Merge pull request #2241 from bk2204/lsp-detect-hook

Add a hook to detect LSP project root

autoload/ale/assert.vim

@@ -109,6 +109,14 @@ function! ale#assert#LSPProject(expected_root) abort
     AssertEqual a:expected_root, l:root
 endfunction
 
+function! ale#assert#LSPProjectFull(expected_root) abort
+    let l:buffer = bufnr('')
+    let l:linter = s:GetLinter()
+    let l:root = ale#lsp_linter#FindProjectRoot(l:buffer, l:linter)
+
+    AssertEqual a:expected_root, l:root
+endfunction
+
 function! ale#assert#LSPAddress(expected_address) abort
     let l:buffer = bufnr('')
     let l:linter = s:GetLinter()
@@ -158,6 +166,7 @@ function! ale#assert#SetUpLinterTest(filetype, name) abort
     command! -nargs=+ AssertLSPConfig :call ale#assert#LSPConfig(<args>)
     command! -nargs=+ AssertLSPLanguage :call ale#assert#LSPLanguage(<args>)
     command! -nargs=+ AssertLSPProject :call ale#assert#LSPProject(<args>)
+    command! -nargs=+ AssertLSPProjectFull :call ale#assert#LSPProjectFull(<args>)
     command! -nargs=+ AssertLSPAddress :call ale#assert#LSPAddress(<args>)
 endfunction
 
@@ -193,6 +202,10 @@ function! ale#assert#TearDownLinterTest() abort
         delcommand AssertLSPProject
     endif
 
+    if exists(':AssertLSPProjectFull')
+        delcommand AssertLSPProjectFull
+    endif
+
     if exists(':AssertLSPAddress')
         delcommand AssertLSPAddress
     endif

autoload/ale/debugging.vim

@@ -31,6 +31,7 @@ let s:global_variable_list = [
 \    'ale_list_vertical',
 \    'ale_list_window_size',
 \    'ale_loclist_msg_format',
+\    'ale_lsp_root',
 \    'ale_max_buffer_history_size',
 \    'ale_max_signs',
 \    'ale_maximum_file_size',

autoload/ale/lsp_linter.vim

@@ -152,12 +152,45 @@ function! ale#lsp_linter#GetConfig(buffer, linter) abort
     return l:config
 endfunction
 
+function! ale#lsp_linter#FindProjectRoot(buffer, linter) abort
+    let l:buffer_ale_root = getbufvar(a:buffer, 'ale_lsp_root', {})
+
+    if type(l:buffer_ale_root) is v:t_string
+        return l:buffer_ale_root
+    endif
+
+    " Try to get a buffer-local setting for the root
+    if has_key(l:buffer_ale_root, a:linter.name)
+        let l:Root = l:buffer_ale_root[a:linter.name]
+
+        if type(l:Root) is v:t_func
+            return l:Root(a:buffer)
+        else
+            return l:Root
+        endif
+    endif
+
+    " Try to get a global setting for the root
+    if has_key(g:ale_lsp_root, a:linter.name)
+        let l:Root = g:ale_lsp_root[a:linter.name]
+
+        if type(l:Root) is v:t_func
+            return l:Root(a:buffer)
+        else
+            return l:Root
+        endif
+    endif
+
+    " Fall back to the linter-specific configuration
+    return ale#util#GetFunction(a:linter.project_root_callback)(a:buffer)
+endfunction
+
 " 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)
+    let l:root = ale#lsp_linter#FindProjectRoot(a:buffer, a:linter)
 
     if empty(l:root) && a:linter.lsp isnot# 'tsserver'
         " If there's no project root, then we can't check files with LSP,

doc/ale.txt

@@ -1572,6 +1572,22 @@ b:ale_loclist_msg_format                             *b:ale_loclist_msg_format*
 
   The strings for configuring `%severity%` are also used for this option.
 
+g:ale_lsp_root                                                 *g:ale_lsp_root*
+b:ale_lsp_root                                                 *b:ale_lsp_root*
+
+  Type: |Dictionary| or |String|
+  Default: {}
+
+  This option is used to determine the project root for the LSP linter. If the
+  value is a |Dictionary|, it maps a linter to either a string containing the
+  project root or a |Funcref| to call to look up the root. The funcref is
+  provided the buffer number as its argument.
+
+  The buffer-specific variable may additionally be a string containing the
+  project root itself.
+
+  If neither variable yields a result, a linter-specific function is invoked to
+  detect a project root. If this, too, yields no result, the linter is disabled.
 
 g:ale_max_buffer_history_size                   *g:ale_max_buffer_history_size*
 

plugin/ale.vim

@@ -87,6 +87,9 @@ let g:ale_lint_on_save = get(g:, 'ale_lint_on_save', 1)
 " This flag can be set to 1 to enable linting when the filetype is changed.
 let g:ale_lint_on_filetype_changed = get(g:, 'ale_lint_on_filetype_changed', 1)
 
+" This Dictionary configures the default LSP roots for various linters.
+let g:ale_lsp_root = get(g:, 'ale_lsp_root', {})
+
 " This flag can be set to 1 to enable automatically fixing files on save.
 let g:ale_fix_on_save = get(g:, 'ale_fix_on_save', 0)
 

test/lsp/test_lsp_command_formatting.vader

@@ -17,6 +17,7 @@ Execute(Command formatting should be applied correctly for LSP linters):
   call ale#lsp_linter#StartLSP(
   \ bufnr(''),
   \ {
+  \   'name': 'linter',
   \   'language_callback': {-> 'x'},
   \   'project_root_callback': {-> '/foo/bar'},
   \   'lsp': 'stdio',

test/lsp/test_lsp_root_detection.vader

@@ -0,0 +1,63 @@
+Before:
+  call ale#assert#SetUpLinterTest('c', 'clangd')
+
+  function! Hook1(buffer)
+    return 'abc123'
+  endfunction
+
+After:
+  let g:ale_lsp_root = {}
+  unlet! b:ale_lsp_root
+  delfunction Hook1
+
+  call ale#assert#TearDownLinterTest()
+
+Execute(The buffer-specific variable can be a string):
+  let b:ale_lsp_root = '/some/path'
+  call ale#test#SetFilename('other-file.c')
+
+  AssertLSPProjectFull '/some/path'
+
+Execute(The buffer-specific variable can be a dictionary):
+  let b:ale_lsp_root = {'clangd': '/some/path', 'golangserver': '/other/path'}
+  call ale#test#SetFilename('other-file.c')
+
+  AssertLSPProjectFull '/some/path'
+
+Execute(The buffer-specific variable can have funcrefs):
+  let b:ale_lsp_root = {'clangd': function('Hook1'), 'golangserver': '/path'}
+  call ale#test#SetFilename('other-file.c')
+
+  AssertLSPProjectFull 'abc123'
+
+Execute(The global variable can be a dictionary):
+  let g:ale_lsp_root = {'clangd': '/some/path', 'golangserver': '/other/path'}
+  call ale#test#SetFilename('other-file.c')
+
+  AssertLSPProjectFull '/some/path'
+
+Execute(The global variable can have funcrefs):
+  let g:ale_lsp_root = {'clangd': function('Hook1'), 'golangserver': '/path'}
+  call ale#test#SetFilename('other-file.c')
+
+  AssertLSPProjectFull 'abc123'
+
+Execute(The buffer-specific variable overrides the global variable):
+  let b:ale_lsp_root = {'clangd': '/some/path', 'golangserver': '/other/path'}
+  let g:ale_lsp_root = {'clangd': '/not/this/path', 'golangserver': '/elsewhere'}
+  call ale#test#SetFilename('other-file.c')
+
+  AssertLSPProjectFull '/some/path'
+
+Execute(The global variable is queried if the buffer-specific has no value):
+  let b:ale_lsp_root = {'golangserver': '/other/path'}
+  let g:ale_lsp_root = {'clangd': '/some/path', 'golangserver': '/elsewhere'}
+  call ale#test#SetFilename('other-file.c')
+
+  AssertLSPProjectFull '/some/path'
+
+
+Execute(The default hook value is acceptable):
+  call ale#test#SetFilename('other-file.c')
+
+  AssertLSPProjectFull ''

test/test_ale_info.vader

@@ -97,6 +97,7 @@ Before:
   \  'let g:ale_list_vertical = 0',
   \  'let g:ale_list_window_size = 10',
   \  'let g:ale_loclist_msg_format = ''%code: %%s''',
+  \  'let g:ale_lsp_root = {}',
   \  'let g:ale_max_buffer_history_size = 20',
   \  'let g:ale_max_signs = -1',
   \  'let g:ale_maximum_file_size = 0',