#392 - Detect and use compile_commands.json for cppcheck

ale_linters/c/cppcheck.vim

@@ -5,7 +5,22 @@
 let g:ale_c_cppcheck_options = get(g:, 'ale_c_cppcheck_options', '--enable=style')
 
 function! ale_linters#c#cppcheck#GetCommand(buffer) abort
-    return 'cppcheck -q --language=c '
+    " Search upwards from the file for compile_commands.json.
+    "
+    " If we find it, we'll `cd` to where the compile_commands.json file is,
+    " then use the file to set up import paths, etc.
+    let l:compile_commmands_path = ale#path#FindNearestFile(a:buffer, 'compile_commands.json')
+
+    let l:cd_command = !empty(l:compile_commmands_path)
+    \   ? ale#path#CdString(fnamemodify(l:compile_commmands_path, ':h'))
+    \   : ''
+    let l:compile_commands_option = !empty(l:compile_commmands_path)
+    \   ? '--project=compile_commands.json '
+    \   : ''
+
+    return l:cd_command
+    \   . 'cppcheck -q --language=c '
+    \   . l:compile_commands_option
     \   . ale#Var(a:buffer, 'c_cppcheck_options')
     \   . ' %t'
 endfunction

ale_linters/cpp/cppcheck.vim

@@ -5,7 +5,22 @@
 let g:ale_cpp_cppcheck_options = get(g:, 'ale_cpp_cppcheck_options', '--enable=style')
 
 function! ale_linters#cpp#cppcheck#GetCommand(buffer) abort
-    return 'cppcheck -q --language=c++ '
+    " Search upwards from the file for compile_commands.json.
+    "
+    " If we find it, we'll `cd` to where the compile_commands.json file is,
+    " then use the file to set up import paths, etc.
+    let l:compile_commmands_path = ale#path#FindNearestFile(a:buffer, 'compile_commands.json')
+
+    let l:cd_command = !empty(l:compile_commmands_path)
+    \   ? ale#path#CdString(fnamemodify(l:compile_commmands_path, ':h'))
+    \   : ''
+    let l:compile_commands_option = !empty(l:compile_commmands_path)
+    \   ? '--project=compile_commands.json '
+    \   : ''
+
+    return l:cd_command
+    \   . 'cppcheck -q --language=c++ '
+    \   . l:compile_commands_option
     \   . ale#Var(a:buffer, 'cpp_cppcheck_options')
     \   . ' %t'
 endfunction

test/command_callback/test_cppcheck_command_callbacks.vader

@@ -0,0 +1,40 @@
+Before:
+  silent! cd /testplugin/test/command_callback
+  let b:dir = getcwd()
+
+After:
+  silent execute 'cd ' . fnameescape(b:dir)
+  unlet! b:dir
+  call ale#linter#Reset()
+
+Execute(The default C cppcheck command should be correct):
+  runtime ale_linters/c/cppcheck.vim
+
+  AssertEqual
+  \ 'cppcheck -q --language=c --enable=style %t',
+  \ ale_linters#c#cppcheck#GetCommand(bufnr(''))
+
+Execute(cppcheck for C should detect compile_commands.json files):
+  runtime ale_linters/c/cppcheck.vim
+  cd cppcheck_paths/one
+
+  AssertEqual
+  \ 'cd ' . fnameescape(b:dir . '/cppcheck_paths/one') . ' && '
+  \ . 'cppcheck -q --language=c --project=compile_commands.json --enable=style %t',
+  \ ale_linters#c#cppcheck#GetCommand(bufnr(''))
+
+Execute(The default C++ cppcheck command should be correct):
+  runtime ale_linters/cpp/cppcheck.vim
+
+  AssertEqual
+  \ 'cppcheck -q --language=c++ --enable=style %t',
+  \ ale_linters#cpp#cppcheck#GetCommand(bufnr(''))
+
+Execute(cppcheck for C++ should detect compile_commands.json files):
+  runtime ale_linters/cpp/cppcheck.vim
+  cd cppcheck_paths/one
+
+  AssertEqual
+  \ 'cd ' . fnameescape(b:dir . '/cppcheck_paths/one') . ' && '
+  \ . 'cppcheck -q --language=c++ --project=compile_commands.json --enable=style %t',
+  \ ale_linters#cpp#cppcheck#GetCommand(bufnr(''))