[clangd] Collect missing macro references.

[hokein]

Summary

Semantic highlghting is missing a few macro references.

[ilya-biryukov]

LGTM

clang-tools-extra/trunk/clangd/CollectMacros.h

 
 struct MainFileMacros {
   llvm::StringSet<> Names;
   // Instead of storing SourceLocation, we have to store the token range because
   // SourceManager from preamble is not available when we build the AST.
   std::vector<Range> Ranges;
 };
 
-/// Collects macro definitions and expansions in the main file. It is used to:
+/// Collects macro references (e.g. definitions, expansions) in the main file.
+/// It is used to:
 ///  - collect macros in the preamble section of the main file (in Preamble.cpp)
 ///  - collect macros after the preamble of the main file (in ParsedAST.cpp)
 class CollectMainFileMacros : public PPCallbacks {
 public:
   explicit CollectMainFileMacros(const SourceManager &SM,
                                  const LangOptions &LangOpts,
                                  MainFileMacros &Out)
       : SM(SM), LangOpts(LangOpts), Out(Out) {}
 
   void FileChanged(SourceLocation Loc, FileChangeReason,
                    SrcMgr::CharacteristicKind, FileID) override {
     InMainFile = isInsideMainFile(Loc, SM);
   }
 
   void MacroDefined(const Token &MacroName, const MacroDirective *MD) override {
     add(MacroName, MD->getMacroInfo());
   }
 
   void MacroExpands(const Token &MacroName, const MacroDefinition &MD,
                     SourceRange Range, const MacroArgs *Args) override {
     add(MacroName, MD.getMacroInfo());
   }
 
+  void MacroUndefined(const clang::Token &MacroName,
+                      const clang::MacroDefinition &MD,
+                      const clang::MacroDirective *Undef) override {
+    add(MacroName, MD.getMacroInfo());
+  }
+
+  void Ifdef(SourceLocation Loc, const Token &MacroName,
+             const MacroDefinition &MD) override {
+    add(MacroName, MD.getMacroInfo());
+  }
+
+  void Ifndef(SourceLocation Loc, const Token &MacroName,
+              const MacroDefinition &MD) override {
+    add(MacroName, MD.getMacroInfo());
+  }
+
+  void Defined(const Token &MacroName, const MacroDefinition &MD,
+               SourceRange Range) override {
+    add(MacroName, MD.getMacroInfo());
+  }
+
 private:
   void add(const Token &MacroNameTok, const MacroInfo *MI) {
     if (!InMainFile)
       return;
     auto Loc = MacroNameTok.getLocation();
     if (Loc.isMacroID())
       return;
 
-    if (auto Range = getTokenRange(SM, LangOpts, MacroNameTok.getLocation())) {
+    if (auto Range = getTokenRange(SM, LangOpts, Loc)) {
       Out.Names.insert(MacroNameTok.getIdentifierInfo()->getName());
       Out.Ranges.push_back(*Range);
     }
   }
   const SourceManager &SM;
   const LangOptions &LangOpts;
   bool InMainFile = true;
   MainFileMacros &Out;
 };
 
 } // namespace clangd
 } // namespace clang
 
 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANGD_COLLECTEDMACROS_H

clang-tools-extra/trunk/clangd/unittests/SemanticHighlightingTests.cpp

)cpp",
       $Primitive[[int]] $Variable[[x]];
       $Primitive[[int]] $Variable[[y]];
       $Primitive[[int]] $Function[[f]]();
       $Primitive[[void]] $Function[[foo]]() {
         $Macro[[assert]]($Variable[[x]] != $Variable[[y]]);
         $Macro[[assert]]($Variable[[x]] != $Function[[f]]());
       }
     )cpp",
+      // highlighting all macro references
+      R"cpp(
+      #ifndef $Macro[[name]]
+      #define $Macro[[name]]
+      #endif
+
+      #define $Macro[[test]]
+      #undef $Macro[[test]]
+      #ifdef $Macro[[test]]
+      #endif
+
+      #if defined($Macro[[test]])
+      #endif
+    )cpp",
       R"cpp(
       struct $Class[[S]] {
         $Primitive[[float]] $Field[[Value]];
         $Class[[S]] *$Field[[Next]];
       };
       $Class[[S]] $Variable[[Global]][2] = {$Class[[S]](), $Class[[S]]()};
       $Primitive[[void]] $Function[[f]]($Class[[S]] $Parameter[[P]]) {
         $Primitive[[int]] $LocalVariable[[A]][2] = {1,2};
EXPECT_THAT(ActualDiff,
               testing::UnorderedElementsAre(
                   testing::AllOf(LineNumber(3), EmptyHighlightings()),
                   testing::AllOf(LineNumber(4), EmptyHighlightings())));
 }
 
 } // namespace
 } // namespace clangd
 } // namespace clang
 No newline at end of file