From 8c099ce72d480fbff943613c7482992449fafe2d Mon Sep 17 00:00:00 2001 From: Artem Dergachev Date: Tue, 23 Apr 2019 21:15:26 +0000 Subject: [PATCH] Re-apply r357823 "[Lexer] NFC: Fix an off-by-one bug in getAsCharRange()." It now comes with a follow-up fix for the clients of this API in clangd and clang-tidy. Differential Revision: https://reviews.llvm.org/D59977 llvm-svn: 359035 --- .../modernize/ConcatNestedNamespacesCheck.cpp | 1 + .../clang-tidy/readability/NamespaceCommentCheck.cpp | 5 ++++- clang-tools-extra/unittests/clangd/SelectionTests.cpp | 2 +- clang/include/clang/Basic/PlistSupport.h | 6 +++++- clang/include/clang/Lex/Lexer.h | 2 +- clang/unittests/Lex/LexerTest.cpp | 19 +++++++++++++++++++ 6 files changed, 31 insertions(+), 4 deletions(-) diff --git a/clang-tools-extra/clang-tidy/modernize/ConcatNestedNamespacesCheck.cpp b/clang-tools-extra/clang-tidy/modernize/ConcatNestedNamespacesCheck.cpp index 33ac856..c1539bfd 100644 --- a/clang-tools-extra/clang-tidy/modernize/ConcatNestedNamespacesCheck.cpp +++ b/clang-tools-extra/clang-tidy/modernize/ConcatNestedNamespacesCheck.cpp @@ -39,6 +39,7 @@ static bool alreadyConcatenated(std::size_t NumCandidates, const SourceRange &ReplacementRange, const SourceManager &Sources, const LangOptions &LangOpts) { + // FIXME: This logic breaks when there is a comment with ':'s in the middle. CharSourceRange TextRange = Lexer::getAsCharRange(ReplacementRange, Sources, LangOpts); StringRef CurrentNamespacesText = diff --git a/clang-tools-extra/clang-tidy/readability/NamespaceCommentCheck.cpp b/clang-tools-extra/clang-tidy/readability/NamespaceCommentCheck.cpp index 17184ec..6428f8c 100644 --- a/clang-tools-extra/clang-tidy/readability/NamespaceCommentCheck.cpp +++ b/clang-tools-extra/clang-tidy/readability/NamespaceCommentCheck.cpp @@ -102,11 +102,14 @@ void NamespaceCommentCheck::check(const MatchFinder::MatchResult &Result) { } } + // FIXME: This probably breaks on comments between the namespace and its '{'. auto TextRange = Lexer::getAsCharRange(SourceRange(NestedNamespaceBegin, LBracketLocation), Sources, getLangOpts()); StringRef NestedNamespaceName = - Lexer::getSourceText(TextRange, Sources, getLangOpts()).rtrim(); + Lexer::getSourceText(TextRange, Sources, getLangOpts()) + .rtrim('{') // Drop the { itself. + .rtrim(); // Drop any whitespace before it. bool IsNested = NestedNamespaceName.contains(':'); if (IsNested) diff --git a/clang-tools-extra/unittests/clangd/SelectionTests.cpp b/clang-tools-extra/unittests/clangd/SelectionTests.cpp index 2d96271..ac9facc 100644 --- a/clang-tools-extra/unittests/clangd/SelectionTests.cpp +++ b/clang-tools-extra/unittests/clangd/SelectionTests.cpp @@ -45,7 +45,7 @@ Range nodeRange(const SelectionTree::Node *N, ParsedAST &AST) { CharSourceRange R = Lexer::getAsCharRange(SR, SM, AST.getASTContext().getLangOpts()); return Range{offsetToPosition(Buffer, SM.getFileOffset(R.getBegin())), - offsetToPosition(Buffer, SM.getFileOffset(R.getEnd()) + 1)}; + offsetToPosition(Buffer, SM.getFileOffset(R.getEnd()))}; } std::string nodeKind(const SelectionTree::Node *N) { diff --git a/clang/include/clang/Basic/PlistSupport.h b/clang/include/clang/Basic/PlistSupport.h index f81b469..557462a 100644 --- a/clang/include/clang/Basic/PlistSupport.h +++ b/clang/include/clang/Basic/PlistSupport.h @@ -127,7 +127,11 @@ inline void EmitRange(raw_ostream &o, const SourceManager &SM, assert(R.isCharRange() && "cannot handle a token range"); Indent(o, indent) << "\n"; EmitLocation(o, SM, R.getBegin(), FM, indent + 1); - EmitLocation(o, SM, R.getEnd(), FM, indent + 1); + + // The ".getLocWithOffset(-1)" emulates the behavior of an off-by-one bug + // in Lexer that is already fixed. It is here for backwards compatibility + // even though it is incorrect. + EmitLocation(o, SM, R.getEnd().getLocWithOffset(-1), FM, indent + 1); Indent(o, indent) << "\n"; } diff --git a/clang/include/clang/Lex/Lexer.h b/clang/include/clang/Lex/Lexer.h index 4a8a0f6..69cfe62 100644 --- a/clang/include/clang/Lex/Lexer.h +++ b/clang/include/clang/Lex/Lexer.h @@ -382,7 +382,7 @@ public: SourceLocation End = getLocForEndOfToken(Range.getEnd(), 0, SM, LangOpts); return End.isInvalid() ? CharSourceRange() : CharSourceRange::getCharRange( - Range.getBegin(), End.getLocWithOffset(-1)); + Range.getBegin(), End); } static CharSourceRange getAsCharRange(CharSourceRange Range, const SourceManager &SM, diff --git a/clang/unittests/Lex/LexerTest.cpp b/clang/unittests/Lex/LexerTest.cpp index 320b60e..7b14f56 100644 --- a/clang/unittests/Lex/LexerTest.cpp +++ b/clang/unittests/Lex/LexerTest.cpp @@ -513,4 +513,23 @@ TEST_F(LexerTest, StringizingRasString) { EXPECT_EQ(String6, R"(a\\\n\n\n \\\\b)"); } +TEST_F(LexerTest, CharRangeOffByOne) { + std::vector toks = Lex(R"(#define MOO 1 + void foo() { MOO; })"); + const Token &moo = toks[5]; + + EXPECT_EQ(getSourceText(moo, moo), "MOO"); + + SourceRange R{moo.getLocation(), moo.getLocation()}; + + EXPECT_TRUE( + Lexer::isAtStartOfMacroExpansion(R.getBegin(), SourceMgr, LangOpts)); + EXPECT_TRUE( + Lexer::isAtEndOfMacroExpansion(R.getEnd(), SourceMgr, LangOpts)); + + CharSourceRange CR = Lexer::getAsCharRange(R, SourceMgr, LangOpts); + + EXPECT_EQ(Lexer::getSourceText(CR, SourceMgr, LangOpts), "MOO"); // Was "MO". +} + } // anonymous namespace -- 2.7.4