Fixes various bugs around the keywords class, struct and union.

This switches to parsing record definitions only if we can clearly
identify them. We're specifically allowing common patterns for
visibility control through macros and attributes, but we cannot
currently fix all instances. This fixes all known bugs we have though.

Before:
static class A f() {
  return g();
} int x;

After:
static class A f() {
  return g();
}
int x;

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@172530 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Format/UnwrappedLineParser.cpp b/lib/Format/UnwrappedLineParser.cpp
index b3671b3..fe522ac 100644
--- a/lib/Format/UnwrappedLineParser.cpp
+++ b/lib/Format/UnwrappedLineParser.cpp
@@ -320,8 +320,10 @@
     case tok::kw_struct: // fallthrough
     case tok::kw_union:  // fallthrough
     case tok::kw_class:
-      parseStructClassOrBracedList();
-      return;
+      parseRecord();
+      // A record declaration or definition is always the start of a structural
+      // element.
+      break;
     case tok::semi:
       nextToken();
       addUnwrappedLine();
@@ -569,30 +571,29 @@
   } while (!eof());
 }
 
-void UnwrappedLineParser::parseStructClassOrBracedList() {
+void UnwrappedLineParser::parseRecord() {
   nextToken();
-  do {
-    switch (FormatTok.Tok.getKind()) {
-    case tok::l_brace:
-      // FIXME: Think about how to resolve the error handling here.
-      parseBlock();
-      parseStructuralElement();
-      return;
-    case tok::semi:
-      nextToken();
-      addUnwrappedLine();
-      return;
-    case tok::equal:
-      nextToken();
-      if (FormatTok.Tok.is(tok::l_brace)) {
-        parseBracedList();
-      }
-      break;
-    default:
-      nextToken();
-      break;
+  if (FormatTok.Tok.is(tok::identifier) ||
+      FormatTok.Tok.is(tok::kw___attribute) ||
+      FormatTok.Tok.is(tok::kw___declspec)) {
+    nextToken();
+    // We can have macros or attributes in between 'class' and the class name.
+    if (FormatTok.Tok.is(tok::l_paren)) {
+      parseParens();
     }
-  } while (!eof());
+    if (FormatTok.Tok.is(tok::identifier))
+      nextToken();
+
+    if (FormatTok.Tok.is(tok::colon)) {
+      while (FormatTok.Tok.isNot(tok::l_brace)) {
+        if (FormatTok.Tok.is(tok::semi))
+          return;
+        nextToken();
+      }
+    }
+  }
+  if (FormatTok.Tok.is(tok::l_brace))
+    parseBlock();
 }
 
 void UnwrappedLineParser::parseObjCProtocolList() {
diff --git a/lib/Format/UnwrappedLineParser.h b/lib/Format/UnwrappedLineParser.h
index 487e701..08faff1 100644
--- a/lib/Format/UnwrappedLineParser.h
+++ b/lib/Format/UnwrappedLineParser.h
@@ -146,7 +146,7 @@
   void parseNamespace();
   void parseAccessSpecifier();
   void parseEnum();
-  void parseStructClassOrBracedList();
+  void parseRecord();
   void parseObjCProtocolList();
   void parseObjCUntilAtEnd();
   void parseObjCInterfaceOrImplementation();
diff --git a/unittests/Format/FormatTest.cpp b/unittests/Format/FormatTest.cpp
index f8a81b5..e9fa666 100644
--- a/unittests/Format/FormatTest.cpp
+++ b/unittests/Format/FormatTest.cpp
@@ -1290,8 +1290,37 @@
                "}");
 }
 
-TEST_F(FormatTest, BracedInitListWithElaboratedTypeSpecifier) {
+TEST_F(FormatTest, UnderstandContextOfRecordTypeKeywords) {
+  // Elaborate type variable declarations.
   verifyFormat("struct foo a = { bar };\nint n;");
+  verifyFormat("class foo a = { bar };\nint n;");
+  verifyFormat("union foo a = { bar };\nint n;");
+
+  // Elaborate types inside function definitions.
+  verifyFormat("struct foo f() {}\nint n;");
+  verifyFormat("class foo f() {}\nint n;");
+  verifyFormat("union foo f() {}\nint n;");
+
+  // Templates.
+  verifyFormat("template <class X> void f() {}\nint n;");
+  verifyFormat("template <struct X> void f() {}\nint n;");
+  verifyFormat("template <union X> void f() {}\nint n;");
+
+  // Actual definitions...
+  verifyFormat("struct {} n;");
+  verifyFormat("template <template <class T, class Y>, class Z > class X {} n;");
+  verifyFormat("union Z {\n  int n;\n} x;");
+  verifyFormat("class MACRO Z {} n;");
+  verifyFormat("class MACRO(X) Z {} n;");
+  verifyFormat("class __attribute__(X) Z {} n;");
+  verifyFormat("class __declspec(X) Z {} n;");
+
+  // Elaborate types where incorrectly parsing the structural element would
+  // break the indent.
+  verifyFormat("if (true)\n"
+               "  class X x;\n"
+               "else\n"
+               "  f();\n");
 }
 
 // FIXME: This breaks the order of the unwrapped lines: