[clang] [clang-format] Break after string literals with trailing line breaks (PR #76795)

[Owen Pan via cfe-commits]

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@@ -2499,6 +2499,15 @@ TEST_F(TokenAnnotatorTest, BraceKind) {
   EXPECT_BRACE_KIND(Tokens[6], BK_Block);
 }
 
+TEST_F(TokenAnnotatorTest, StreamOperator) {
+  auto Tokens = annotate("\"foo\\n\" << aux << \"foo\\n\" << \"foo\";");
+  ASSERT_EQ(Tokens.size(), 9u) << Tokens;
+  EXPECT_FALSE(Tokens[1]->MustBreakBefore);
+  EXPECT_FALSE(Tokens[3]->MustBreakBefore);
+  // Only break between string literals if the former ends with \n.
+  EXPECT_TRUE(Tokens[5]->MustBreakBefore);
+}
+
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owenca wrote:

I understand, but `TokenAnnotatorTest` is mainly for testing token types and has never been used for checking `MustBreakBefore` and other similar token attributes. @HazardyKnusperkeks @rymiel @mydeveloperday what do you think?

https://github.com/llvm/llvm-project/pull/76795