/test_errors_removed_after_filetype_changed.vader b/test/test_errors_removed_after_filetype_changed.vader
index afd882b1..651a74f2 100644
--- a/test/test_errors_removed_after_filetype_changed.vader
+++ b/test/test_errors_removed_after_filetype_changed.vader
@@ -53,7 +53,7 @@ Execute(Error should be removed when the filetype changes to something else we c
   call ale#Queue(0)
   sleep 1ms
 
-  AssertEqual 1, len(getloclist(0))
+  AssertEqual 1, len(ale#test#GetLoclistWithoutModule())
 
   noautocmd let &filetype = 'foobar2'
 
@@ -61,11 +61,11 @@ Execute(Error should be removed when the filetype changes to something else we c
   sleep 1ms
 
   " We should get some items from the second filetype.
-  AssertEqual 1, len(getloclist(0))
+  AssertEqual 1, len(ale#test#GetLoclistWithoutModule())
 
   noautocmd let &filetype = 'xxx'
 
   call ale#Queue(0)
   sleep 1ms
 
-  AssertEqual 0, len(getloclist(0))
+  AssertEqual 0, len(ale#test#GetLoclistWithoutModule())
diff --git a/test/test_filetype_linter_defaults.vader b/test/test_filetype_linter_defaults.vader
index ea4a05fb..4f190226 100644
--- a/test/test_filetype_linter_defaults.vader
+++ b/test/test_filetype_linter_defaults.vader
@@ -22,7 +22,7 @@ Execute(The defaults for the csh filetype should be correct):
   AssertEqual [], GetLinterNames('csh')
 
 Execute(The defaults for the go filetype should be correct):
-  AssertEqual ['gofmt', 'golint', 'go vet'], GetLinterNames('go')
+  AssertEqual ['gofmt', 'golint', 'govet'], GetLinterNames('go')
 
   let g:ale_linters_explicit = 1
 
diff --git a/test/test_find_references.vader b/test/test_find_references.vader
index 150e0471..ecced068 100644
--- a/test/test_find_references.vader
+++ b/test/test_find_references.vader
@@ -3,20 +3,20 @@ Before:
   call ale#test#SetFilename('dummy.txt')
 
   let g:old_filename = expand('%:p')
-  let g:Callback = 0
+  let g:Callback = ''
   let g:expr_list = []
   let g:message_list = []
   let g:preview_called = 0
   let g:item_list = []
+  let g:capability_checked = ''
+  let g:WaitCallback = v:null
 
   runtime autoload/ale/linter.vim
   runtime autoload/ale/lsp.vim
   runtime autoload/ale/util.vim
   runtime autoload/ale/preview.vim
 
-  function! ale#lsp_linter#StartLSP(buffer, linter, callback) abort
-    let g:Callback = a:callback
-
+  function! ale#lsp_linter#StartLSP(buffer, linter) abort
     let l:conn = ale#lsp#NewConnection({})
     let l:conn.id = 347
     let l:conn.open_documents = {a:buffer : -1}
@@ -29,6 +29,15 @@ Before:
     \}
   endfunction
 
+  function! ale#lsp#WaitForCapability(conn_id, project_root, capability, callback) abort
+    let g:capability_checked = a:capability
+    let g:WaitCallback = a:callback
+  endfunction
+
+  function! ale#lsp#RegisterCallback(conn_id, callback) abort
+    let g:Callback = a:callback
+  endfunction
+
   function! ale#lsp#Send(conn_id, message, root) abort
     call add(g:message_list, a:message)
 
@@ -50,6 +59,8 @@ After:
   call ale#test#RestoreDirectory()
   call ale#linter#Reset()
 
+  unlet! g:capability_checked
+  unlet! g:WaitCallback
   unlet! g:old_filename
   unlet! g:Callback
   unlet! g:message_list
@@ -152,6 +163,13 @@ Execute(tsserver reference requests should be sent):
 
   ALEFindReferences
 
+  " We shouldn't register the callback yet.
+  AssertEqual '''''', string(g:Callback)
+
+  AssertEqual type(function('type')), type(g:WaitCallback)
+  AssertEqual 'references', g:capability_checked
+  call call(g:WaitCallback, [347, '/foo/bar'])
+
   AssertEqual
   \ 'function(''ale#references#HandleTSServerResponse'')',
   \ string(g:Callback)
@@ -226,6 +244,13 @@ Execute(LSP reference requests should be sent):
 
   ALEFindReferences
 
+  " We shouldn't register the callback yet.
+  AssertEqual '''''', string(g:Callback)
+
+  AssertEqual type(function('type')), type(g:WaitCallback)
+  AssertEqual 'references', g:capability_checked
+  call call(g:WaitCallback, [347, '/foo/bar'])
+
   AssertEqual
   \ 'function(''ale#references#HandleLSPResponse'')',
   \ string(g:Callback)
diff --git a/test/test_go_to_definition.vader b/test/test_go_to_definition.vader
index 749f4d7e..7f0e3fcb 100644
--- a/test/test_go_to_definition.vader
+++ b/test/test_go_to_definition.vader
@@ -3,17 +3,17 @@ Before:
   call ale#test#SetFilename('dummy.txt')
 
   let g:old_filename = expand('%:p')
-  let g:Callback = 0
+  let g:Callback = ''
   let g:message_list = []
   let g:expr_list = []
+  let g:capability_checked = ''
+  let g:WaitCallback = v:null
 
   runtime autoload/ale/linter.vim
   runtime autoload/ale/lsp.vim
   runtime autoload/ale/util.vim
 
-  function! ale#lsp_linter#StartLSP(buffer, linter, callback) abort
-    let g:Callback = a:callback
-
+  function! ale#lsp_linter#StartLSP(buffer, linter) abort
     let l:conn = ale#lsp#NewConnection({})
     let l:conn.id = 347
     let l:conn.open_documents = {a:buffer : -1}
@@ -26,6 +26,15 @@ Before:
     \}
   endfunction
 
+  function! ale#lsp#WaitForCapability(conn_id, project_root, capability, callback) abort
+    let g:capability_checked = a:capability
+    let g:WaitCallback = a:callback
+  endfunction
+
+  function! ale#lsp#RegisterCallback(conn_id, callback) abort
+    let g:Callback = a:callback
+  endfunction
+
   function! ale#lsp#Send(conn_id, message, root) abort
     call add(g:message_list, a:message)
 
@@ -42,6 +51,8 @@ After:
   call ale#test#RestoreDirectory()
   call ale#linter#Reset()
 
+  unlet! g:capability_checked
+  unlet! g:WaitCallback
   unlet! g:old_filename
   unlet! g:Callback
   unlet! g:message_list
@@ -137,6 +148,13 @@ Execute(tsserver completion requests should be sent):
 
   ALEGoToDefinition
 
+  " We shouldn't register the callback yet.
+  AssertEqual '''''', string(g:Callback)
+
+  AssertEqual type(function('type')), type(g:WaitCallback)
+  AssertEqual 'definition', g:capability_checked
+  call call(g:WaitCallback, [347, '/foo/bar'])
+
   AssertEqual
   \ 'function(''ale#definition#HandleTSServerResponse'')',
   \ string(g:Callback)
@@ -151,6 +169,13 @@ Execute(tsserver tab completion requests should be sent):
 
   ALEGoToDefinitionInTab
 
+  " We shouldn't register the callback yet.
+  AssertEqual '''''', string(g:Callback)
+
+  AssertEqual type(function('type')), type(g:WaitCallback)
+  AssertEqual 'definition', g:capability_checked
+  call call(g:WaitCallback, [347, '/foo/bar'])
+
   AssertEqual
   \ 'function(''ale#definition#HandleTSServerResponse'')',
   \ string(g:Callback)
@@ -276,6 +301,13 @@ Execute(LSP completion requests should be sent):
 
   ALEGoToDefinition
 
+  " We shouldn't register the callback yet.
+  AssertEqual '''''', string(g:Callback)
+
+  AssertEqual type(function('type')), type(g:WaitCallback)
+  AssertEqual 'definition', g:capability_checked
+  call call(g:WaitCallback, [347, '/foo/bar'])
+
   AssertEqual
   \ 'function(''ale#definition#HandleLSPResponse'')',
   \ string(g:Callback)
@@ -305,6 +337,13 @@ Execute(LSP tab completion requests should be sent):
 
   ALEGoToDefinitionInTab
 
+  " We shouldn't register the callback yet.
+  AssertEqual '''''', string(g:Callback)
+
+  AssertEqual type(function('type')), type(g:WaitCallback)
+  AssertEqual 'definition', g:capability_checked
+  call call(g:WaitCallback, [347, '/foo/bar'])
+
   AssertEqual
   \ 'function(''ale#definition#HandleLSPResponse'')',
   \ string(g:Callback)
diff --git a/test/test_lint_file_linters.vader b/test/test_lint_file_linters.vader
index 14339e21..ca093aa8 100644
--- a/test/test_lint_file_linters.vader
+++ b/test/test_lint_file_linters.vader
@@ -51,7 +51,7 @@ Before:
   function! GetSimplerLoclist()
     let l:loclist = []
 
-    for l:item in getloclist(0)
+    for l:item in ale#test#GetLoclistWithoutModule()
       call add(l:loclist, {
       \ 'lnum': l:item.lnum,
       \ 'col': l:item.col,
diff --git a/test/test_lint_on_enter_when_file_changed.vader b/test/test_lint_on_enter_when_file_changed.vader
index 8a54d9b8..67f43c17 100644
--- a/test/test_lint_on_enter_when_file_changed.vader
+++ b/test/test_lint_on_enter_when_file_changed.vader
@@ -61,7 +61,7 @@ Execute(The file changed event function should lint the current buffer when it h
   \   'nr': -1,
   \   'pattern': '',
   \   'valid': 1,
-  \ }], getloclist(0)
+  \ }], ale#test#GetLoclistWithoutModule()
 
 Execute(The buffer should be checked after entering it after the file has changed):
   let b:ale_file_changed = 1
@@ -79,4 +79,4 @@ Execute(The buffer should be checked after entering it after the file has change
   \   'nr': -1,
   \   'pattern': '',
   \   'valid': 1,
-  \ }], getloclist(0)
+  \ }], ale#test#GetLoclistWithoutModule()
diff --git a/test/test_list_formatting.vader b/test/test_list_formatting.vader
index 0c52f10f..dcefac53 100644
--- a/test/test_list_formatting.vader
+++ b/test/test_list_formatting.vader
@@ -53,7 +53,7 @@ Execute(Formatting with codes should work for the loclist):
   \     'text': 'nocode',
   \   },
   \ ],
-  \ getloclist(0)
+  \ ale#test#GetLoclistWithoutModule()
 
   call remove(g:loclist, 0)
   call AddItem({'text': 'withcode', 'code': 'E123'})
@@ -73,7 +73,7 @@ Execute(Formatting with codes should work for the loclist):
   \     'text': 'E123: withcode',
   \   },
   \ ],
-  \ getloclist(0)
+  \ ale#test#GetLoclistWithoutModule()
 
 Execute(Formatting with codes should work for the quickfix list):
   let g:ale_set_loclist = 0
@@ -96,7 +96,7 @@ Execute(Formatting with codes should work for the quickfix list):
   \     'text': 'nocode',
   \   },
   \ ],
-  \ getqflist()
+  \ ale#test#GetQflistWithoutModule()
 
   call remove(g:loclist, 0)
   call AddItem({'text': 'withcode', 'code': 'E123'})
@@ -116,7 +116,7 @@ Execute(Formatting with codes should work for the quickfix list):
   \     'text': 'E123: withcode',
   \   },
   \ ],
-  \ getqflist()
+  \ ale#test#GetQflistWithoutModule()
 
 Execute(Formatting with the linter name should work for the loclist):
   let g:ale_loclist_msg_format = '(%linter%) %s'
@@ -138,7 +138,7 @@ Execute(Formatting with the linter name should work for the loclist):
   \     'text': '(some_linter) whatever',
   \   },
   \ ],
-  \ getloclist(0)
+  \ ale#test#GetLoclistWithoutModule()
 
 Execute(Formatting with the linter name should work for the quickfix list):
   let g:ale_loclist_msg_format = '(%linter%) %s'
@@ -162,7 +162,7 @@ Execute(Formatting with the linter name should work for the quickfix list):
   \     'text': '(some_linter) whatever',
   \   },
   \ ],
-  \ getqflist()
+  \ ale#test#GetQflistWithoutModule()
 
 Execute(The buffer loclist format option should take precedence):
   let g:ale_loclist_msg_format = '(%linter%) %s'
@@ -185,4 +185,4 @@ Execute(The buffer loclist format option should take precedence):
   \     'text': 'FOO whatever',
   \   },
   \ ],
-  \ getloclist(0)
+  \ ale#test#GetLoclistWithoutModule()
diff --git a/test/test_list_opening.vader b/test/test_list_opening.vader
index a24e8de9..8f0b2fd5 100644
--- a/test/test_list_opening.vader
+++ b/test/test_list_opening.vader
@@ -120,7 +120,7 @@ Execute(The quickfix window should be vertical for the loclist with appropriate
 
   call ale#list#SetLists(bufnr('%'), g:loclist)
 
-  AssertEqual 1, GetQuickfixIsVertical(b:ale_list_window_size)
+  AssertEqual 1, GetQuickfixIsVertical(8)
 
 Execute(The quickfix window should be horizontal for the loclist with appropriate variables):
   let g:ale_open_list = 1
@@ -129,7 +129,7 @@ Execute(The quickfix window should be horizontal for the loclist with appropriat
 
   call ale#list#SetLists(bufnr('%'), g:loclist)
 
-  AssertEqual 0, GetQuickfixIsVertical(b:ale_list_window_size)
+  AssertEqual 0, GetQuickfixIsVertical(8)
 
 Execute(The quickfix window should stay open for just the loclist):
   let g:ale_open_list = 1
@@ -207,7 +207,7 @@ Execute(The quickfix window should be vertical for the quickfix with appropriate
 
   call ale#list#SetLists(bufnr('%'), g:loclist)
 
-  AssertEqual 1, GetQuickfixIsVertical(b:ale_list_window_size)
+  AssertEqual 1, GetQuickfixIsVertical(8)
 
 Execute(The quickfix window should be horizontal for the quickfix with appropriate variables):
   let g:ale_open_list = 1
@@ -216,7 +216,7 @@ Execute(The quickfix window should be horizontal for the quickfix with appropria
 
   call ale#list#SetLists(bufnr('%'), g:loclist)
 
-  AssertEqual 0, GetQuickfixIsVertical(b:ale_list_window_size)
+  AssertEqual 0, GetQuickfixIsVertical(8)
 
 Execute(The buffer ale_open_list option should be respected):
   let b:ale_open_list = 1
diff --git a/test/test_list_titles.vader b/test/test_list_titles.vader
index d521906f..1f0b2308 100644
--- a/test/test_list_titles.vader
+++ b/test/test_list_titles.vader
@@ -38,7 +38,7 @@ Execute(The loclist titles should be set appropriately):
   \ 'nr': 0,
   \ 'type': 'E',
   \ 'pattern': '',
-  \}], getloclist(0)
+  \}], ale#test#GetLoclistWithoutModule()
 
   if !has('nvim')
     AssertEqual
@@ -68,7 +68,7 @@ Execute(The quickfix titles should be set appropriately):
   \ 'nr': 0,
   \ 'type': 'E',
   \ 'pattern': '',
-  \}], getqflist()
+  \}], ale#test#GetQflistWithoutModule()
 
   if !has('nvim')
     AssertEqual
diff --git a/test/test_no_linting_on_write_quit.vader b/test/test_no_linting_on_write_quit.vader
index db05bd7d..12ef38ed 100644
--- a/test/test_no_linting_on_write_quit.vader
+++ b/test/test_no_linting_on_write_quit.vader
@@ -59,14 +59,14 @@ Execute(No linting should be done on :wq or :x):
   " First try just the SaveEvent, to be sure that we set errors in the test.
   call ale#events#SaveEvent(bufnr(''))
 
-  AssertEqual 1, len(getloclist(0))
+  AssertEqual 1, len(ale#test#GetLoclistWithoutModule())
 
   " Now try doing it again, but where we run the quit event first.
   call setloclist(0, [])
   call ale#events#QuitEvent(bufnr(''))
   call ale#events#SaveEvent(bufnr(''))
 
-  AssertEqual [], getloclist(0)
+  AssertEqual [], ale#test#GetLoclistWithoutModule()
 
 Execute(No linting should be for :w after :q fails):
   let g:ale_lint_on_save = 1
@@ -79,7 +79,7 @@ Execute(No linting should be for :w after :q fails):
 
   call ale#events#SaveEvent(bufnr(''))
 
-  AssertEqual 1, len(getloclist(0))
+  AssertEqual 1, len(ale#test#GetLoclistWithoutModule())
 
 Execute(No linting should be done on :wq or :x after fixing files):
   let g:ale_lint_on_save = 0
@@ -87,14 +87,14 @@ Execute(No linting should be done on :wq or :x after fixing files):
 
   call ale#events#SaveEvent(bufnr(''))
 
-  AssertEqual 1, len(getloclist(0))
+  AssertEqual 1, len(ale#test#GetLoclistWithoutModule())
 
   " Now try doing it again, but where we run the quit event first.
   call setloclist(0, [])
   call ale#events#QuitEvent(bufnr(''))
   call ale#events#SaveEvent(bufnr(''))
 
-  AssertEqual [], getloclist(0)
+  AssertEqual [], ale#test#GetLoclistWithoutModule()
 
 Execute(Linting should be done after :q fails and fixing files):
   let g:ale_lint_on_save = 0
@@ -107,4 +107,4 @@ Execute(Linting should be done after :q fails and fixing files):
 
   call ale#events#SaveEvent(bufnr(''))
 
-  AssertEqual 1, len(getloclist(0))
+  AssertEqual 1, len(ale#test#GetLoclistWithoutModule())
diff --git a/test/test_results_not_cleared_when_opening_loclist.vader b/test/test_results_not_cleared_when_opening_loclist.vader
index dd928fa0..4a53d356 100644
--- a/test/test_results_not_cleared_when_opening_loclist.vader
+++ b/test/test_results_not_cleared_when_opening_loclist.vader
@@ -27,4 +27,4 @@ Execute(The loclist shouldn't be cleared when opening the loclist):
   :lopen
   :q
 
-  AssertEqual 1, len(getloclist(0)), 'The loclist was cleared'
+  AssertEqual 1, len(ale#test#GetLoclistWithoutModule()), 'The loclist was cleared'
diff --git a/test/test_set_list_timers.vader b/test/test_set_list_timers.vader
index f8fcb6a0..e53b97a4 100644
--- a/test/test_set_list_timers.vader
+++ b/test/test_set_list_timers.vader
@@ -26,4 +26,4 @@ Execute(The SetLists function should work when run in a timer):
   \ 'nr': 0,
   \ 'type': 'E',
   \ 'pattern': '',
-  \}], getloclist(0)
+  \}], ale#test#GetLoclistWithoutModule()
diff --git a/test/test_setting_loclist_from_another_buffer.vader b/test/test_setting_loclist_from_another_buffer.vader
index 10a44cce..028ffb1e 100644
--- a/test/test_setting_loclist_from_another_buffer.vader
+++ b/test/test_setting_loclist_from_another_buffer.vader
@@ -21,6 +21,6 @@ Execute(Errors should be set in the loclist for the original buffer, not the new
   \ g:ale_buffer_info[(g:original_buffer)].loclist,
   \ )
 
-  AssertEqual [], getloclist(0)
+  AssertEqual [], ale#test#GetLoclistWithoutModule()
   AssertEqual 1, len(getloclist(bufwinid(g:original_buffer)))
   AssertEqual 'foo', getloclist(bufwinid(g:original_buffer))[0].text
diff --git a/test/test_setting_problems_found_in_previous_buffers.vader b/test/test_setting_problems_found_in_previous_buffers.vader
index 45dfa662..4604005a 100644
--- a/test/test_setting_problems_found_in_previous_buffers.vader
+++ b/test/test_setting_problems_found_in_previous_buffers.vader
@@ -95,4 +95,4 @@ Execute(Problems found from previously opened buffers should be set when linting
   \   {'lnum': 2, 'bufnr': bufnr(''), 'col': 0, 'valid': 1, 'vcol': 0, 'nr': -1, 'type': 'E', 'pattern': '', 'text': 'bar'},
   \   {'lnum': 3, 'bufnr': bufnr(''), 'col': 0, 'valid': 1, 'vcol': 0, 'nr': -1, 'type': 'E', 'pattern': '', 'text': 'baz'},
   \ ],
-  \ getloclist(0)
+  \ ale#test#GetLoclistWithoutModule()