[clang-format] Fix brace wrapping for Java records (#164711)

The brace wrapping for Java records should now behave similar to
classes. Before, opening braces for Java records were always placed in
the same line as the record definition.

Author: hannesbraun

clang/lib/Format/UnwrappedLineFormatter.cpp

@@ -285,7 +285,8 @@ class LineJoiner {
       if (Tok && Tok->is(tok::kw_typedef))
         Tok = Tok->getNextNonComment();
       if (Tok && Tok->isOneOf(tok::kw_class, tok::kw_struct, tok::kw_union,
-                              tok::kw_extern, Keywords.kw_interface)) {
+                              tok::kw_extern, Keywords.kw_interface,
+                              Keywords.kw_record)) {
         return !Style.BraceWrapping.SplitEmptyRecord && EmptyBlock
                    ? tryMergeSimpleBlock(I, E, Limit)
                    : 0;
@@ -498,7 +499,8 @@ class LineJoiner {
         ShouldMerge = Style.AllowShortEnumsOnASingleLine;
       } else if (TheLine->Last->is(TT_CompoundRequirementLBrace)) {
         ShouldMerge = Style.AllowShortCompoundRequirementOnASingleLine;
-      } else if (TheLine->Last->isOneOf(TT_ClassLBrace, TT_StructLBrace)) {
+      } else if (TheLine->Last->isOneOf(TT_ClassLBrace, TT_StructLBrace,
+                                        TT_RecordLBrace)) {
         // NOTE: We use AfterClass (whereas AfterStruct exists) for both classes
         // and structs, but it seems that wrapping is still handled correctly
         // elsewhere.
@@ -507,7 +509,7 @@ class LineJoiner {
                        !Style.BraceWrapping.SplitEmptyRecord);
       } else if (TheLine->InPPDirective ||
                  TheLine->First->isNoneOf(tok::kw_class, tok::kw_enum,
-                                          tok::kw_struct)) {
+                                          tok::kw_struct, Keywords.kw_record)) {
         // Try to merge a block with left brace unwrapped that wasn't yet
         // covered.
         ShouldMerge = !Style.BraceWrapping.AfterFunction ||

clang/lib/Format/UnwrappedLineParser.cpp

@@ -948,7 +948,11 @@ static bool isIIFE(const UnwrappedLine &Line,
 }
 
 static bool ShouldBreakBeforeBrace(const FormatStyle &Style,
-                                   const FormatToken &InitialToken) {
+                                   const FormatToken &InitialToken,
+                                   const bool IsJavaRecord) {
+  if (IsJavaRecord)
+    return Style.BraceWrapping.AfterClass;
+
   tok::TokenKind Kind = InitialToken.Tok.getKind();
   if (InitialToken.is(TT_NamespaceMacro))
     Kind = tok::kw_namespace;
@@ -3200,7 +3204,7 @@ void UnwrappedLineParser::parseNamespace() {
   if (FormatTok->is(tok::l_brace)) {
     FormatTok->setFinalizedType(TT_NamespaceLBrace);
 
-    if (ShouldBreakBeforeBrace(Style, InitialToken))
+    if (ShouldBreakBeforeBrace(Style, InitialToken, /*IsJavaRecord=*/false))
       addUnwrappedLine();
 
     unsigned AddLevels =
@@ -3865,7 +3869,7 @@ bool UnwrappedLineParser::parseEnum() {
   }
 
   if (!Style.AllowShortEnumsOnASingleLine &&
-      ShouldBreakBeforeBrace(Style, InitialToken)) {
+      ShouldBreakBeforeBrace(Style, InitialToken, /*IsJavaRecord=*/false)) {
     addUnwrappedLine();
   }
   // Parse enum body.
@@ -4160,7 +4164,7 @@ void UnwrappedLineParser::parseRecord(bool ParseAsExpr, bool IsJavaRecord) {
     if (ParseAsExpr) {
       parseChildBlock();
     } else {
-      if (ShouldBreakBeforeBrace(Style, InitialToken))
+      if (ShouldBreakBeforeBrace(Style, InitialToken, IsJavaRecord))
         addUnwrappedLine();
 
       unsigned AddLevels = Style.IndentAccessModifiers ? 2u : 1u;

clang/unittests/Format/FormatTestJava.cpp

@@ -848,6 +848,19 @@ TEST_F(FormatTestJava, TextBlock) {
                  "              Pat Q. Smith");
 }
 
+TEST_F(FormatTestJava, BreakAfterRecord) {
+  auto Style = getLLVMStyle(FormatStyle::LK_Java);
+  Style.EmptyLineBeforeAccessModifier = FormatStyle::ELBAMS_Never;
+  Style.BreakBeforeBraces = FormatStyle::BS_Custom;
+  Style.BraceWrapping.AfterClass = true;
+  Style.BraceWrapping.SplitEmptyRecord = true;
+
+  verifyFormat("public record Foo(int i)\n"
+               "{\n"
+               "}",
+               "public record Foo(int i) {}", Style);
+}
+
 } // namespace
 } // namespace test
 } // namespace format