From 50bdd60731130dbde81fa477ba8916c58039d73a Mon Sep 17 00:00:00 2001 From: mydeveloperday Date: Sat, 30 May 2020 13:00:35 +0100 Subject: [PATCH] [clang-format] [PR46130] When editing a file with unbalance {} the namespace comment fixer can incorrectly comment the wrong closing brace Summary: https://bugs.llvm.org/show_bug.cgi?id=46130 from Twitter https://twitter.com/ikautak/status/1265998988232159232 I have seen this myself many times.. if you have format on save and you work in an editor where you are constantly saving (:w muscle memory) If you are in the middle of editing and somehow you've missed a { or } in your code, somewhere, often way below where you are at the bottom of your file the namespace comment fixer will have put the namespace on the previous closing brace. This leads to you having to fix up the bottom of the file. This revision prevents that happening by performing an initial pass of the tokens and simply counting the number of `{` and `}` and ensuring they balance. If they don't balance we don't do any namespace fixing as it will likely be unstable and incorrect. Reviewed By: curdeius Subscribers: cfe-commits Tags: #clang, #clang-format Differential Revision: https://reviews.llvm.org/D80830 --- clang/lib/Format/NamespaceEndCommentsFixer.cpp | 17 +++++++++++++ .../Format/NamespaceEndCommentsFixerTest.cpp | 28 ++++++++++++++++++++++ 2 files changed, 45 insertions(+) diff --git a/clang/lib/Format/NamespaceEndCommentsFixer.cpp b/clang/lib/Format/NamespaceEndCommentsFixer.cpp index 9270715..97de45b 100644 --- a/clang/lib/Format/NamespaceEndCommentsFixer.cpp +++ b/clang/lib/Format/NamespaceEndCommentsFixer.cpp @@ -205,6 +205,23 @@ std::pair NamespaceEndCommentsFixer::analyze( const SourceManager &SourceMgr = Env.getSourceManager(); AffectedRangeMgr.computeAffectedLines(AnnotatedLines); tooling::Replacements Fixes; + + // Spin through the lines and ensure we have balanced braces. + int Braces = 0; + for (size_t I = 0, E = AnnotatedLines.size(); I != E; ++I) { + FormatToken *Tok = AnnotatedLines[I]->First; + while (Tok) { + Braces += Tok->is(tok::l_brace) ? 1 : Tok->is(tok::r_brace) ? -1 : 0; + Tok = Tok->Next; + } + } + // Don't attempt to comment unbalanced braces or this can + // lead to comments being placed on the closing brace which isn't + // the matching brace of the namespace. (occurs during incomplete editing). + if (Braces != 0) { + return {Fixes, 0}; + } + std::string AllNamespaceNames = ""; size_t StartLineIndex = SIZE_MAX; StringRef NamespaceTokenText; diff --git a/clang/unittests/Format/NamespaceEndCommentsFixerTest.cpp b/clang/unittests/Format/NamespaceEndCommentsFixerTest.cpp index fee8597..463afa6 100644 --- a/clang/unittests/Format/NamespaceEndCommentsFixerTest.cpp +++ b/clang/unittests/Format/NamespaceEndCommentsFixerTest.cpp @@ -1089,6 +1089,34 @@ TEST_F(NamespaceEndCommentsFixerTest, HandlesInlineAtEndOfLine_PR32438) { "void d() {\n" "}\n")); } + +TEST_F(NamespaceEndCommentsFixerTest, IgnoreUnbalanced) { + EXPECT_EQ("namespace A {\n" + "class Foo {\n" + "}\n" + "}// namespace A\n", + fixNamespaceEndComments("namespace A {\n" + "class Foo {\n" + "}\n" + "}\n")); + EXPECT_EQ("namespace A {\n" + "class Foo {\n" + "}\n", + fixNamespaceEndComments("namespace A {\n" + "class Foo {\n" + "}\n")); + + EXPECT_EQ("namespace A {\n" + "class Foo {\n" + "}\n" + "}\n" + "}\n", + fixNamespaceEndComments("namespace A {\n" + "class Foo {\n" + "}\n" + "}\n" + "}\n")); +} } // end namespace } // end namespace format } // end namespace clang -- 2.7.4