8 files changed, 50 insertions, 16 deletions
diff --git a/ale_linters/elixir/credo.vim b/ale_linters/elixir/credo.vim
index af2ff48a..6e949677 100644
--- a/ale_linters/elixir/credo.vim
+++ b/ale_linters/elixir/credo.vim
@@ -29,9 +29,16 @@ function! ale_linters#elixir#credo#Handle(buffer, lines) abort
     return l:output
 endfunction
 
+function! ale_linters#elixir#credo#GetCommand(buffer) abort
+    let l:project_root = ale#handlers#elixir#FindMixProjectRoot(a:buffer)
+
+    return ale#path#CdString(l:project_root)
+    \ . ' mix help credo && mix credo suggest --format=flycheck --read-from-stdin %s'
+endfunction
+
 call ale#linter#Define('elixir', {
 \   'name': 'credo',
 \   'executable': 'mix',
-\   'command': 'mix help credo && mix credo suggest --format=flycheck --read-from-stdin %s',
+\   'command_callback': 'ale_linters#elixir#credo#GetCommand',
 \   'callback': 'ale_linters#elixir#credo#Handle',
 \})
diff --git a/ale_linters/elixir/dialyxir.vim b/ale_linters/elixir/dialyxir.vim
index bba0ae14..d28d3c70 100644
--- a/ale_linters/elixir/dialyxir.vim
+++ b/ale_linters/elixir/dialyxir.vim
@@ -25,10 +25,17 @@ function! ale_linters#elixir#dialyxir#Handle(buffer, lines) abort
     return l:output
 endfunction
 
+function! ale_linters#elixir#dialyxir#GetCommand(buffer) abort
+    let l:project_root = ale#handlers#elixir#FindMixProjectRoot(a:buffer)
+
+    return ale#path#CdString(l:project_root)
+    \ . ' mix help dialyzer && mix dialyzer'
+endfunction
+
 call ale#linter#Define('elixir', {
 \   'name': 'dialyxir',
 \   'executable': 'mix',
-\   'command': 'mix help dialyzer && mix dialyzer',
+\   'command_callback': 'ale_linters#elixir#dialyxir#GetCommand',
 \   'callback': 'ale_linters#elixir#dialyxir#Handle',
 \})
 
diff --git a/ale_linters/elixir/dogma.vim b/ale_linters/elixir/dogma.vim
index 71cf4f4c..dcfb6f28 100644
--- a/ale_linters/elixir/dogma.vim
+++ b/ale_linters/elixir/dogma.vim
@@ -29,10 +29,17 @@ function! ale_linters#elixir#dogma#Handle(buffer, lines) abort
     return l:output
 endfunction
 
+function! ale_linters#elixir#dogma#GetCommand(buffer) abort
+    let l:project_root = ale#handlers#elixir#FindMixProjectRoot(a:buffer)
+
+    return ale#path#CdString(l:project_root)
+    \ . ' mix help dogma && mix dogma %s --format=flycheck'
+endfunction
+
 call ale#linter#Define('elixir', {
 \   'name': 'dogma',
 \   'executable': 'mix',
-\   'command': 'mix help dogma && mix dogma %s --format=flycheck',
+\   'command_callback': 'ale_linters#elixir#dogma#GetCommand',
 \   'lint_file': 1,
 \   'callback': 'ale_linters#elixir#dogma#Handle',
 \})
diff --git a/ale_linters/elixir/mix.vim b/ale_linters/elixir/mix.vim
index 4552ace5..dc3c1818 100644
--- a/ale_linters/elixir/mix.vim
+++ b/ale_linters/elixir/mix.vim
@@ -29,18 +29,8 @@ function! ale_linters#elixir#mix#Handle(buffer, lines) abort
     return l:output
 endfunction
 
-function! ale_linters#elixir#mix#FindProjectRoot(buffer) abort
-    let l:mix_file = ale#path#FindNearestFile(a:buffer, 'mix.exs')
-
-    if !empty(l:mix_file)
-      return fnamemodify(l:mix_file, ':p:h')
-    endif
-
-    return '.'
-endfunction
-
 function! ale_linters#elixir#mix#GetCommand(buffer) abort
-    let l:project_root = ale_linters#elixir#mix#FindProjectRoot(a:buffer)
+    let l:project_root = ale#handlers#elixir#FindMixProjectRoot(a:buffer)
 
     let l:temp_dir = ale#engine#CreateDirectory(a:buffer)
 
@@ -49,8 +39,8 @@ function! ale_linters#elixir#mix#GetCommand(buffer) abort
     \   : 'MIX_BUILD_PATH=' . ale#Escape(l:temp_dir)
 
     return ale#path#CdString(l:project_root)
-          \ . l:mix_build_path
-          \ . ' mix compile %s'
+    \ . l:mix_build_path
+    \ . ' mix compile %s'
 endfunction
 
 call ale#linter#Define('elixir', {
diff --git a/autoload/ale/handlers/elixir.vim b/autoload/ale/handlers/elixir.vim
new file mode 100644
index 00000000..91b75aac
--- /dev/null
+++ b/autoload/ale/handlers/elixir.vim
@@ -0,0 +1,13 @@
+" Author: Matteo Centenaro (bugant) - https://github.com/bugant
+"
+" Description: find the root directory for an elixir project that uses mix
+
+function! ale#handlers#elixir#FindMixProjectRoot(buffer) abort
+    let l:mix_file = ale#path#FindNearestFile(a:buffer, 'mix.exs')
+
+    if !empty(l:mix_file)
+      return fnamemodify(l:mix_file, ':p:h')
+    endif
+
+    return '.'
+endfunction
diff --git a/test/command_callback/elixir_paths/mix_project/lib/foo.ex b/test/command_callback/elixir_paths/mix_project/lib/foo.ex
new file mode 100644
index 00000000..e69de29b
--- /dev/null
+++ b/test/command_callback/elixir_paths/mix_project/lib/foo.ex
diff --git a/test/command_callback/elixir_paths/mix_project/mix.exs b/test/command_callback/elixir_paths/mix_project/mix.exs
new file mode 100644
index 00000000..419685ae
--- /dev/null
+++ b/test/command_callback/elixir_paths/mix_project/mix.exs
@@ -0,0 +1,3 @@
+defmodule Test.MixProject do
+  # fake mix project file
+end
diff --git a/test/command_callback/test_elixir_mix_command_callbacks.vader b/test/command_callback/test_elixir_mix_command_callbacks.vader
index 18fb13ed..9315a850 100644
--- a/test/command_callback/test_elixir_mix_command_callbacks.vader
+++ b/test/command_callback/test_elixir_mix_command_callbacks.vader
@@ -17,3 +17,10 @@ Execute(The default mix command should be correct):
   \ ale#path#CdString(ale#path#Simplify(g:dir . '/mix_paths/wrapped_project'))
   \ . g:env_prefix
   \ . 'mix compile %s'
+
+Execute(The FindMixProjectRoot should detect the project root directory via mix.exs):                                                  
+  silent execute 'file ' . fnameescape(g:dir . '/elixir_paths/mix_project/lib/app.ex')                                               
+
+  AssertEqual                                                                  
+  \ ale#path#Simplify(g:dir . '/elixir_paths/mix_project'),     
+  \ ale#handlers#elixir#FindMixProjectRoot(bufnr(''))