Serialize and resynthesize unresolved identifiers.

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

 // Copyright (c) 2015, 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 test.src.serialization.elements_test;
 
 import 'dart:convert';
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/element/element.dart';
@@ skipping 493 matching lines @@
     expect(resynthesized.compilationUnit.location,
         original.compilationUnit.location,
         reason: desc);
     expect(resynthesized.annotationAst, isNotNull, reason: desc);
     compareConstAsts(resynthesized.annotationAst, original.annotationAst, desc);
   }
 
   void compareElements(Element resynthesized, Element original, String desc) {
     ElementImpl rImpl = getActualElement(resynthesized, desc);
     ElementImpl oImpl = getActualElement(original, desc);
+    if (oImpl == null && rImpl == null) {
+      return;
+    }
+    expect(original, isNotNull);
+    expect(resynthesized, isNotNull);
     expect(rImpl.runtimeType, oImpl.runtimeType);
-    expect(resynthesized, isNotNull);
     expect(resynthesized.kind, original.kind);
     expect(resynthesized.location, original.location, reason: desc);
     expect(resynthesized.name, original.name);
     expect(resynthesized.nameOffset, original.nameOffset, reason: desc);
     expect(resynthesized.documentationComment, original.documentationComment,
         reason: desc);
     expect(resynthesized.docRange, original.docRange, reason: desc);
     compareMetadata(resynthesized.metadata, original.metadata, desc);
     // Modifiers are a pain to test via handles.  So just test them via the
     // actual element.
@@ skipping 398 matching lines @@
         unlinkedSummaries,
         linkedSummaries,
         options.strongMode);
   }
 
   fail_library_hasExtUri() {
     checkLibrary('import "dart-ext:doesNotExist.dart";');
   }
 
   ElementImpl getActualElement(Element element, String desc) {
-    if (element is ElementImpl) {
+    if (element == null) {
+      return null;
+    } else if (element is ElementImpl) {
       return element;
     } else if (element is ElementHandle) {
       Element actualElement = element.actualElement;
       // A handle should never point to a member, because if it did, then
       // "is Member" checks on the handle would produce the wrong result.
       expect(actualElement, isNot(new isInstanceOf<Member>()), reason: desc);
       return getActualElement(actualElement, desc);
     } else if (element is Member) {
       return getActualElement(element.baseElement, desc);
     } else {
@@ skipping 844 matching lines @@
 typedef F(int a, String b);
 ''');
     checkLibrary(r'''
 import 'a.dart' as p;
 const vClass = p.C;
 const vEnum = p.E;
 const vFunctionTypeAlias = p.F;
 ''');
   }
 
+  test_const_reference_unresolved_prefix0() {
+    checkLibrary(
+        r'''
+const V = foo;
+''',
+        allowErrors: true);
+  }
+
+  test_const_reference_unresolved_prefix1() {
+    checkLibrary(
+        r'''
+class C {}
+const v = C.foo;
+''',
+        allowErrors: true);
+  }
+
+  test_const_reference_unresolved_prefix2() {
+    addLibrarySource(
+        '/foo.dart',
+        '''
+class C {}
+''');
+    checkLibrary(
+        r'''
+import 'foo.dart' as p;
+const v = p.C.foo;
+''',
+        allowErrors: true);
+  }
+
   test_const_topLevel_binary() {
     checkLibrary(r'''
 const vEqual = 1 == 2;
 const vAnd = true && false;
 const vOr = false || true;
 const vBitXor = 1 ^ 2;
 const vBitAnd = 1 & 2;
 const vBitOr = 1 | 2;
 const vBitShiftLeft = 1 << 2;
 const vBitShiftRight = 1 >> 2;
@@ skipping 1698 matching lines @@
       fail('Unexpectedly tried to get unlinked summary for $uri');
     }
     return serializedUnit;
   }
 
   @override
   bool hasLibrarySummary(String uri) {
     return true;
   }
 }