Added builddir option to clang-tidy to point to json folder (#688)

Detect compille_commands.json files for clang-tidy

ale_linters/cpp/clangtidy.vim

@@ -1,4 +1,5 @@
-" Author: vdeurzen <tim@kompiler.org>, w0rp <devw0rp@gmail.com>
+" Author: vdeurzen <tim@kompiler.org>, w0rp <devw0rp@gmail.com>,
+" gagbo <gagbobada@gmail.com>
 " Description: clang-tidy linter for cpp files
 
 " Set this option to check the checks clang-tidy will apply.
@@ -8,15 +9,36 @@ let g:ale_cpp_clangtidy_checks = get(g:, 'ale_cpp_clangtidy_checks', ['*'])
 " This will disable compile_commands.json detection.
 let g:ale_cpp_clangtidy_options = get(g:, 'ale_cpp_clangtidy_options', '')
 
+" Set this option to manually point to the build directory for clang-tidy.
+" This will disable all the other clangtidy_options, since compilation
+" flags are contained in the json
+let g:ale_c_build_dir = get(g:, 'ale_c_build_dir', '')
+
+
 function! ale_linters#cpp#clangtidy#GetCommand(buffer) abort
     let l:check_list = ale#Var(a:buffer, 'cpp_clangtidy_checks')
     let l:check_option = !empty(l:check_list)
     \   ? '-checks=' . ale#Escape(join(l:check_list, ',')) . ' '
     \   : ''
     let l:user_options = ale#Var(a:buffer, 'cpp_clangtidy_options')
+    let l:user_build_dir = ale#Var(a:buffer, 'c_build_dir')
+
+    " c_build_dir has the priority if defined
+    if empty(l:user_build_dir)
+        let l:user_build_dir = ale#c#FindCompileCommands(a:buffer)
+    endif
+
+    " We check again if user_builddir stayed empty after the
+    " c_build_dir_names check
+    " If we found the compilation database we override the value of
+    " l:extra_options
+    if empty(l:user_build_dir)
         let l:extra_options = !empty(l:user_options)
         \   ? ' -- ' . l:user_options
         \   : ''
+    else
+        let l:extra_options = ' -p ' . ale#Escape(l:user_build_dir)
+    endif
 
     return 'clang-tidy ' . l:check_option . '%s' . l:extra_options
 endfunction

autoload/ale/c.vim

@@ -0,0 +1,24 @@
+" Author: gagbo <gagbobada@gmail.com>
+" Description: Functions for integrating with C-family linters.
+
+
+let g:ale_c_build_dir_names = get(g:, 'ale_c_build_dir_names', [
+\   'build',
+\   'bin',
+\])
+
+" Given a buffer number, find the build subdirectory with compile commands
+" The subdirectory is returned without the trailing /
+function! ale#c#FindCompileCommands(buffer) abort
+    for l:path in ale#path#Upwards(expand('#' . a:buffer . ':p:h'))
+        for l:dirname in ale#Var(a:buffer, 'c_build_dir_names')
+            let l:c_build_dir = l:path . '/' . l:dirname
+
+            if filereadable(l:c_build_dir . '/compile_commands.json')
+                return l:c_build_dir
+            endif
+        endfor
+    endfor
+
+    return ''
+endfunction

doc/ale-cpp.txt

@@ -2,6 +2,37 @@
 ALE C++ Integration                                           *ale-cpp-options*
 
 
+-------------------------------------------------------------------------------
+Global Options
+
+g:ale_c_build_dir_names                               *g:ale_c_build_dir_names*
+                                                      *b:ale_c_build_dir_names*
+
+  Type: |List|
+  Default: `['build', 'bin']`
+
+  A list of directory names to be used when searching upwards from cpp
+  files to discover compilation databases with. For directory named `'foo'`,
+  ALE will search for `'foo/compile_commands.json'` in all directories on and above
+  the directory containing the cpp file to find path to compilation database.
+  This feature is useful for the clang tools wrapped around LibTooling (namely
+  here, clang-tidy)
+
+
+g:ale_c_build_dir                                           *g:ale_c_build_dir*
+                                                            *b:ale_c_build_dir*
+
+  Type: |String|
+  Default: `''`
+
+  A path to the directory containing the `compile_commands.json` file to use
+  with c-family linters. Usually setting this option to a non-empty string
+  will override the |g:ale_c_build_dir_names| option to impose a compilation
+  database (it can be useful if multiple builds are in multiple build
+  subdirectories in the project tree).
+  This feature is also most useful for the clang tools linters, wrapped
+  aroung LibTooling (namely clang-tidy here)
+
 -------------------------------------------------------------------------------
 clang                                                           *ale-cpp-clang*
 
@@ -19,6 +50,9 @@ clangtidy                                                   *ale-cpp-clangtidy*
 `clang-tidy` will be run only when files are saved to disk, so that
 `compile_commands.json` files can be used. It is recommended to use this
 linter in combination with `compile_commands.json` files.
+Therefore, `clang-tidy` linter reads the options |g:ale_c_build_dir| and
+|g:ale_c_build_dir_names|. Also, setting |g:ale_c_build_dir| actually
+overrides |g:ale_c_build_dir_names|.
 
 
 g:ale_cpp_clangtidy_checks                         *g:ale_cpp_clangtidy_checks*
@@ -32,7 +66,6 @@ g:ale_cpp_clangtidy_checks                         *g:ale_cpp_clangtidy_checks*
   the shell. The `-checks` flag can be removed entirely by setting this
   option to an empty List.
 
-
 g:ale_cpp_clangtidy_options                       *g:ale_cpp_clangtidy_options*
                                                   *b:ale_cpp_clangtidy_options*
   Type: |String|

test/test_c_import_paths.vader

@@ -226,3 +226,18 @@ Execute(The C++ Clang handler should include root directories for projects with
   \   . ' -I' . ale#Escape(g:dir .  '/test_c_projects/hpp_file_project') . ' '
   \   . ' -'
   \ , 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
+
+  cd test_c_projects/json_project/subdir
+  silent noautocmd file file.cpp
+
+  " TODO Test to move to C-family tools tests
+  " AssertEqual
+  " \   '/testplugin/test/test_c_projects/json_project/build'
+  " \ , ale#c#FindCompileCommands(bufnr(''))
+
+  AssertEqual
+  \   'clang-tidy -checks=''*'' %s -p ''/testplugin/test/test_c_projects/json_project/build'''
+  \ , ale_linters#cpp#clangtidy#GetCommand(bufnr(''))