Fix propagated argument element bug. This fixes #25040.

pkg/analyzer/test/generated/resolver_test.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library engine.resolver_test;
 
 import 'dart:collection';
 
 import 'package:analyzer/src/context/context.dart' as newContext;
 import 'package:analyzer/src/generated/ast.dart';
@@ skipping 12118 matching lines @@
     computeLibrarySourceErrors(source);
     assertErrors(source, [StaticTypeWarningCode.UNDEFINED_OPERATOR]);
   }
 }
 
 /**
  * Strong mode static analyzer end to end tests
  */
 @reflectiveTest
 class StrongModeStaticTypeAnalyzer2Test extends _StaticTypeAnalyzer2TestShared {
+  void fail_genericMethod_nested() {
+    // TODO(jmesserly): this test currently fails because we incorrectly capture
+    // S in FunctionTypeImpl.substitute. We should probably rename free
+    // variables during substitution to avoid it.
+    _resolveTestUnit(r'''
+class C<T> {
+  /*=T*/ f/*<S>*/(/*=S*/ x) {
+    new C<S>().f/*<int>*/(3);
+    return null;
+  }
+}
+''');
+    SimpleIdentifier f = _findIdentifier('f/*<int>*/(3);');
+    expect(f.staticType.toString(), '(int) → S');
+  }
+
   void setUp() {
     AnalysisOptionsImpl options = new AnalysisOptionsImpl();
     options.strongMode = true;
     resetWithOptions(options);
   }
 
   void test_dynamicObjectGetter_hashCode() {
     String code = r'''
 main() {
   dynamic a = null;
@@ skipping 63 matching lines @@
     expect(e.type.toString(), '(E) → List<T>');
 
     SimpleIdentifier c = _findIdentifier('cOfString');
     FunctionType ft = (c.staticType as InterfaceType).getMethod('f').type;
     expect(ft.toString(), '(String) → List<T>');
     DartType t = e.typeParameters[0].type;
     ft = ft.substitute2([typeProvider.intType], [t]);
     expect(ft.toString(), '(String) → List<int>');
   }
 
-  void fail_genericMethod_nested() {
-    // TODO(jmesserly): this test currently fails because we incorrectly capture
-    // S in FunctionTypeImpl.substitute. We should probably rename free
-    // variables during substitution to avoid it.
-    _resolveTestUnit(r'''
-class C<T> {
-  /*=T*/ f/*<S>*/(/*=S*/ x) {
-    new C<S>().f/*<int>*/(3);
-    return null;
-  }
-}
-''');
-    SimpleIdentifier f = _findIdentifier('f/*<int>*/(3);');
-    expect(f.staticType.toString(), '(int) → S');
-  }
-
   void test_genericMethod_functionTypedParameter() {
     if (!AnalysisEngine.instance.useTaskModel) {
       return;
     }
     _resolveTestUnit(r'''
 class C<E> {
   List/*<T>*/ f/*<T>*/(/*=T*/ f(E e)) => null;
 }
 main() {
   C<String> cOfString;
@@ skipping 23 matching lines @@
 ''';
     _resolveTestUnit(code);
 
     SimpleIdentifier identifier = _findIdentifier('foo');
     VariableDeclaration declaration =
         identifier.getAncestor((node) => node is VariableDeclaration);
     expect(declaration.initializer.staticType.name, 'double');
     expect(declaration.initializer.propagatedType, isNull);
   }
 
+  void test_pseudoGeneric_max_doubleDouble_prefixed() {
+    String code = r'''
+import 'dart:math' as math;
+main() {
+  var foo = math.max(1.0, 2.0);
+}
+''';
+    _resolveTestUnit(code);
+
+    SimpleIdentifier identifier = _findIdentifier('foo');
+    VariableDeclaration declaration =
+        identifier.getAncestor((node) => node is VariableDeclaration);
+    expect(declaration.initializer.staticType.name, 'double');
+    expect(declaration.initializer.propagatedType, isNull);
+  }
+
   void test_pseudoGeneric_max_doubleInt() {
     String code = r'''
 import 'dart:math';
 main() {
   var foo = max(1.0, 2);
 }
 ''';
     _resolveTestUnit(code);
 
     SimpleIdentifier identifier = _findIdentifier('foo');
@@ skipping 47 matching lines @@
     _resolveTestUnit(code);
 
     SimpleIdentifier identifier = _findIdentifier('foo');
     VariableDeclaration declaration =
         identifier.getAncestor((node) => node is VariableDeclaration);
 
     expect(declaration.initializer.staticType.toString(), "Future<String>");
     expect(declaration.initializer.propagatedType, isNull);
   }
 
+  void test_pseudoGeneric_then_prefixed() {
+    String code = r'''
+import 'dart:async' as async;
+String toString(int x) => x.toString();
+main() {
+  async.Future<int> bar = null;
+  var foo = bar.then(toString);
+}
+''';
+    _resolveTestUnit(code);
+
+    SimpleIdentifier identifier = _findIdentifier('foo');
+    VariableDeclaration declaration =
+        identifier.getAncestor((node) => node is VariableDeclaration);
+
+    expect(declaration.initializer.staticType.toString(), "Future<String>");
+    expect(declaration.initializer.propagatedType, isNull);
+  }
+
   void test_ternaryOperator_null_left() {
     String code = r'''
 main() {
   var foo = (true) ? null : 3;
 }
 ''';
     _resolveTestUnit(code);
 
     SimpleIdentifier identifier = _findIdentifier('foo');
     VariableDeclaration declaration =
@@ skipping 453 matching lines @@
   }
 
   void test_getType_noScope() {
     TypeOverrideManager manager = new TypeOverrideManager();
     expect(manager.getType(ElementFactory.localVariableElement2("v")), isNull);
   }
 }
 
 @reflectiveTest
 class TypePropagationTest extends ResolverTestCase {
+  void test_invocation_target_prefixed() {
+    addNamedSource(
+        '/helper.dart',
+        '''
+library helper;
+int max(int x, int y) => 0;
+''');
+    String code = '''
+import 'helper.dart' as helper;
+main() {
+  helper.max(10, 10); // marker
+}''';
+    SimpleIdentifier methodName =
+        _findMarkedIdentifier(code, "(10, 10); // marker");
+    MethodInvocation methodInvoke = methodName.parent;
+    expect(methodInvoke.methodName.staticElement, isNotNull);
+    expect(methodInvoke.methodName.propagatedElement, isNull);
+  }
+
   void fail_mergePropagatedTypesAtJoinPoint_1() {
     // https://code.google.com/p/dart/issues/detail?id=19929
     _assertTypeOfMarkedExpression(
         r'''
 f1(x) {
   var y = [];
   if (x) {
     y = 0;
   } else {
     y = '';
@@ skipping 2393 matching lines @@
 
   void _resolveTestUnit(String code) {
     testCode = code;
     testSource = addSource(testCode);
     LibraryElement library = resolve2(testSource);
     assertNoErrors(testSource);
     verify([testSource]);
     testUnit = resolveCompilationUnit(testSource, library);
   }
 }