Correctly handle constant fields when computing constness (take 2)

Change-Id: I03e78ff4a2ea18fa7362f159a07d6d035c59a4ae
Reviewed-on: https://dart-review.googlesource.com/50280
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Brian Wilkerson <brianwilkerson@google.com>

Author: bwilkerson

pkg/analyzer/lib/src/dart/ast/ast.dart

@@ -2766,20 +2766,23 @@ class ConstantAnalysisErrorListener extends AnalysisErrorListener {
 
   @override
   void onError(AnalysisError error) {
-    switch (error.errorCode) {
-      case CompileTimeErrorCode.CONST_EVAL_TYPE_BOOL:
-      case CompileTimeErrorCode.CONST_EVAL_TYPE_BOOL_NUM_STRING:
-      case CompileTimeErrorCode.CONST_EVAL_TYPE_INT:
-      case CompileTimeErrorCode.CONST_EVAL_TYPE_NUM:
-      case CompileTimeErrorCode.CONST_EVAL_THROWS_EXCEPTION:
-      case CompileTimeErrorCode.CONST_EVAL_THROWS_IDBZE:
-      case CompileTimeErrorCode.CONST_WITH_NON_CONSTANT_ARGUMENT:
-      case CompileTimeErrorCode.NON_CONSTANT_VALUE_IN_INITIALIZER:
-      case CompileTimeErrorCode
-          .CONST_CONSTRUCTOR_WITH_FIELD_INITIALIZED_BY_NON_CONST:
-      case CompileTimeErrorCode.INVALID_CONSTANT:
-      case CompileTimeErrorCode.MISSING_CONST_IN_LIST_LITERAL:
-        hasConstError = true;
+    ErrorCode errorCode = error.errorCode;
+    if (errorCode is CompileTimeErrorCode) {
+      switch (errorCode) {
+        case CompileTimeErrorCode.CONST_EVAL_TYPE_BOOL:
+        case CompileTimeErrorCode.CONST_EVAL_TYPE_BOOL_NUM_STRING:
+        case CompileTimeErrorCode.CONST_EVAL_TYPE_INT:
+        case CompileTimeErrorCode.CONST_EVAL_TYPE_NUM:
+        case CompileTimeErrorCode.CONST_EVAL_THROWS_EXCEPTION:
+        case CompileTimeErrorCode.CONST_EVAL_THROWS_IDBZE:
+        case CompileTimeErrorCode.CONST_WITH_NON_CONSTANT_ARGUMENT:
+        case CompileTimeErrorCode.NON_CONSTANT_VALUE_IN_INITIALIZER:
+        case CompileTimeErrorCode
+            .CONST_CONSTRUCTOR_WITH_FIELD_INITIALIZED_BY_NON_CONST:
+        case CompileTimeErrorCode.INVALID_CONSTANT:
+        case CompileTimeErrorCode.MISSING_CONST_IN_LIST_LITERAL:
+          hasConstError = true;
+      }
     }
   }
 }
@@ -6622,6 +6625,13 @@ class InstanceCreationExpressionImpl extends ExpressionImpl
             }
           }
         }
+      } else if (argument is Identifier) {
+        Element element = argument.bestElement;
+        if (element is PropertyAccessorElement && !element.variable.isConst) {
+          return false;
+        } else if (element is VariableElement && !element.isConst) {
+          return false;
+        }
       } else {
         return false;
       }

pkg/analyzer/lib/src/dart/constant/evaluation.dart

@@ -1633,6 +1633,7 @@ class ConstantVisitor extends UnifyingAstVisitor<DartObjectImpl> {
         element is PropertyAccessorElement ? element.variable : element;
     if (variableElement is VariableElementImpl) {
       evaluationEngine.validator.beforeGetEvaluationResult(variableElement);
+      variableElement.computeConstantValue();
       EvaluationResultImpl value = variableElement.evaluationResult;
       if (variableElement.isConst && value != null) {
         return value.value;

pkg/analyzer/lib/src/dart/constant/utilities.dart

@@ -69,8 +69,12 @@ class ConstantAstCloner extends AstCloner {
       InstanceCreationExpression node) {
     InstanceCreationExpression expression =
         super.visitInstanceCreationExpression(node);
-    if (previewDart2 && node.keyword == null && node.isConst) {
-      expression.keyword = new KeywordToken(Keyword.CONST, node.offset);
+    if (previewDart2 && node.keyword == null) {
+      if (node.isConst) {
+        expression.keyword = new KeywordToken(Keyword.CONST, node.offset);
+      } else {
+        expression.keyword = new KeywordToken(Keyword.NEW, node.offset);
+      }
     }
     expression.staticElement = node.staticElement;
     return expression;

pkg/analyzer/test/src/dart/ast/ast_test.dart

@@ -442,6 +442,8 @@ class InstanceCreationExpressionImplTest extends ResolverTestCase {
   String testSource;
   CompilationUnitImpl testUnit;
 
+  bool get enableNewAnalysisDriver => true;
+
   void assertIsConst(String snippet, bool isConst) {
     int index = testSource.indexOf(snippet);
     expect(index >= 0, isTrue);
@@ -462,6 +464,20 @@ class InstanceCreationExpressionImplTest extends ResolverTestCase {
     testUnit = await resolveSource2('/test.dart', source);
   }
 
+  void
+      test_isConst_notInContext_constructor_const_constParam_identifier() async {
+    enablePreviewDart2();
+    await resolve('''
+var v = C(C.a);
+class C {
+  static const C a = C.c();
+  const C(c);
+  const C.c();
+}
+''');
+    assertIsConst("C(C", true);
+  }
+
   void test_isConst_notInContext_constructor_const_constParam_named() async {
     enablePreviewDart2();
     await resolve('''