[clang] clang-format: Add splitting for strings with user-defined suffixes (PR #167150)

[Björn Schäpers via cfe-commits]

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@@ -15838,6 +15838,10 @@ TEST_F(FormatTest, BreaksWideAndNSStringLiterals) {
                "@\"NSString literal\";", getGoogleStyleWithColumns(19));
   verifyFormat(R"(NSString *s = @"那那那那";)", getLLVMStyleWithColumns(26));
 
+  EXPECT_EQ("L\"suffixed \"\n"
+            "L\"string\"_s;",
+            format("L\"suffixed string\"_s;", getLLVMStyleWithColumns(19)));
----------------
HazardyKnusperkeks wrote:

```suggestion
  verifyFormat("L\"suffixed \"\n"
            "L\"string\"_s;",
            "L\"suffixed string\"_s;", getLLVMStyleWithColumns(19)));
```

https://github.com/llvm/llvm-project/pull/167150