Serialize any MethodInvocation as possible const.

Bug: dart-lang/sdk#32823
Change-Id: I0be8d25cf9d5ac16aacb693c4730ddaba3ccad5a
Reviewed-on: https://dart-review.googlesource.com/50160
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>

Author: scheglov

pkg/analyzer/lib/src/dart/analysis/driver.dart

@@ -95,7 +95,7 @@ class AnalysisDriver implements AnalysisDriverGeneric {
   /**
    * The version of data format, should be incremented on every format change.
    */
-  static const int DATA_VERSION = 55;
+  static const int DATA_VERSION = 56;
 
   /**
    * The number of exception contexts allowed to write. Once this field is

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

@@ -18,6 +18,7 @@ import 'package:analyzer/error/listener.dart';
 import 'package:analyzer/exception/exception.dart';
 import 'package:analyzer/src/dart/ast/ast.dart';
 import 'package:analyzer/src/dart/ast/ast_factory.dart';
+import 'package:analyzer/src/dart/ast/token.dart';
 import 'package:analyzer/src/dart/ast/utilities.dart';
 import 'package:analyzer/src/dart/element/element.dart';
 import 'package:analyzer/src/dart/element/member.dart' show ConstructorMember;
@@ -44,12 +45,14 @@ export 'package:analyzer/src/generated/type_system.dart';
  * feature.
  */
 class AstRewriteVisitor extends ScopedVisitor {
+  final bool addConstKeyword;
+
   /**
    * Initialize a newly created visitor.
    */
   AstRewriteVisitor(LibraryElement definingLibrary, Source source,
       TypeProvider typeProvider, AnalysisErrorListener errorListener,
-      {Scope nameScope})
+      {Scope nameScope, this.addConstKeyword: false})
       : super(definingLibrary, source, typeProvider, errorListener,
             nameScope: nameScope);
 
@@ -77,7 +80,7 @@ class AstRewriteVisitor extends ScopedVisitor {
         TypeName typeName = astFactory.typeName(methodName, node.typeArguments);
         InstanceCreationExpression instanceCreationExpression =
             astFactory.instanceCreationExpression(
-                null,
+                _getKeyword(node),
                 astFactory.constructorName(typeName, null, null),
                 node.argumentList);
         DartType type = _getType(element, node.typeArguments);
@@ -100,7 +103,7 @@ class AstRewriteVisitor extends ScopedVisitor {
           TypeName typeName = astFactory.typeName(target, node.typeArguments);
           InstanceCreationExpression instanceCreationExpression =
               astFactory.instanceCreationExpression(
-                  null,
+                  _getKeyword(node),
                   astFactory.constructorName(
                       typeName, node.operator, methodName),
                   node.argumentList);
@@ -124,7 +127,7 @@ class AstRewriteVisitor extends ScopedVisitor {
               node.typeArguments);
           InstanceCreationExpression instanceCreationExpression =
               astFactory.instanceCreationExpression(
-                  null,
+                  _getKeyword(node),
                   astFactory.constructorName(typeName, null, null),
                   node.argumentList);
           DartType type = _getType(prefixedElement, node.typeArguments);
@@ -145,7 +148,7 @@ class AstRewriteVisitor extends ScopedVisitor {
             TypeName typeName = astFactory.typeName(target, node.typeArguments);
             InstanceCreationExpression instanceCreationExpression =
                 astFactory.instanceCreationExpression(
-                    null,
+                    _getKeyword(node),
                     astFactory.constructorName(
                         typeName, node.operator, methodName),
                     node.argumentList);
@@ -161,6 +164,16 @@ class AstRewriteVisitor extends ScopedVisitor {
     return null;
   }
 
+  /**
+   * Return the token that should be used in the [InstanceCreationExpression]
+   * that corresponds to the given invocation [node].
+   */
+  Token _getKeyword(MethodInvocation node) {
+    return addConstKeyword
+        ? new KeywordToken(Keyword.CONST, node.offset)
+        : null;
+  }
+
   /**
    * Return the type of the given class [element] after substituting any type
    * arguments from the list of [typeArguments] for the class' type parameters.

pkg/analyzer/lib/src/summary/resynthesize.dart

@@ -7,8 +7,10 @@ library summary_resynthesizer;
 import 'dart:collection';
 
 import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/ast/standard_ast_factory.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
+import 'package:analyzer/error/listener.dart';
 import 'package:analyzer/src/dart/element/element.dart';
 import 'package:analyzer/src/dart/element/handle.dart';
 import 'package:analyzer/src/dart/element/member.dart';
@@ -1118,6 +1120,11 @@ class _UnitResynthesizer extends UnitResynthesizer with UnitResynthesizerMixin {
    */
   CompilationUnitElementImpl unit;
 
+  /**
+   * The visitor to rewrite implicit `new` and `const`.
+   */
+  AstRewriteVisitor astRewriteVisitor;
+
   /**
    * Map from slot id to the corresponding [EntityRef] object for linked types
    * (i.e. propagated and inferred types).
@@ -1561,7 +1568,18 @@ class _UnitResynthesizer extends UnitResynthesizer with UnitResynthesizerMixin {
   }
 
   Expression _buildConstExpression(ElementImpl context, UnlinkedExpr uc) {
-    return new ExprBuilder(this, context, uc).build();
+    var expression = new ExprBuilder(this, context, uc).build();
+
+    if (expression != null && context.context.analysisOptions.previewDart2) {
+      astRewriteVisitor ??= new AstRewriteVisitor(libraryResynthesizer.library,
+          unit.source, typeProvider, AnalysisErrorListener.NULL_LISTENER,
+          addConstKeyword: true);
+      var container = astFactory.expressionStatement(expression, null);
+      expression.accept(astRewriteVisitor);
+      expression = container.expression;
+    }
+
+    return expression;
   }
 
   /**

pkg/analyzer/lib/src/summary/summarize_const_expr.dart

@@ -595,10 +595,6 @@ abstract class AbstractConstExprSerializer {
   }
 
   void _serializeMethodInvocation(MethodInvocation invocation) {
-    if (invocation.target != null ||
-        invocation.methodName.name != 'identical') {
-      isValidConst = false;
-    }
     Expression target = invocation.target;
     SimpleIdentifier methodName = invocation.methodName;
     ArgumentList argumentList = invocation.argumentList;

pkg/analyzer/test/src/dart/analysis/driver_test.dart

@@ -344,6 +344,12 @@ class AnalysisDriverSchedulerTest {
 
 @reflectiveTest
 class AnalysisDriverTest extends BaseAnalysisDriverTest {
+  void configurePreviewDart2() {
+    driver.configure(
+        analysisOptions: new AnalysisOptionsImpl.from(driver.analysisOptions)
+          ..previewDart2 = true);
+  }
+
   test_addedFiles() async {
     var a = _p('/test/lib/a.dart');
     var b = _p('/test/lib/b.dart');
@@ -1002,6 +1008,63 @@ class B {}
     expect(x.constantValue, isNotNull);
   }
 
+  test_const_implicitCreation() async {
+    configurePreviewDart2();
+
+    var a = _p('/test/bin/a.dart');
+    var b = _p('/test/bin/b.dart');
+    provider.newFile(a, r'''
+class C {
+  const C();
+  static const C WARNING = C();
+}
+''');
+    provider.newFile(b, r'''
+import 'a.dart';
+
+class D {
+  const D();
+  static const D WARNING = D();
+}
+
+const c = C.WARNING;
+const d = D.WARNING;
+''');
+    AnalysisResult result = await driver.getResult(b);
+    expect(result.errors, isEmpty);
+  }
+
+  test_const_implicitCreation_rewrite() async {
+    configurePreviewDart2();
+
+    var a = _p('/test/bin/a.dart');
+    var b = _p('/test/bin/b.dart');
+    provider.newFile(a, r'''
+class A {
+  const A();
+}
+
+class B {
+  final A a;
+  const B(this.a);
+}
+
+class C {
+  const b = B(A());
+  const C();
+}
+''');
+    provider.newFile(b, r'''
+import 'a.dart';
+
+main() {
+  const C();
+}
+''');
+    AnalysisResult result = await driver.getResult(b);
+    expect(result.errors, isEmpty);
+  }
+
   test_const_implicitSuperConstructorInvocation() async {
     addTestFile('''
 class Base {}

pkg/analyzer/test/src/summary/resynthesize_common.dart

@@ -2526,7 +2526,7 @@ class C {
   }
 
   test_const_invalid_field_const() async {
-    variablesWithNotConstInitializers.add('f');
+    shouldCompareLibraryElements = false;
     var library = await checkLibrary(r'''
 class C {
   static const f = 1 + foo();
@@ -2545,14 +2545,16 @@ int foo() {}
     } else if (isStrongMode) {
       checkElementText(library, r'''
 class C {
-  static const int f;
+  static const int f = 1 +
+        foo/*location: test.dart;foo*/();
 }
 int foo() {}
 ''');
     } else {
       checkElementText(library, r'''
 class C {
-  static const dynamic f;
+  static const dynamic f = 1 +
+        foo/*location: test.dart;foo*/();
 }
 int foo() {}
 ''');
@@ -2594,7 +2596,7 @@ const int x = 0;
   }
 
   test_const_invalid_topLevel() async {
-    variablesWithNotConstInitializers.add('v');
+    shouldCompareLibraryElements = false;
     var library = await checkLibrary(r'''
 const v = 1 + foo();
 int foo() => 42;
@@ -2608,12 +2610,14 @@ int foo() {}
 ''');
     } else if (isStrongMode) {
       checkElementText(library, r'''
-const int v;
+const int v = 1 +
+        foo/*location: test.dart;foo*/();
 int foo() {}
 ''');
     } else {
       checkElementText(library, r'''
-const dynamic v;
+const dynamic v = 1 +
+        foo/*location: test.dart;foo*/();
 int foo() {}
 ''');
     }
@@ -4566,17 +4570,16 @@ class C {
   }
 
   test_constructor_initializers_field_notConst() async {
-    variablesWithNotConstInitializers.add('x');
+    shouldCompareLibraryElements = false;
     var library = await checkLibrary('''
 class C {
   final x;
   const C() : x = foo();
 }
 int foo() => 42;
 ''', allowErrors: true);
-    if (isSharedFrontEnd) {
-      // It is OK to keep non-constant initializers.
-      checkElementText(library, r'''
+    // It is OK to keep non-constant initializers.
+    checkElementText(library, r'''
 class C {
   final dynamic x;
   const C() :
@@ -4585,16 +4588,6 @@ class C {
 }
 int foo() {}
 ''');
-    } else {
-      checkElementText(library, r'''
-class C {
-  final dynamic x;
-  const C() :
-        x/*location: test.dart;C;x*/ = <null>;
-}
-int foo() {}
-''');
-    }
   }
 
   test_constructor_initializers_field_withParameter() async {