[clang-tools-extra] r340004 - [clangd] Show function documentation in signature help

[Ilya Biryukov via cfe-commits]

Author: ibiryukov
Date: Fri Aug 17 02:29:38 2018
New Revision: 340004

URL: http://llvm.org/viewvc/llvm-project?rev=340004&view=rev
Log:
[clangd] Show function documentation in signature help

Summary:
Previously, clangd was trying to show documentation for the active
parameter instead, which is wrong per LSP specification.

Moreover, the code path that attempts to get parameter comments never
succeds, because no attempt is made to parse function doc comment and
extract parameter-specific parts out of it. So we also remove the code
that claims to fetch parameter comments: it is not used anymore and is
incorrect.

Reviewers: hokein, ioeric, kadircet

Reviewed By: ioeric

Subscribers: MaskRay, jkorous, arphaman, cfe-commits

Differential Revision: https://reviews.llvm.org/D50726

Modified:
    clang-tools-extra/trunk/clangd/CodeComplete.cpp
    clang-tools-extra/trunk/clangd/CodeCompletionStrings.cpp
    clang-tools-extra/trunk/clangd/CodeCompletionStrings.h

Modified: clang-tools-extra/trunk/clangd/CodeComplete.cpp
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clangd/CodeComplete.cpp?rev=340004&r1=340003&r2=340004&view=diff
==============================================================================
--- clang-tools-extra/trunk/clangd/CodeComplete.cpp (original)
+++ clang-tools-extra/trunk/clangd/CodeComplete.cpp Fri Aug 17 02:29:38 2018
@@ -729,8 +729,9 @@ public:
       // FIXME: for headers, we need to get a comment from the index.
       ScoredSignatures.push_back(processOverloadCandidate(
           Candidate, *CCS,
-          getParameterDocComment(S.getASTContext(), Candidate, CurrentArg,
-                                 /*CommentsFromHeaders=*/false)));
+          Candidate.getFunction()
+              ? getDeclComment(S.getASTContext(), *Candidate.getFunction())
+              : ""));
     }
     std::sort(ScoredSignatures.begin(), ScoredSignatures.end(),
               [](const ScoredSignature &L, const ScoredSignature &R) {

Modified: clang-tools-extra/trunk/clangd/CodeCompletionStrings.cpp
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clangd/CodeCompletionStrings.cpp?rev=340004&r1=340003&r2=340004&view=diff
==============================================================================
--- clang-tools-extra/trunk/clangd/CodeCompletionStrings.cpp (original)
+++ clang-tools-extra/trunk/clangd/CodeCompletionStrings.cpp Fri Aug 17 02:29:38 2018
@@ -51,44 +51,26 @@ std::string getDocComment(const ASTConte
   // get this declaration, so we don't show documentation in that case.
   if (Result.Kind != CodeCompletionResult::RK_Declaration)
     return "";
-  auto *Decl = Result.getDeclaration();
-  if (!Decl || llvm::isa<NamespaceDecl>(Decl)) {
+  return Result.getDeclaration() ? getDeclComment(Ctx, *Result.getDeclaration())
+                                 : "";
+}
+
+std::string getDeclComment(const ASTContext &Ctx, const NamedDecl &Decl) {
+  if (llvm::isa<NamespaceDecl>(Decl)) {
     // Namespaces often have too many redecls for any particular redecl comment
     // to be useful. Moreover, we often confuse file headers or generated
     // comments with namespace comments. Therefore we choose to just ignore
     // the comments for namespaces.
     return "";
   }
-  const RawComment *RC = getCompletionComment(Ctx, Decl);
-  if (!RC)
-    return "";
-
-  // Sanity check that the comment does not come from the PCH. We choose to not
-  // write them into PCH, because they are racy and slow to load.
-  assert(!Ctx.getSourceManager().isLoadedSourceLocation(RC->getBeginLoc()));
-  std::string Doc = RC->getFormattedText(Ctx.getSourceManager(), Ctx.getDiagnostics());
-  if (!looksLikeDocComment(Doc))
-    return "";
-  return Doc;
-}
-
-std::string
-getParameterDocComment(const ASTContext &Ctx,
-                       const CodeCompleteConsumer::OverloadCandidate &Result,
-                       unsigned ArgIndex, bool CommentsFromHeaders) {
-  auto *Func = Result.getFunction();
-  if (!Func)
-    return "";
-  const RawComment *RC = getParameterComment(Ctx, Result, ArgIndex);
+  const RawComment *RC = getCompletionComment(Ctx, &Decl);
   if (!RC)
     return "";
   // Sanity check that the comment does not come from the PCH. We choose to not
   // write them into PCH, because they are racy and slow to load.
   assert(!Ctx.getSourceManager().isLoadedSourceLocation(RC->getBeginLoc()));
   std::string Doc = RC->getFormattedText(Ctx.getSourceManager(), Ctx.getDiagnostics());
-  if (!looksLikeDocComment(Doc))
-    return "";
-  return Doc;
+  return looksLikeDocComment(Doc) ? Doc : "";
 }
 
 void getSignature(const CodeCompletionString &CCS, std::string *Signature,

Modified: clang-tools-extra/trunk/clangd/CodeCompletionStrings.h
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clangd/CodeCompletionStrings.h?rev=340004&r1=340003&r2=340004&view=diff
==============================================================================
--- clang-tools-extra/trunk/clangd/CodeCompletionStrings.h (original)
+++ clang-tools-extra/trunk/clangd/CodeCompletionStrings.h Fri Aug 17 02:29:38 2018
@@ -33,18 +33,8 @@ std::string getDocComment(const ASTConte
                           const CodeCompletionResult &Result,
                           bool CommentsFromHeaders);
 
-/// Gets a minimally formatted documentation for parameter of \p Result,
-/// corresponding to argument number \p ArgIndex.
-/// This currently looks for comments attached to the parameter itself, and
-/// doesn't extract them from function documentation.
-/// Returns empty string when no comment is available.
-/// If \p CommentsFromHeaders parameter is set, only comments from the main
-/// file will be returned. It is used to workaround crashes when parsing
-/// comments in the stale headers, coming from completion preamble.
-std::string
-getParameterDocComment(const ASTContext &Ctx,
-                       const CodeCompleteConsumer::OverloadCandidate &Result,
-                       unsigned ArgIndex, bool CommentsFromHeaders);
+/// Similar to getDocComment, but returns the comment for a NamedDecl.
+std::string getDeclComment(const ASTContext &Ctx, const NamedDecl &D);
 
 /// Formats the signature for an item, as a display string and snippet.
 /// e.g. for const_reference std::vector<T>::at(size_type) const, this returns: