[clang-format] Fix a bug in BCIS_AfterColon and ColumnLimit: 0 (#127964)

Fixes #127622

Author: owenca

clang/lib/Format/ContinuationIndenter.cpp

@@ -473,9 +473,8 @@ bool ContinuationIndenter::mustBreak(const LineState &State) {
       (State.Column + State.Line->Last->TotalLength - Previous.TotalLength >
            getColumnLimit(State) ||
        CurrentState.BreakBeforeParameter) &&
-      (!Current.isTrailingComment() || Current.NewlinesBefore > 0) &&
-      (Style.BreakConstructorInitializers != FormatStyle::BCIS_BeforeColon ||
-       Style.ColumnLimit > 0 || Current.NewlinesBefore > 0)) {
+      ((!Current.isTrailingComment() && Style.ColumnLimit > 0) ||
+       Current.NewlinesBefore > 0)) {
     return true;
   }
 

clang/unittests/Format/FormatTest.cpp

@@ -8292,31 +8292,40 @@ TEST_F(FormatTest, BreakConstructorInitializersAfterColon) {
                Style);
 
   Style.ColumnLimit = 0;
-  verifyFormat("SomeClass::Constructor() :\n"
-               "    a(a) {}",
-               Style);
-  verifyFormat("SomeClass::Constructor() noexcept :\n"
-               "    a(a) {}",
-               Style);
-  verifyFormat("SomeClass::Constructor() :\n"
-               "    a(a), b(b), c(c) {}",
-               Style);
-  verifyFormat("SomeClass::Constructor() :\n"
-               "    a(a) {\n"
-               "  foo();\n"
-               "  bar();\n"
-               "}",
+  verifyNoChange("SomeClass::Constructor() :\n"
+                 "    a(a) {}",
+                 Style);
+  verifyNoChange("SomeClass::Constructor() noexcept :\n"
+                 "    a(a) {}",
+                 Style);
+  verifyNoChange("SomeClass::Constructor() :\n"
+                 "    a(a), b(b), c(c) {}",
+                 Style);
+  verifyNoChange("SomeClass::Constructor() :\n"
+                 "    a(a) {\n"
+                 "  foo();\n"
+                 "  bar();\n"
+                 "}",
+                 Style);
+  verifyFormat("struct Foo {\n"
+               "  int x;\n"
+               "  Foo() : x(0) {}\n"
+               "};",
+               "struct Foo {\n"
+               "  int x;\n"
+               "  Foo():x(0) {}\n"
+               "};",
                Style);
 
   Style.AllowShortFunctionsOnASingleLine = FormatStyle::SFS_None;
-  verifyFormat("SomeClass::Constructor() :\n"
-               "    a(a), b(b), c(c) {\n"
-               "}",
-               Style);
-  verifyFormat("SomeClass::Constructor() :\n"
-               "    a(a) {\n"
-               "}",
-               Style);
+  verifyNoChange("SomeClass::Constructor() :\n"
+                 "    a(a), b(b), c(c) {\n"
+                 "}",
+                 Style);
+  verifyNoChange("SomeClass::Constructor() :\n"
+                 "    a(a) {\n"
+                 "}",
+                 Style);
 
   Style.ColumnLimit = 80;
   Style.AllowShortFunctionsOnASingleLine = FormatStyle::SFS_All;