[clang-tools-extra] 164ed7b - [clangd] Enable some nice clang-tidy checks by default.

[Sam McCall via cfe-commits]

Author: Sam McCall
Date: 2020-04-03T15:40:07+02:00
New Revision: 164ed7b1d0446400123189c9cd168df5448e4233

URL: https://github.com/llvm/llvm-project/commit/164ed7b1d0446400123189c9cd168df5448e4233
DIFF: https://github.com/llvm/llvm-project/commit/164ed7b1d0446400123189c9cd168df5448e4233.diff

LOG: [clangd] Enable some nice clang-tidy checks by default.

Reviewers: hokein

Subscribers: ilya-biryukov, MaskRay, jkorous, arphaman, kadircet, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D77348

Added: 
    

Modified: 
    clang-tools-extra/clangd/tool/ClangdMain.cpp

Removed: 
    


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diff  --git a/clang-tools-extra/clangd/tool/ClangdMain.cpp b/clang-tools-extra/clangd/tool/ClangdMain.cpp
index 9bfc58b55f71..4b3b565ac2b6 100644
--- a/clang-tools-extra/clangd/tool/ClangdMain.cpp
+++ b/clang-tools-extra/clangd/tool/ClangdMain.cpp
@@ -691,18 +691,42 @@ clangd accepts flags on the commandline, and in the CLANGD_FLAGS environment var
   std::unique_ptr<tidy::ClangTidyOptionsProvider>
       ClangTidyOptProvider; /*GUARDED_BY(ClangTidyOptMu)*/
   if (EnableClangTidy) {
-    auto OverrideClangTidyOptions = tidy::ClangTidyOptions::getDefaults();
-    OverrideClangTidyOptions.Checks = ClangTidyChecks;
+    auto EmptyDefaults = tidy::ClangTidyOptions::getDefaults();
+    EmptyDefaults.Checks.reset(); // So we can tell if checks were ever set.
+    tidy::ClangTidyOptions OverrideClangTidyOptions;
+    if (!ClangTidyChecks.empty())
+      OverrideClangTidyOptions.Checks = ClangTidyChecks;
     ClangTidyOptProvider = std::make_unique<tidy::FileOptionsProvider>(
         tidy::ClangTidyGlobalOptions(),
-        /* Default */ tidy::ClangTidyOptions::getDefaults(),
+        /* Default */ EmptyDefaults,
         /* Override */ OverrideClangTidyOptions, FSProvider.getFileSystem());
     Opts.GetClangTidyOptions = [&](llvm::vfs::FileSystem &,
                                    llvm::StringRef File) {
       // This function must be thread-safe and tidy option providers are not.
-      std::lock_guard<std::mutex> Lock(ClangTidyOptMu);
-      // FIXME: use the FS provided to the function.
-      return ClangTidyOptProvider->getOptions(File);
+      tidy::ClangTidyOptions Opts;
+      {
+        std::lock_guard<std::mutex> Lock(ClangTidyOptMu);
+        // FIXME: use the FS provided to the function.
+        Opts = ClangTidyOptProvider->getOptions(File);
+      }
+      if (!Opts.Checks) {
+        // If the user hasn't configured clang-tidy checks at all, including
+        // via .clang-tidy, give them a nice set of checks.
+        // (This should be what the "default" options does, but it isn't...)
+        //
+        // These default checks are chosen for:
+        //  - low false-positive rate
+        //  - providing a lot of value
+        //  - being reasonably efficient
+        Opts.Checks = llvm::join_items(
+            ",", "readability-misleading-indentation",
+            "readability-deleted-default", "bugprone-integer-division",
+            "bugprone-sizeof-expression", "bugprone-suspicious-missing-comma",
+            "bugprone-unused-raii", "bugprone-unused-return-value",
+            "misc-unused-using-decls", "misc-unused-alias-decls",
+            "misc-definitions-in-headers");
+      }
+      return Opts;
     };
   }
   Opts.SuggestMissingIncludes = SuggestMissingIncludes;