Re-land of CL 2990703002, adding fixes to analyzer_test and error_test.

pkg/analyzer/lib/src/generated/parser.dart

Index: pkg/analyzer/lib/src/generated/parser.dart
diff --git a/pkg/analyzer/lib/src/generated/parser.dart b/pkg/analyzer/lib/src/generated/parser.dart
index a18a016b41fb8399164cce1841d1d118501b2787..5f67ad19f2399d91387942a51721feb026de126c 100644
--- a/pkg/analyzer/lib/src/generated/parser.dart
+++ b/pkg/analyzer/lib/src/generated/parser.dart
@@ -351,7 +351,7 @@ class Parser {
   bool get hasReturnTypeInTypeAlias {
     // TODO(brianwilkerson) This is too expensive as implemented and needs to be
     // re-implemented or removed.
-    Token next = skipReturnType(_currentToken);
+    Token next = skipTypeAnnotation(_currentToken);
     if (next == null) {
       return false;
     }
@@ -449,10 +449,7 @@ class Parser {
    */
   bool isFunctionDeclaration() {
     Keyword keyword = _currentToken.keyword;
-    if (keyword == Keyword.VOID) {
-      return true;
-    }
-    Token afterReturnType = skipTypeName(_currentToken);
+    Token afterReturnType = skipTypeWithoutFunction(_currentToken);
     if (afterReturnType != null &&
         _tokenMatchesKeyword(afterReturnType, Keyword.FUNCTION)) {
       afterReturnType = skipGenericFunctionTypeAfterReturnType(afterReturnType);
@@ -1328,9 +1325,6 @@ class Parser {
             TokenType.COMMA,
             TokenType.SEMICOLON
           ])) {
-        if (returnType is! GenericFunctionType) {
-          _reportErrorForNode(ParserErrorCode.VOID_VARIABLE, returnType);
-        }
         return parseInitializedIdentifierList(
             commentAndMetadata,
             modifiers.staticKeyword,
@@ -2137,9 +2131,6 @@ class Parser {
             TokenType.COMMA,
             TokenType.SEMICOLON
           ])) {
-        if (returnType is! GenericFunctionType) {
-          _reportErrorForNode(ParserErrorCode.VOID_VARIABLE, returnType);
-        }
         return astFactory.topLevelVariableDeclaration(
             commentAndMetadata.comment,
             commentAndMetadata.metadata,
@@ -2217,7 +2208,7 @@ class Parser {
               null, _validateModifiersForTopLevelVariable(modifiers), null),
           _expect(TokenType.SEMICOLON));
     }
-    TypeAnnotation returnType = parseReturnType(false);
+    TypeAnnotation returnType = parseTypeAnnotation(false);
     keyword = _currentToken.keyword;
     next = _peek();
     if ((keyword == Keyword.GET || keyword == Keyword.SET) &&
@@ -2892,7 +2883,7 @@ class Parser {
         keywordToken = null;
       }
     } else if (_isTypedIdentifier(_currentToken)) {
-      type = parseReturnType(false);
+      type = parseTypeAnnotation(false);
     } else if (inFunctionType && _matchesIdentifier()) {
       type = parseTypeAnnotation(false);
     } else if (!optional) {
@@ -3414,7 +3405,7 @@ class Parser {
    *       | '(' normalParameterTypes ',' optionalParameterTypes ')' |
    *       | '(' optionalParameterTypes ')'
    *     normalParameterTypes ::=
-   *     normalParameterType (',' normalParameterType)*
+   *         normalParameterType (',' normalParameterType)*
    *     normalParameterType ::=
    *         type | typedIdentifier
    *     optionalParameterTypes ::=
@@ -4137,9 +4128,6 @@ class Parser {
               TokenType.COMMA,
               TokenType.SEMICOLON
             ])) {
-          if (returnType is! GenericFunctionType) {
-            _reportErrorForNode(ParserErrorCode.VOID_VARIABLE, returnType);
-          }
           return _parseVariableDeclarationStatementAfterType(
               commentAndMetadata, null, returnType);
         } else {
@@ -4217,9 +4205,6 @@ class Parser {
             TokenType.COMMA,
             TokenType.SEMICOLON
           ])) {
-        if (returnType is! GenericFunctionType) {
-          _reportErrorForNode(ParserErrorCode.VOID_VARIABLE, returnType);
-        }
         return _parseVariableDeclarationStatementAfterType(
             commentAndMetadata, null, returnType);
       } else {
@@ -4365,15 +4350,10 @@ class Parser {
       //_reportErrorForToken(ParserErrorCode.MISSING_PARAMETERS, typeParameters.endToken);
     }
     TypeAnnotation type = holder.type;
-    if (type != null) {
-      if (type is TypeName &&
-          _tokenMatchesKeyword(type.name.beginToken, Keyword.VOID)) {
-        _reportErrorForToken(
-            ParserErrorCode.VOID_PARAMETER, type.name.beginToken);
-      } else if (holder.keyword != null &&
-          _tokenMatchesKeyword(holder.keyword, Keyword.VAR)) {
-        _reportErrorForToken(ParserErrorCode.VAR_AND_TYPE, holder.keyword);
-      }
+    if (type != null &&
+        holder.keyword != null &&
+        _tokenMatchesKeyword(holder.keyword, Keyword.VAR)) {
+      _reportErrorForToken(ParserErrorCode.VAR_AND_TYPE, holder.keyword);
     }
     if (thisKeyword != null) {
       // TODO(brianwilkerson) If there are type parameters but no parameters,
@@ -4701,14 +4681,14 @@ class Parser {
     if (keyword == Keyword.AS) {
       Token asOperator = getAndAdvance();
       return astFactory.asExpression(
-          expression, asOperator, parseTypeAnnotation(true));
+          expression, asOperator, parseTypeNotVoid(true));
     } else if (keyword == Keyword.IS) {
       Token isOperator = getAndAdvance();
       Token notOperator = null;
       if (_matches(TokenType.BANG)) {
         notOperator = getAndAdvance();
       }
-      TypeAnnotation type = parseTypeAnnotation(true);
+      TypeAnnotation type = parseTypeNotVoid(true);
       return astFactory.isExpression(expression, isOperator, notOperator, type);
     } else if (_currentToken.type.isRelationalOperator) {
       Token operator = getAndAdvance();
@@ -4747,26 +4727,6 @@ class Parser {
     return astFactory.returnStatement(returnKeyword, expression, semicolon);
   }
 
-  /**
-   * Parse a return type. Return the return type that was parsed.
-   *
-   *     returnType ::=
-   *         'void'
-   *       | type
-   */
-  TypeAnnotation parseReturnType(bool inExpression) {
-    if (_currentToken.keyword == Keyword.VOID) {
-      if (_atGenericFunctionTypeAfterReturnType(_peek())) {
-        return parseTypeAnnotation(false);
-      } else {
-        return astFactory.typeName(
-            astFactory.simpleIdentifier(getAndAdvance()), null);
-      }
-    } else {
-      return parseTypeAnnotation(inExpression);
-    }
-  }
-
   /**
    * Parse a setter. The [commentAndMetadata] is the documentation comment and
    * metadata to be associated with the declaration. The [externalKeyword] is
@@ -5130,7 +5090,7 @@ class Parser {
       TypeName exceptionType = null;
       if (_matchesKeyword(Keyword.ON)) {
         onKeyword = getAndAdvance();
-        exceptionType = parseTypeAnnotation(false);
+        exceptionType = parseTypeNotVoid(false);
       }
       Token catchKeyword = null;
       Token leftParenthesis = null;
@@ -5218,6 +5178,27 @@ class Parser {
    *       | functionType
    */
   TypeAnnotation parseTypeAnnotation(bool inExpression) {
+    TypeAnnotation type = null;
+    if (_atGenericFunctionTypeAfterReturnType(_currentToken)) {
+      // Generic function type with no return type.
+      type = parseGenericFunctionTypeAfterReturnType(null);
+    } else {
+      type = parseTypeWithoutFunction(inExpression);
+    }
+    while (_atGenericFunctionTypeAfterReturnType(_currentToken)) {
+      type = parseGenericFunctionTypeAfterReturnType(type);
+    }
+    return type;
+  }
+
+  /**
+   * Parse a type which is not `void`.
+   *
+   *     typeNotVoid ::=
+   *         functionType
+   *       | typeNotVoidWithoutFunction
+   */
+  TypeAnnotation parseTypeNotVoid(bool inExpression) {
     TypeAnnotation type = null;
     if (_atGenericFunctionTypeAfterReturnType(_currentToken)) {
       // Generic function type with no return type.
@@ -5235,6 +5216,22 @@ class Parser {
     return type;
   }
 
+  /**
+   * Parse a type which is not a function type.
+   *
+   *     typeWithoutFunction ::=
+   *         `void`
+   *       | typeNotVoidWithoutFunction
+   */
+  TypeAnnotation parseTypeWithoutFunction(bool inExpression) {
+    if (_currentToken.keyword == Keyword.VOID) {
+      return astFactory.typeName(
+          astFactory.simpleIdentifier(getAndAdvance()), null);
+    } else {
+      return parseTypeName(inExpression);
+    }
+  }
+
   /**
    * Parse a list of type arguments. Return the type argument list that was
    * parsed.
@@ -5260,11 +5257,14 @@ class Parser {
   }
 
   /**
-   * Parse a type name. Return the type name that was parsed.
+   * Parse a type which is not void and is not a function type. Return the type
+   * that was parsed.
    *
-   *     type ::=
+   *     typeNotVoidWithoutFunction ::=
    *         qualified typeArguments?
    */
+  // TODO(eernst): Rename this to `parseTypeNotVoidWithoutFunction`?
+  // Apparently,  it was named `parseTypeName` before type arguments existed.
   TypeName parseTypeName(bool inExpression) {
     TypeName realType = _parseTypeName(inExpression);
     // If this is followed by a generic method type comment, allow the comment
@@ -5290,7 +5290,7 @@ class Parser {
     }
     if (_matchesKeyword(Keyword.EXTENDS)) {
       Token keyword = getAndAdvance();
-      TypeAnnotation bound = parseTypeAnnotation(false);
+      TypeAnnotation bound = parseTypeNotVoid(false);
       return astFactory.typeParameter(commentAndMetadata.comment,
           commentAndMetadata.metadata, name, keyword, bound);
     }
@@ -5620,29 +5620,6 @@ class Parser {
     return null;
   }
 
-  /**
-   * Parse a return type, starting at the [startToken], without actually
-   * creating a return type or changing the current token. Return the token
-   * following the return type that was parsed, or `null` if the given token is
-   * not the first token in a valid return type.
-   *
-   * This method must be kept in sync with [parseReturnType].
-   *
-   *     returnType ::=
-   *         'void'
-   *       | type
-   */
-  Token skipReturnType(Token startToken) {
-    if (_tokenMatchesKeyword(startToken, Keyword.VOID)) {
-      if (_atGenericFunctionTypeAfterReturnType(_peek())) {
-        return skipTypeAnnotation(startToken);
-      }
-      return startToken.next;
-    } else {
-      return skipTypeAnnotation(startToken);
-    }
-  }
-
   /**
    * Parse a simple identifier, starting at the [startToken], without actually
    * creating a simple identifier or changing the current token. Return the
@@ -5701,12 +5678,10 @@ class Parser {
   Token skipTypeAnnotation(Token startToken) {
     Token next = null;
     if (_atGenericFunctionTypeAfterReturnType(startToken)) {
+      // Generic function type with no return type.
       next = skipGenericFunctionTypeAfterReturnType(startToken);
-    } else if (startToken.keyword == Keyword.VOID &&
-        _atGenericFunctionTypeAfterReturnType(startToken.next)) {
-      next = startToken.next;
     } else {
-      next = skipTypeName(startToken);
+      next = skipTypeWithoutFunction(startToken);
     }
     while (next != null && _atGenericFunctionTypeAfterReturnType(next)) {
       next = skipGenericFunctionTypeAfterReturnType(next);
@@ -5714,6 +5689,22 @@ class Parser {
     return next;
   }
 
+  /**
+   * Parse a typeWithoutFunction, starting at the [startToken], without actually
+   * creating a TypeAnnotation or changing the current token. Return the token
+   * following the typeWithoutFunction that was parsed, or `null` if the given
+   * token is not the first token in a valid typeWithoutFunction.
+   *
+   * This method must be kept in sync with [parseTypeWithoutFunction].
+   */
+  Token skipTypeWithoutFunction(Token startToken) {
+    if (startToken.keyword == Keyword.VOID) {
+      return startToken.next;
+    } else {
+      return skipTypeName(startToken);
+    }
+  }
+
   /**
    * Parse a list of type arguments, starting at the [startToken], without
    * actually creating a type argument list or changing the current token.
@@ -5735,7 +5726,7 @@ class Parser {
         !_injectGenericCommentTypeList()) {
       return null;
     }
-    token = skipTypeName(token.next);
+    token = skipTypeAnnotation(token.next);
     if (token == null) {
       // If the start token '<' is followed by '>'
       // then assume this should be type argument list but is missing a type
@@ -5746,7 +5737,7 @@ class Parser {
       return null;
     }
     while (_tokenMatches(token, TokenType.COMMA)) {
-      token = skipTypeName(token.next);
+      token = skipTypeAnnotation(token.next);
       if (token == null) {
         return null;
       }
@@ -5933,7 +5924,7 @@ class Parser {
         // This looks like the start of a function
         return true;
       }
-      Token token = skipReturnType(_currentToken);
+      Token token = skipTypeAnnotation(_currentToken);
       if (token == null) {
         return false;
       }
@@ -6321,7 +6312,7 @@ class Parser {
    * name that is followed by a variable or field formal parameter.
    */
   bool _isTypedIdentifier(Token startToken) {
-    Token token = skipReturnType(startToken);
+    Token token = skipTypeAnnotation(startToken);
     if (token == null) {
       return false;
     } else if (_tokenMatchesIdentifier(token)) {
@@ -6330,10 +6321,6 @@ class Parser {
         _tokenMatches(token.next, TokenType.PERIOD) &&
         _tokenMatchesIdentifier(token.next.next)) {
       return true;
-    } else if (_tokenMatchesKeyword(startToken, Keyword.VOID)) {
-      // The keyword 'void' isn't a valid identifier, so it should be assumed to
-      // be a type name.
-      return true;
     } else if (startToken.next != token &&
         !_tokenMatches(token, TokenType.OPEN_PAREN)) {
       // The type is more than a simple identifier, so it should be assumed to
@@ -7023,7 +7010,7 @@ class Parser {
       CommentAndMetadata commentAndMetadata, Token keyword) {
     TypeAnnotation returnType = null;
     if (hasReturnTypeInTypeAlias) {
-      returnType = parseReturnType(false);
+      returnType = parseTypeAnnotation(false);
     }
     SimpleIdentifier name = parseSimpleIdentifier(isDeclaration: true);
     TypeParameterList typeParameters = null;
@@ -7338,7 +7325,7 @@ class Parser {
           // type.
           return null;
         }
-        return parseReturnType(false);
+        return parseTypeAnnotation(false);
       }
       Token next2 = next.next;
       Token next3 = next2.next;
@@ -7346,7 +7333,7 @@ class Parser {
           _tokenMatchesIdentifier(next2) &&
           (_tokenMatchesIdentifier(next3) ||
               _tokenMatches(next3, TokenType.LT))) {
-        return parseReturnType(false);
+        return parseTypeAnnotation(false);
       }
     }
     return null;
@@ -7891,7 +7878,7 @@ class Parser {
               (_tokenMatchesIdentifier(next.next.next) ||
                   _tokenMatches(next.next.next, TokenType.LT) ||
                   _tokenMatchesKeyword(next.next.next, Keyword.THIS)))) {
-        return skipReturnType(startToken);
+        return skipTypeAnnotation(startToken);
       }
     }
     return null;