Add support for Dune (#4263)

* Add support for dune

* Add test

* Undo reformatting of Markdown file

* Refer to ale-ocaml-dune from ale.txt

7 files changed, 80 insertions, 0 deletions

diff --git a/autoload/ale/fix/registry.vim b/autoload/ale/fix/registry.vim
index e9b289c6..85fef81d 100644
--- a/autoload/ale/fix/registry.vim
+++ b/autoload/ale/fix/registry.vim
@@ -78,6 +78,11 @@ let s:default_registry = {
 \       'suggested_filetypes': ['dhall'],
 \       'description': 'Standard code formatter for the Dhall language and removing dead code',
 \   },
+\   'dune': {
+\       'function': 'ale#fixers#dune#Fix',
+\       'suggested_filetypes': ['dune'],
+\       'description': 'Fix dune files with dune format',
+\   },
 \   'fecs': {
 \       'function': 'ale#fixers#fecs#Fix',
 \       'suggested_filetypes': ['javascript', 'css', 'html'],
diff --git a/autoload/ale/fixers/dune.vim b/autoload/ale/fixers/dune.vim
new file mode 100644
index 00000000..6ef7ec9f
--- /dev/null
+++ b/autoload/ale/fixers/dune.vim
@@ -0,0 +1,16 @@
+" Author: Albert Peschar <albert@peschar.net>
+" Description: Fix files with dune format.
+
+call ale#Set('ocaml_dune_executable', 'dune')
+call ale#Set('ocaml_dune_options', '')
+
+function! ale#fixers#dune#Fix(buffer) abort
+    let l:executable = ale#Var(a:buffer, 'ocaml_dune_executable')
+    let l:options = ale#Var(a:buffer, 'ocaml_dune_options')
+
+    return {
+    \   'command': ale#Escape(l:executable)
+    \       . ' format'
+    \       . (empty(l:options) ? '' : ' ' . l:options),
+    \}
+endfunction
diff --git a/doc/ale-ocaml.txt b/doc/ale-ocaml.txt
index afbc2386..a361a7b4 100644
--- a/doc/ale-ocaml.txt
+++ b/doc/ale-ocaml.txt
@@ -3,6 +3,26 @@ ALE OCaml Integration                                       *ale-ocaml-options*
 
 
 ===============================================================================
+dune                                                           *ale-ocaml-dune*
+
+  Dune is a build system for OCaml projects. The `dune format` command is
+  supported for automatically formatting `dune` and `dune-project` files.
+
+g:ale_ocaml_dune_executable                       *g:ale_ocaml_dune_executable*
+                                                  *b:ale_ocaml_dune_executable*
+  Type: |String|
+  Default: `'dune'`
+
+  This variable can be set to pass the path to dune.
+
+g:ale_ocaml_dune_options                             *g:ale_ocaml_dune_options*
+                                                     *b:ale_ocaml_dune_options*
+  Type: |String|
+  Default: `''`
+
+  This variable can be set to pass additional options to the dune fixer.
+
+===============================================================================
 merlin                                                       *ale-ocaml-merlin*
 
   To use merlin linter for OCaml source code you need to make sure Merlin for
diff --git a/doc/ale-supported-languages-and-tools.txt b/doc/ale-supported-languages-and-tools.txt
index d66b9a02..a0a7fbd5 100644
--- a/doc/ale-supported-languages-and-tools.txt
+++ b/doc/ale-supported-languages-and-tools.txt
@@ -386,6 +386,7 @@ Notes:
   * `clangd`
   * `uncrustify`
 * OCaml
+  * `dune`
   * `merlin` (see |ale-ocaml-merlin|)
   * `ocamlformat`
   * `ocamllsp`
diff --git a/doc/ale.txt b/doc/ale.txt
index cabca300..828d5e2d 100644
--- a/doc/ale.txt
+++ b/doc/ale.txt
@@ -3041,6 +3041,7 @@ documented in additional help files.
     clangd................................|ale-objcpp-clangd|
     uncrustify............................|ale-objcpp-uncrustify|
   ocaml...................................|ale-ocaml-options|
+    dune..................................|ale-ocaml-dune|
     merlin................................|ale-ocaml-merlin|
     ocamllsp..............................|ale-ocaml-ocamllsp|
     ols...................................|ale-ocaml-ols|
diff --git a/supported-tools.md b/supported-tools.md
index 235f211e..7a71c14c 100644
--- a/supported-tools.md
+++ b/supported-tools.md
@@ -395,6 +395,7 @@ formatting.
   * [clangd](https://clang.llvm.org/extra/clangd.html)
   * [uncrustify](https://github.com/uncrustify/uncrustify)
 * OCaml
+  * [dune](https://dune.build/)
   * [merlin](https://github.com/the-lambda-church/merlin) see `:help ale-ocaml-merlin` for configuration instructions
   * [ocamlformat](https://github.com/ocaml-ppx/ocamlformat)
   * [ocamllsp](https://github.com/ocaml/ocaml-lsp)
diff --git a/test/fixers/test_dune_fixer_callback.vader b/test/fixers/test_dune_fixer_callback.vader
new file mode 100644
index 00000000..7fc0733c
--- /dev/null
+++ b/test/fixers/test_dune_fixer_callback.vader
@@ -0,0 +1,36 @@
+Before:
+  Save g:ale_ocaml_dune_executable
+  Save g:ale_ocaml_dune_options
+
+  " Use an invalid global executable, so we don't match it.
+  let g:ale_ocaml_dune_executable = 'xxxinvalid'
+  let g:ale_ocaml_dune_options = ''
+
+  call ale#test#SetDirectory('/testplugin/test/fixers')
+
+After:
+  Restore
+
+  call ale#test#RestoreDirectory()
+
+Execute(The dune callback should return the correct default values):
+  call ale#test#SetFilename('../test-files/ocaml/testfile.re')
+
+  AssertEqual
+  \ {
+  \   'command': ale#Escape('xxxinvalid')
+  \     . ' format',
+  \ },
+  \ ale#fixers#dune#Fix(bufnr(''))
+
+Execute(The dune callback should include custom dune options):
+  let g:ale_ocaml_dune_options = "--random-option"
+  call ale#test#SetFilename('../test-files/ocaml/testfile.re')
+
+  AssertEqual
+  \ {
+  \   'command': ale#Escape('xxxinvalid')
+  \     . ' format'
+  \     . ' ' . g:ale_ocaml_dune_options,
+  \ },
+  \ ale#fixers#dune#Fix(bufnr(''))