Upgrade Elm linter to support 0.19 error reports

1 files changed, 78 insertions, 37 deletions

diff --git a/ale_linters/elm/make.vim b/ale_linters/elm/make.vim
index a665cef4..a85e55c4 100644
--- a/ale_linters/elm/make.vim
+++ b/ale_linters/elm/make.vim
@@ -1,46 +1,66 @@
 " Author: buffalocoder - https://github.com/buffalocoder, soywod - https://github.com/soywod
 " Description: Elm linting in Ale. Closely follows the Syntastic checker in https://github.com/ElmCast/elm-vim.
 
-call ale#Set('elm_make_executable', 'elm-make')
-call ale#Set('elm_make_use_global', get(g:, 'ale_use_global_executables', 0))
+call ale#Set('elm_executable', 'elm')
+call ale#Set('elm_use_global', get(g:, 'ale_use_global_executables', 0))
 
 function! ale_linters#elm#make#GetExecutable(buffer) abort
-    return ale#node#FindExecutable(a:buffer, 'elm_make', [
-    \   'node_modules/.bin/elm-make',
+    return ale#node#FindExecutable(a:buffer, 'elm', [
+    \   'node_modules/.bin/elm',
     \])
 endfunction
 
 function! ale_linters#elm#make#Handle(buffer, lines) abort
     let l:output = []
-    let l:is_windows = has('win32')
-    let l:temp_dir = l:is_windows ? $TMP : $TMPDIR
     let l:unparsed_lines = []
+
     for l:line in a:lines
-        if l:line[0] is# '['
-            let l:errors = json_decode(l:line)
-
-            for l:error in l:errors
-                " Check if file is from the temp directory.
-                " Filters out any errors not related to the buffer.
-                if l:is_windows
-                    let l:file_is_buffer = l:error.file[0:len(l:temp_dir) - 1] is? l:temp_dir
-                else
-                    let l:file_is_buffer = l:error.file[0:len(l:temp_dir) - 1] is# l:temp_dir
-                endif
-
-                if l:file_is_buffer
-                    call add(l:output, {
-                    \    'lnum': l:error.region.start.line,
-                    \    'col': l:error.region.start.column,
-                    \    'end_lnum': l:error.region.end.line,
-                    \    'end_col': l:error.region.end.column,
-                    \    'type': (l:error.type is? 'error') ? 'E' : 'W',
-                    \    'text': l:error.overview,
-                    \    'detail': l:error.overview . "\n\n" . l:error.details
-                    \})
-                endif
-            endfor
-        elseif l:line isnot# 'Successfully generated /dev/null'
+        if l:line[0] is# '{'
+            let l:report = json_decode(l:line)
+
+            if l:report.type is? 'error'
+                " General problem
+                let l:details = map(copy(l:report.message), 'ale_linters#elm#make#ParseMessageItem(v:val)')
+
+                call add(l:output, {
+                            \    'lnum': 1,
+                            \    'type': 'E',
+                            \    'text': l:report.title,
+                            \    'detail': join(l:details, '')
+                            \})
+            else
+                " Compilation errors
+                for l:error in l:report.errors
+                    let l:file_is_buffer = ale_linters#elm#make#FileIsBuffer(l:error.path)
+
+                    for l:problem in l:error.problems
+                        let l:details = map(copy(l:problem.message), 'ale_linters#elm#make#ParseMessageItem(v:val)')
+
+                        if l:file_is_buffer
+                            " Buffer module has problems
+                            call add(l:output, {
+                                        \    'lnum': l:problem.region.start.line,
+                                        \    'col': l:problem.region.start.column,
+                                        \    'end_lnum': l:problem.region.end.line,
+                                        \    'end_col': l:problem.region.end.column,
+                                        \    'type': 'E',
+                                        \    'text': l:problem.title,
+                                        \    'detail': join(l:details, '')
+                                        \})
+                        else
+                            " Imported module has problems
+                            let l:location = l:error.path .':'. l:problem.region.start.line
+                            call add(l:output, {
+                                        \    'lnum': 1,
+                                        \    'type': 'E',
+                                        \    'text': l:location .' - '. l:problem.title,
+                                        \    'detail':  l:location ." -------\n\n" . join(l:details, '')
+                                        \})
+                        endif
+                    endfor
+                endfor
+            endif
+        else
             call add(l:unparsed_lines, l:line)
         endif
     endfor
@@ -57,23 +77,44 @@ function! ale_linters#elm#make#Handle(buffer, lines) abort
     return l:output
 endfunction
 
+function! ale_linters#elm#make#FileIsBuffer(path) abort
+    let l:is_windows = has('win32')
+    let l:temp_dir = l:is_windows ? $TMP : $TMPDIR
+
+    if has('win32')
+        return a:path[0:len(l:temp_dir) - 1] is? l:temp_dir
+    else
+        return a:path[0:len(l:temp_dir) - 1] is# l:temp_dir
+    endif
+endfunction
+
+function! ale_linters#elm#make#ParseMessageItem(item) abort
+    if type(a:item) == type('')
+        return a:item
+    else
+        return a:item.string
+    endif
+endfunction
+
 " Return the command to execute the linter in the projects directory.
 " If it doesn't, then this will fail when imports are needed.
 function! ale_linters#elm#make#GetCommand(buffer) abort
-    let l:elm_package = ale#path#FindNearestFile(a:buffer, 'elm-package.json')
+    let l:elm_json = ale#path#FindNearestFile(a:buffer, 'elm.json')
     let l:elm_exe = ale_linters#elm#make#GetExecutable(a:buffer)
-    if empty(l:elm_package)
+
+    if empty(l:elm_json)
         let l:dir_set_cmd = ''
     else
-        let l:root_dir = fnamemodify(l:elm_package, ':p:h')
+        let l:root_dir = fnamemodify(l:elm_json, ':p:h')
         let l:dir_set_cmd = 'cd ' . ale#Escape(l:root_dir) . ' && '
     endif
 
-    " The elm-make compiler, at the time of this writing, uses '/dev/null' as
+    " The elm compiler, at the time of this writing, uses '/dev/null' as
     " a sort of flag to tell the compiler not to generate an output file,
-    " which is why this is hard coded here. It does not use NUL on Windows.
-    " Source: https://github.com/elm-lang/elm-make/blob/master/src/Flags.hs
+    " which is why this is hard coded here.
+    " Source: https://github.com/elm-lang/elm-compiler/blob/19d5a769b30ec0b2fc4475985abb4cd94cd1d6c3/builder/src/Generate/Output.hs#L253
     let l:elm_cmd = ale#Escape(l:elm_exe)
+    \   . ' make'
     \   . ' --report=json'
     \   . ' --output=/dev/null'