[clang-format] Add style option `PenaltyBreakBeforeMemberAccess` (#118409)

The penalty for breaking before a member access is hard-coded to 150.
Add a configuration option to allow setting it.

---------

Co-authored-by: Owen Pan <owenpiano@gmail.com>

2 files changed, 20 insertions, 0 deletions

diff --git a/clang/unittests/Format/ConfigParseTest.cpp b/clang/unittests/Format/ConfigParseTest.cpp
index 9746aa3..1078844 100644
--- a/clang/unittests/Format/ConfigParseTest.cpp
+++ b/clang/unittests/Format/ConfigParseTest.cpp
@@ -266,6 +266,8 @@ TEST(ConfigParseTest, ParsesConfiguration) {
   CHECK_PARSE("PenaltyBreakAssignment: 1234", PenaltyBreakAssignment, 1234u);
   CHECK_PARSE("PenaltyBreakBeforeFirstCallParameter: 1234",
               PenaltyBreakBeforeFirstCallParameter, 1234u);
+  CHECK_PARSE("PenaltyBreakBeforeMemberAccess: 1234",
+              PenaltyBreakBeforeMemberAccess, 1234u);
   CHECK_PARSE("PenaltyBreakTemplateDeclaration: 1234",
               PenaltyBreakTemplateDeclaration, 1234u);
   CHECK_PARSE("PenaltyBreakOpenParenthesis: 1234", PenaltyBreakOpenParenthesis,
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index 2654615..57f1222 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -22365,6 +22365,24 @@ TEST_F(FormatTest, BreakPenaltyAfterForLoopLParen) {
                Style);
 }
 
+TEST_F(FormatTest, BreakPenaltyBeforeMemberAccess) {
+  auto Style = getLLVMStyle();
+  EXPECT_EQ(Style.PenaltyBreakBeforeMemberAccess, 150u);
+
+  Style.ColumnLimit = 60;
+  Style.PenaltyBreakBeforeMemberAccess = 110;
+  verifyFormat("aaaaaaaa.aaaaaaaa.bbbbbbbb()\n"
+               "    .ccccccccccccccccccccc(dddddddd);\n"
+               "aaaaaaaa.aaaaaaaa\n"
+               "    .bbbbbbbb(cccccccccccccccccccccccccccccccc);",
+               Style);
+
+  Style.ColumnLimit = 13;
+  verifyFormat("foo->bar\n"
+               "    .b(a);",
+               Style);
+}
+
 TEST_F(FormatTest, BreakPenaltyScopeResolution) {
   FormatStyle Style = getLLVMStyle();
   Style.ColumnLimit = 20;