diff --git a/clang-tools-extra/clangd/CodeComplete.cpp b/clang-tools-extra/clangd/CodeComplete.cpp --- a/clang-tools-extra/clangd/CodeComplete.cpp +++ b/clang-tools-extra/clangd/CodeComplete.cpp @@ -394,8 +394,9 @@ Bundled.emplace_back(); BundledEntry &S = Bundled.back(); if (C.SemaResult) { + bool IsPattern = C.SemaResult->Kind == CodeCompletionResult::RK_Pattern; getSignature(*SemaCCS, &S.Signature, &S.SnippetSuffix, - &Completion.RequiredQualifier); + &Completion.RequiredQualifier, IsPattern); S.ReturnType = getReturnType(*SemaCCS); } else if (C.IndexResult) { S.Signature = C.IndexResult->Signature; diff --git a/clang-tools-extra/clangd/CodeCompletionStrings.h b/clang-tools-extra/clangd/CodeCompletionStrings.h --- a/clang-tools-extra/clangd/CodeCompletionStrings.h +++ b/clang-tools-extra/clangd/CodeCompletionStrings.h @@ -38,12 +38,15 @@ /// Formats the signature for an item, as a display string and snippet. /// e.g. for const_reference std::vector::at(size_type) const, this returns: /// *Signature = "(size_type) const" -/// *Snippet = "(${0:size_type})" +/// *Snippet = "(${1:size_type})" /// If set, RequiredQualifiers is the text that must be typed before the name. /// e.g "Base::" when calling a base class member function that's hidden. +/// When \p CompletingPattern is true, the last placeholder will be of the form +/// ${0:…}, indicating the cursor should stay there. void getSignature(const CodeCompletionString &CCS, std::string *Signature, std::string *Snippet, - std::string *RequiredQualifiers = nullptr); + std::string *RequiredQualifiers = nullptr, + bool CompletingPattern = false); /// Assembles formatted documentation for a completion result. This includes /// documentation comments and other relevant information like annotations. diff --git a/clang-tools-extra/clangd/CodeCompletionStrings.cpp b/clang-tools-extra/clangd/CodeCompletionStrings.cpp --- a/clang-tools-extra/clangd/CodeCompletionStrings.cpp +++ b/clang-tools-extra/clangd/CodeCompletionStrings.cpp @@ -11,6 +11,8 @@ #include "clang/AST/DeclObjC.h" #include "clang/AST/RawCommentList.h" #include "clang/Basic/SourceManager.h" +#include "clang/Sema/CodeCompleteConsumer.h" +#include #include namespace clang { @@ -73,8 +75,23 @@ } void getSignature(const CodeCompletionString &CCS, std::string *Signature, - std::string *Snippet, std::string *RequiredQualifiers) { - unsigned ArgCount = 0; + std::string *Snippet, std::string *RequiredQualifiers, + bool CompletingPattern) { + // Placeholder with this index will be ${0:…} to mark final cursor position. + // Usually we do not add $0, so the cursor is placed at end of completed text. + unsigned CursorSnippetArg = std::numeric_limits::max(); + if (CompletingPattern) { + // In patterns, it's best to place the cursor at the last placeholder, to + // handle cases like + // namespace ${1:name} { + // ${0:decls} + // } + CursorSnippetArg = + llvm::count_if(CCS, [](const CodeCompletionString::Chunk &C) { + return C.Kind == CodeCompletionString::CK_Placeholder; + }); + } + unsigned SnippetArg = 0; bool HadObjCArguments = false; for (const auto &Chunk : CCS) { // Informative qualifier chunks only clutter completion results, skip @@ -124,8 +141,10 @@ break; case CodeCompletionString::CK_Placeholder: *Signature += Chunk.Text; - ++ArgCount; - *Snippet += "${" + std::to_string(ArgCount) + ':'; + ++SnippetArg; + *Snippet += + "${" + + std::to_string(SnippetArg == CursorSnippetArg ? 0 : SnippetArg) + ':'; appendEscapeSnippet(Chunk.Text, Snippet); *Snippet += '}'; break; diff --git a/clang-tools-extra/clangd/unittests/CodeCompletionStringsTests.cpp b/clang-tools-extra/clangd/unittests/CodeCompletionStringsTests.cpp --- a/clang-tools-extra/clangd/unittests/CodeCompletionStringsTests.cpp +++ b/clang-tools-extra/clangd/unittests/CodeCompletionStringsTests.cpp @@ -22,10 +22,12 @@ CCTUInfo(Allocator), Builder(*Allocator, CCTUInfo) {} protected: - void computeSignature(const CodeCompletionString &CCS) { + void computeSignature(const CodeCompletionString &CCS, + bool CompletingPattern = false) { Signature.clear(); Snippet.clear(); - getSignature(CCS, &Signature, &Snippet); + getSignature(CCS, &Signature, &Snippet, /*RequiredQualifier=*/nullptr, + CompletingPattern); } std::shared_ptr Allocator; @@ -99,6 +101,25 @@ EXPECT_EQ(Snippet, "(${1:\\$p\\}1\\\\})"); } +TEST_F(CompletionStringTest, SnippetsInPatterns) { + auto MakeCCS = [this]() -> const CodeCompletionString & { + CodeCompletionBuilder Builder(*Allocator, CCTUInfo); + Builder.AddTypedTextChunk("namespace"); + Builder.AddChunk(CodeCompletionString::CK_HorizontalSpace); + Builder.AddPlaceholderChunk("name"); + Builder.AddChunk(CodeCompletionString::CK_Equal); + Builder.AddPlaceholderChunk("target"); + Builder.AddChunk(CodeCompletionString::CK_SemiColon); + return *Builder.TakeString(); + }; + computeSignature(MakeCCS(), /*CompletingPattern=*/false); + EXPECT_EQ(Snippet, " ${1:name} = ${2:target};"); + + // When completing a pattern, the last placeholder holds the cursor position. + computeSignature(MakeCCS(), /*CompletingPattern=*/true); + EXPECT_EQ(Snippet, " ${1:name} = ${0:target};"); +} + TEST_F(CompletionStringTest, IgnoreInformativeQualifier) { Builder.AddTypedTextChunk("X"); Builder.AddInformativeChunk("info ok");