[clangd] No longer getting template instantiations from header files in Main AST.

[jvikstrom]

Summary

[clangd] No longer getting template instantiations from header files in Main AST. Added another check to DeclTrackingASTConsumer to check that a Decl is actually in the main file.

[hokein]

clang-tools-extra/clangd/ClangdUnit.cpp

74

you could get SourceManager from D->getASTContext().getSourceManager().

75

nit: This comment just repeats the code, I think the comment describe why we need to do this check (because of the template instantiation?)

[jvikstrom]

Removed comment, getting SM from Decl and removed old check for checking the file.

[jvikstrom]

clang-tools-extra/clangd/ClangdUnit.cpp

75

Removed the D->isFromASTFile because this if actually covers that as well. Don't know what to do about comments though as it is not only specific to that case.

[ilya-biryukov]

clang-tools-extra/clangd/ClangdUnit.cpp

47

NIT: This include is redundant, maybe remove?
Probably added by accident.

71

Please use isWrittenInMainFile instead.
isInMainFile takes #line markers into account, we don't want that in clangd.

[jvikstrom]

Using isInMainFile instead

[jvikstrom]

Fixed formatting

[hokein]

Looks good, please update the patch description (in git, and phabricator), mentioning why the previous solution won't work.

clang-tools-extra/clangd/ClangdUnit.cpp

72

nit: remove the {}

clang-tools-extra/clangd/ClangdUnit.cpp

 #include "clang/Tooling/Syntax/Tokens.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/Support/raw_ostream.h"
 #include <algorithm>
 #include <memory>
+#include <iostream>
 
 namespace clang {
 namespace clangd {
 namespace {
 
 bool compileCommandsAreEqual(const tooling::CompileCommand &LHS,
                              const tooling::CompileCommand &RHS) {
   // We don't check for Output, it should not matter to clangd.
   return LHS.Directory == RHS.Directory && LHS.Filename == RHS.Filename &&
          llvm::makeArrayRef(LHS.CommandLine).equals(RHS.CommandLine);
 }
 
 template <class T> std::size_t getUsedBytes(const std::vector<T> &Vec) {
   return Vec.capacity() * sizeof(T);
 }
 
 class DeclTrackingASTConsumer : public ASTConsumer {
 public:
   DeclTrackingASTConsumer(std::vector<Decl *> &TopLevelDecls)
       : TopLevelDecls(TopLevelDecls) {}
 
   bool HandleTopLevelDecl(DeclGroupRef DG) override {
     for (Decl *D : DG) {
-      if (D->isFromASTFile())
+      if (!D->getASTContext().getSourceManager().isInMainFile(D->getLocation()))
         continue;
 
       // ObjCMethodDecl are not actually top-level decls.
       if (isa<ObjCMethodDecl>(D))
         continue;
 
       TopLevelDecls.push_back(D);
     }
     return true;
   }
 
 private:

clang-tools-extra/clangd/unittests/ClangdUnitTests.cpp

TU.HeaderCode = R"(
     int header1();
     int header2;
   )";
   TU.Code = "int main();";
   auto AST = TU.build();
   EXPECT_THAT(AST.getLocalTopLevelDecls(), ElementsAre(DeclNamed("main")));
 }
 
+TEST(ClangdUnitTest, DoesNotGetIncludedTopDecls) {
+  TestTU TU;
+  TU.HeaderCode = R"cpp(
+    template<class T>
+    struct H {
+      H() {}
+    };
+  )cpp";
+  TU.Code = R"cpp(
+    int main() {
+      H<int> h;
+    }
+  )cpp";
+  auto AST = TU.build();
+  EXPECT_THAT(AST.getLocalTopLevelDecls(), ElementsAre(DeclNamed("main")));
+}
+
 TEST(ClangdUnitTest, TokensAfterPreamble) {
   TestTU TU;
   TU.AdditionalFiles["foo.h"] = R"(
     int foo();
   )";
   TU.Code = R"cpp(
       #include "foo.h"
       first_token;