Adds parser recovery to the class right brace and handles stray semicolons in a class

compiler/java/com/google/dart/compiler/parser/DartParser.java

Index: compiler/java/com/google/dart/compiler/parser/DartParser.java
diff --git a/compiler/java/com/google/dart/compiler/parser/DartParser.java b/compiler/java/com/google/dart/compiler/parser/DartParser.java
index 3a5f1a42c5604ef109070690ef52415d59365e9a..31904554db31c9b8144ec8fa313653ea64ccefc1 100644
--- a/compiler/java/com/google/dart/compiler/parser/DartParser.java
+++ b/compiler/java/com/google/dart/compiler/parser/DartParser.java
@@ -665,17 +665,7 @@ public class DartParser extends CompletionHooksParserBase {
 
     // Parse the members.
     List<DartNode> members = new ArrayList<DartNode>();
-    if (optional(Token.LBRACE)) {
-      while (!match(Token.RBRACE) && !EOS() && !looksLikeTopLevelKeyword()) {
-        DartNode member = parseFieldOrMethod(true);
-        if (member != null) {
-          members.add(member);
-        }
-      }
-      expectCloseBrace();
-    } else {
-      reportErrorWithoutAdvancing(ParserErrorCode.EXPECTED_CLASS_DECLARATION_LBRACE);
-    }
+    parseClassOrInterfaceBody(members);
 
     if (isParsingInterface) {
       return done(new DartClass(name, superType, interfaces, members, typeParameters, defaultClass));
@@ -690,6 +680,31 @@ public class DartParser extends CompletionHooksParserBase {
     }
   }
 
+  /**
+   * Helper for {@link #parseClass()}.
+   *
+   * '{' classMemberDefinition* '}'
+   *
+   */
+  @Terminals(tokens={Token.RBRACE, Token.SEMICOLON})
+  private void parseClassOrInterfaceBody(List<DartNode> members) {
+    if (optional(Token.LBRACE)) {
+      while (!match(Token.RBRACE) && !EOS() && !looksLikeTopLevelKeyword()) {
+        DartNode member = parseFieldOrMethod(true);
+        if (member != null) {
+          members.add(member);
+        }
+        // Recover at a semicolon
+        if (optional(Token.SEMICOLON)) {
+          reportUnexpectedToken(position(), null, Token.SEMICOLON);
+        }
+      }
+      expectCloseBrace(true);
+    } else {
+      reportErrorWithoutAdvancing(ParserErrorCode.EXPECTED_CLASS_DECLARATION_LBRACE);
+    }
+  }
+
   private boolean optionalDeprecatedFactory() {
     if (optionalPseudoKeyword(FACTORY_KEYWORD)) {
       reportError(position(), ParserErrorCode.DEPRECATED_USE_OF_FACTORY_KEYWORD);
@@ -2256,7 +2271,7 @@ public class DartParser extends CompletionHooksParserBase {
   @Terminals(tokens={Token.RBRACE, Token.COMMA})
   private DartExpression parseMapLiteral(boolean isConst, List<DartTypeNode> typeArguments) {
     beginMapLiteral();
-    expect(Token.LBRACE);
+    boolean foundOpenBrace = expect(Token.LBRACE);
     boolean save = setAllowFunctionExpression(true);
     List<DartMapLiteralEntry> entries = new ArrayList<DartMapLiteralEntry>();
 
@@ -2300,7 +2315,7 @@ public class DartParser extends CompletionHooksParserBase {
       }
     }
 
-    expectCloseBrace();
+    expectCloseBrace(foundOpenBrace);
     setAllowFunctionExpression(save);
     return done(new DartMapLiteral(isConst, typeArguments, entries));
   }
@@ -3010,7 +3025,7 @@ public class DartParser extends CompletionHooksParserBase {
       }
       beginBlock();
       List<DartStatement> statements = new ArrayList<DartStatement>();
-      expect(Token.LBRACE);
+      boolean foundOpenBrace = expect(Token.LBRACE);
       while (!match(Token.RBRACE) && !EOS()) {
         if (looksLikeTopLevelKeyword()) {
           reportErrorWithoutAdvancing(ParserErrorCode.UNEXPECTED_TOKEN);
@@ -3022,7 +3037,7 @@ public class DartParser extends CompletionHooksParserBase {
         }
         statements.add(newStatement);
       }
-      expectCloseBrace();
+      expectCloseBrace(foundOpenBrace);
       return done(new DartBlock(statements));
     }
   }
@@ -3496,33 +3511,30 @@ public class DartParser extends CompletionHooksParserBase {
    * Expect a close brace, reporting an error and consuming tokens until a
    * plausible continuation is found if it isn't present.
    */
-  private void expectCloseBrace() {
+  private void expectCloseBrace(boolean foundOpenBrace) {
     // If a top level keyword is seen, bail out to recover.
     if (looksLikeTopLevelKeyword()) {
-      reportErrorWithoutAdvancing(ParserErrorCode.UNEXPECTED_TOKEN);
+      reportUnexpectedToken(position(), Token.RBRACE, peek(0));
       return;
     }
-    int braceCount = 1;
-    switch (peek(0)) {
-      case RBRACE:
-        expect(Token.RBRACE);
-        return;
 
-      case EOS:
-      case SEMICOLON:
-        reportErrorWithoutAdvancing(ParserErrorCode.UNEXPECTED_TOKEN);
-        return;
-
-      case LBRACE:
-        ++braceCount;
-        //$FALL-THROUGH$
-      default:
-        reportErrorWithoutAdvancing(ParserErrorCode.UNEXPECTED_TOKEN);
-        break;
+    int braceCount = 0;
+    if (foundOpenBrace) {
+      braceCount++;
+    }
+    Token nextToken = peek(0);
+    if (expect(Token.RBRACE)) {
+      return;
+    }
+    if (nextToken == Token.LBRACE) {
+      braceCount++;
     }
 
     // eat tokens until we get a matching close brace or end of stream
     while (braceCount > 0) {
+      if (looksLikeTopLevelKeyword()) {
+        return;
+      }
       switch (next()) {
         case RBRACE:
           braceCount--;
@@ -3888,7 +3900,7 @@ public class DartParser extends CompletionHooksParserBase {
     expectCloseParen();
 
     List<DartSwitchMember> members = new ArrayList<DartSwitchMember>();
-    expect(Token.LBRACE);
+    boolean foundOpenBrace = expect(Token.LBRACE);
 
     boolean done = optional(Token.RBRACE);
     while (!done) {
@@ -3913,7 +3925,7 @@ public class DartParser extends CompletionHooksParserBase {
         if (peek(0) != Token.EOS) {
           members.add(parseDefaultMember(label));
         }
-        expectCloseBrace();
+        expectCloseBrace(foundOpenBrace);
         done = true; // Ensure termination.
       }
     }