From: Alexander Kornienko <alexfh@google.com>
Date: Tue, 15 Apr 2014 14:52:43 +0000 (+0000)
Subject: Fix assertion when breaking string literals with tab characters.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=47caeab34c7b4bdf1bb0e5aa0daaa2b587dbce20;p=clang

Fix assertion when breaking string literals with tab characters.

Summary: Fixes http://llvm.org/PR19368

Reviewers: djasper, klimek

Reviewed By: klimek

CC: cfe-commits, klimek

Differential Revision: http://reviews.llvm.org/D3379

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@206295 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Format/ContinuationIndenter.cpp b/lib/Format/ContinuationIndenter.cpp
index 35dc182a2d..9311ca481c 100644
--- a/lib/Format/ContinuationIndenter.cpp
+++ b/lib/Format/ContinuationIndenter.cpp
@@ -961,6 +961,12 @@ unsigned ContinuationIndenter::breakProtrudingToken(const FormatToken &Current,
         break;
       }
 
+      // When breaking before a tab character, it may be moved by a few columns,
+      // but will still be expanded to the next tab stop, so we don't save any
+      // columns.
+      if (NewRemainingTokenColumns == RemainingTokenColumns)
+        break;
+
       assert(NewRemainingTokenColumns < RemainingTokenColumns);
       if (!DryRun)
         Token->insertBreak(LineIndex, TailOffset, Split, Whitespaces);
diff --git a/unittests/Format/FormatTest.cpp b/unittests/Format/FormatTest.cpp
index 708ddfa091..f1442e03b6 100644
--- a/unittests/Format/FormatTest.cpp
+++ b/unittests/Format/FormatTest.cpp
@@ -6366,7 +6366,7 @@ TEST_F(FormatTest, ReformatRegionAdjustsIndent) {
                    67, 0, getLLVMStyle()));
 }
 
-TEST_F(FormatTest, BreakStringLiterals) {
+TEST_F(FormatTest, BreaksStringLiterals) {
   EXPECT_EQ("\"some text \"\n"
             "\"other\";",
             format("\"some text other\";", getLLVMStyleWithColumns(12)));
@@ -6526,6 +6526,16 @@ TEST_F(FormatTest, BreakStringLiterals) {
       format("#define A \"some text other\";", AlignLeft));
 }
 
+TEST_F(FormatTest, BreaksStringLiteralsWithTabs) {
+  EXPECT_EQ(
+      "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+      "(\n"
+      "    \"x\t\");",
+      format("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+             "aaaaaaa("
+             "\"x\t\");"));
+}
+
 TEST_F(FormatTest, BreaksWideAndNSStringLiterals) {
   EXPECT_EQ(
       "u8\"utf8 string \"\n"