[clang] [clang-format] Add KwBreakBeforeCaseLabel (PR #227668)

[Björn Schäpers via cfe-commits]

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@@ -2833,6 +2833,56 @@ TEST_F(FormatTest, FormatsSwitchStatement) {
                Style);
 }
 
+TEST_F(FormatTest, FormatsSwitchStatementKwBreakBeforeCase) {
+  FormatStyle Style = getLLVMStyle();
+  Style.IndentCaseLabels = true;
+  Style.KwBreakBeforeCaseLabel = true;
+
+  verifyFormat("switch (n) {\n"
+               "  break; case 0:;\n"
+               "}",
+               Style);
+
+  verifyFormat("switch (n) {\n"
+               "  break; case 0: {\n"
+               "    return false;\n"
+               "  }\n"
+               "  break; case 1:\n"
+               "  break; default: {\n"
+               "    return true;\n"
+               "  }\n"
+               "}",
+               Style);
+
+  verifyFormat("switch (n) {\n"
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HazardyKnusperkeks wrote:

The two argument variant should suffice, it uses `messUp` to remove all whitespace and line breaks.

https://github.com/llvm/llvm-project/pull/227668