Fix isValidMethodTypeArguments

Change-Id: I3c4bb8dc981c285b8ecfad7dcd7dc849ed1bda7b
Reviewed-on: https://dart-review.googlesource.com/52920
Commit-Queue: Dan Rubel <danrubel@google.com>
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>

pkg/analyzer/test/generated/parser_test.dart

@@ -13923,6 +13923,23 @@ class C {}
     expect(creation.argumentList, isNotNull);
   }
 
+  void test_parseInstanceCreation_noKeyword_varInit() {
+    enableOptionalNewAndConst = true;
+    createParser('''
+class C<T, S> {}
+void main() {final c = C<int, int Function(String)>();}
+''');
+    CompilationUnit unit = parser.parseCompilationUnit2();
+    expect(unit, isNotNull);
+    FunctionDeclaration f = unit.declarations[1];
+    BlockFunctionBody body = f.functionExpression.body;
+    VariableDeclarationStatement statement = body.block.statements[0];
+    VariableDeclaration variable = statement.variables.variables[0];
+    MethodInvocation creation = variable.initializer;
+    expect(creation.methodName.name, 'C');
+    expect(creation.typeArguments.toSource(), '<int, int Function(String)>');
+  }
+
   void test_parseLibraryIdentifier_invalid() {
     parseCompilationUnit('library <myLibId>;',
         errors: usingFastaParser

pkg/front_end/lib/src/fasta/parser/parser.dart

@@ -34,8 +34,6 @@ import '../scanner/token_constants.dart'
         EOF_TOKEN,
         EQ_TOKEN,
         FUNCTION_TOKEN,
-        GT_GT_TOKEN,
-        GT_TOKEN,
         HASH_TOKEN,
         HEXADECIMAL_TOKEN,
         IDENTIFIER_TOKEN,
@@ -45,7 +43,6 @@ import '../scanner/token_constants.dart'
         OPEN_CURLY_BRACKET_TOKEN,
         OPEN_PAREN_TOKEN,
         OPEN_SQUARE_BRACKET_TOKEN,
-        PERIOD_TOKEN,
         SEMICOLON_TOKEN,
         STRING_INTERPOLATION_IDENTIFIER_TOKEN,
         STRING_INTERPOLATION_TOKEN,
@@ -94,6 +91,8 @@ import 'type_info.dart'
         isValidTypeReference,
         noType;
 
+import 'type_info_impl.dart' show skipTypeVariables;
+
 import 'util.dart' show optional;
 
 /// An event generating parser of Dart programs. This parser expects all tokens
@@ -1506,76 +1505,14 @@ class Parser {
   /// arguments in generic method invocations can be recognized, and as few as
   /// possible other constructs will pass (e.g., 'a < C, D > 3').
   bool isValidMethodTypeArguments(Token token) {
-    Token Function(Token token) tryParseType;
-
-    /// Returns token after match if [token] matches '<' type (',' type)* '>'
-    /// '(', and otherwise returns null. Does not produce listener events. With
-    /// respect to the final '(', please see the description of
-    /// [isValidMethodTypeArguments].
-    Token tryParseMethodTypeArguments(Token token) {
-      if (!identical(token.kind, LT_TOKEN)) return null;
-      Token endToken = token.endGroup;
-      if (endToken == null ||
-          !identical(endToken.next.kind, OPEN_PAREN_TOKEN)) {
-        return null;
+    // TODO(danrubel): Replace call with a call to computeTypeVar.
+    if (optional('<', token)) {
+      Token endGroup = skipTypeVariables(token);
+      if (endGroup != null && optional('(', endGroup.next)) {
+        return true;
       }
-      token = tryParseType(token.next);
-      while (token != null && identical(token.kind, COMMA_TOKEN)) {
-        token = tryParseType(token.next);
-      }
-      if (token == null || !identical(token.kind, GT_TOKEN)) return null;
-      return token.next;
     }
-
-    /// Returns token after match if [token] matches identifier ('.'
-    /// identifier)?, and otherwise returns null. Does not produce listener
-    /// events.
-    Token tryParseQualified(Token token) {
-      if (!isValidTypeReference(token)) return null;
-      token = token.next;
-      if (!identical(token.kind, PERIOD_TOKEN)) return token;
-      token = token.next;
-      if (!identical(token.kind, IDENTIFIER_TOKEN)) return null;
-      return token.next;
-    }
-
-    /// Returns token after match if [token] matches '<' type (',' type)* '>',
-    /// and otherwise returns null. Does not produce listener events. The final
-    /// '>' may be the first character in a '>>' token, in which case a
-    /// synthetic '>' token is created and returned, representing the second
-    /// '>' in the '>>' token.
-    Token tryParseNestedTypeArguments(Token token) {
-      if (!identical(token.kind, LT_TOKEN)) return null;
-      // If the initial '<' matches the first '>' in a '>>' token, we will have
-      // `token.endGroup == null`, so we cannot rely on `token.endGroup == null`
-      // to imply that the match must fail. Hence no `token.endGroup == null`
-      // test here.
-      token = tryParseType(token.next);
-      while (token != null && identical(token.kind, COMMA_TOKEN)) {
-        token = tryParseType(token.next);
-      }
-      if (token == null) return null;
-      if (identical(token.kind, GT_TOKEN)) return token.next;
-      if (!identical(token.kind, GT_GT_TOKEN)) return null;
-      // [token] is '>>' of which the final '>' that we are parsing is the first
-      // character. In order to keep the parsing process on track we must return
-      // a synthetic '>' corresponding to the second character of that '>>'.
-      Token syntheticToken = new Token(TokenType.GT, token.charOffset + 1);
-      syntheticToken.next = token.next;
-      return syntheticToken;
-    }
-
-    /// Returns token after match if [token] matches typeName typeArguments?,
-    /// and otherwise returns null. Does not produce listener events.
-    tryParseType = (Token token) {
-      token = tryParseQualified(token);
-      if (token == null) return null;
-      Token tokenAfterQualified = token;
-      token = tryParseNestedTypeArguments(token);
-      return token == null ? tokenAfterQualified : token;
-    };
-
-    return tryParseMethodTypeArguments(token) != null;
+    return false;
   }
 
   /// ```

tests/language_2/language_2_dart2js.status

@@ -282,7 +282,7 @@ covariance_type_parameter_test/01: Crash # NoSuchMethodError: The method 'hasSub
 covariance_type_parameter_test/02: Crash # NoSuchMethodError: The method 'hasSubclass' was called on null.
 covariance_type_parameter_test/03: Crash # NoSuchMethodError: The method 'hasSubclass' was called on null.
 covariant_override/runtime_check_test: RuntimeError
-covariant_subtyping_test: CompileTimeError
+covariant_subtyping_test: RuntimeError
 cyclic_constructor_test/01: Crash # Stack Overflow
 deferred_constraints_constants_test/default_argument2: Crash # Unsupported operation: KernelDeferredLoadTask.addMirrorElementsForLibrary
 deferred_constraints_constants_test/none: Crash # Unsupported operation: KernelDeferredLoadTask.addMirrorElementsForLibrary
@@ -1092,7 +1092,7 @@ covariance_type_parameter_test/01: RuntimeError
 covariance_type_parameter_test/02: RuntimeError
 covariance_type_parameter_test/03: RuntimeError
 covariant_override/tear_off_type_test: RuntimeError
-covariant_subtyping_test: CompileTimeError
+covariant_subtyping_test: RuntimeError
 cyclic_constructor_test/01: Crash # Issue 30856
 cyclic_type_test/00: RuntimeError
 cyclic_type_test/02: RuntimeError
@@ -1713,7 +1713,7 @@ covariance_type_parameter_test/01: RuntimeError
 covariance_type_parameter_test/02: RuntimeError
 covariance_type_parameter_test/03: RuntimeError
 covariant_override/tear_off_type_test: RuntimeError
-covariant_subtyping_test: CompileTimeError
+covariant_subtyping_test: RuntimeError
 cyclic_constructor_test/01: Crash # Issue 30856
 cyclic_type_variable_test/01: MissingCompileTimeError
 cyclic_type_variable_test/02: MissingCompileTimeError
@@ -2189,6 +2189,7 @@ wrong_number_type_arguments_test/none: Pass
 
 [ $compiler == dart2js && $fasta && $strong ]
 const_constructor3_test/04: MissingCompileTimeError # OK - Subtype check uses JS number semantics.
+covariant_subtyping_test: Crash
 ct_const_test: RuntimeError
 
 [ $compiler == dart2js && $fasta && !$strong ]

tests/language_2/language_2_dartdevc.status

@@ -348,7 +348,7 @@ constants_test/05: MissingCompileTimeError
 constructor_redirect1_negative_test/01: MissingCompileTimeError
 constructor_redirect2_negative_test: MissingCompileTimeError
 constructor_redirect_test/01: MissingCompileTimeError
-covariant_subtyping_test: CompileTimeError
+covariant_subtyping_test: RuntimeError
 cyclic_constructor_test/01: MissingCompileTimeError
 cyclic_type_variable_test/01: MissingCompileTimeError
 cyclic_type_variable_test/02: MissingCompileTimeError

tests/language_2/language_2_kernel.status

@@ -82,7 +82,6 @@ const_types_test/39: MissingCompileTimeError
 constructor_redirect1_negative_test/01: MissingCompileTimeError
 constructor_redirect2_negative_test: MissingCompileTimeError
 constructor_redirect_test/01: MissingCompileTimeError # Fasta bug: Initializer refers to this.
-covariant_subtyping_test: CompileTimeError
 cyclic_constructor_test/01: MissingCompileTimeError # Fasta bug: Cyclic constructor redirection.
 cyclic_type_variable_test/01: MissingCompileTimeError
 cyclic_type_variable_test/02: MissingCompileTimeError
@@ -572,6 +571,7 @@ const_nested_test: RuntimeError # KernelVM bug: Constant evaluation.
 const_string_test: RuntimeError
 constructor12_test: RuntimeError
 constructor3_test: Fail, OK, Pass
+covariant_subtyping_test: RuntimeError
 ct_const2_test: Pass, Crash # Flaky
 ct_const_test: RuntimeError
 cyclic_type2_test: RuntimeError, CompileTimeError

tests/language_2/language_2_precompiled.status

@@ -247,7 +247,7 @@ covariant_override/runtime_check_test: RuntimeError
 covariant_subtyping_tearoff1_test: RuntimeError
 covariant_subtyping_tearoff2_test: RuntimeError
 covariant_subtyping_tearoff3_test: RuntimeError
-covariant_subtyping_test: CompileTimeError
+covariant_subtyping_test: RuntimeError
 covariant_subtyping_unsafe_call1_test: RuntimeError
 covariant_subtyping_unsafe_call2_test: RuntimeError
 covariant_subtyping_unsafe_call3_test: RuntimeError