Fine. Special case dynamic element reference in constants.

I think we don't need to store `dynamic` element references anywhere
else, at least yet.

Change-Id: Icd8b033e4c3e29c7b3c1454fd3bd4a94fd076b54
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/422362
Reviewed-by: Paul Berry <[email protected]>
Commit-Queue: Konstantin Shcheglov <[email protected]>

Author: scheglov

pkg/analyzer/lib/src/fine/manifest_ast.dart

@@ -8,6 +8,7 @@ import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
 import 'package:analyzer/dart/element/element2.dart';
 import 'package:analyzer/src/dart/ast/ast.dart';
+import 'package:analyzer/src/dart/element/element.dart';
 import 'package:analyzer/src/fine/manifest_context.dart';
 import 'package:analyzer/src/summary2/data_reader.dart';
 import 'package:analyzer/src/summary2/data_writer.dart';
@@ -146,9 +147,6 @@ class ManifestNode {
 }
 
 class _ElementCollector extends ThrowingAstVisitor<void> {
-  static const int _nullIndex = 0;
-  static const int _importPrefixIndex = 1;
-
   final Map<Element2, int> map = Map.identity();
   final List<int> elementIndexList = [];
 
@@ -335,16 +333,26 @@ class _ElementCollector extends ThrowingAstVisitor<void> {
   void _addElement(Element2? element) {
     switch (element) {
       case null:
-        elementIndexList.add(_nullIndex);
+        elementIndexList.add(_ElementKind.null_.index);
+      case DynamicElementImpl2():
+        elementIndexList.add(_ElementKind.dynamic_.index);
       case PrefixElement2():
-        elementIndexList.add(_importPrefixIndex);
+        elementIndexList.add(_ElementKind.importPrefix.index);
       default:
-        var index = map[element] ??= 2 + map.length;
+        var base = _ElementKind.firstRegular.index;
+        var index = map[element] ??= base + map.length;
         elementIndexList.add(index);
     }
   }
 }
 
+enum _ElementKind {
+  null_,
+  dynamic_,
+  importPrefix,
+  firstRegular,
+}
+
 extension ListOfManifestNodeExtension on List<ManifestNode> {
   bool match(MatchContext context, List<AstNode> nodes) {
     if (nodes.length != length) {

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

@@ -17313,7 +17313,7 @@ const b = 0 + a;
           tokenLengthList: [1, 1, 1]
           elements
             [2] (dart:core, num, +) #M1
-          elementIndexList: [0, 2]
+          elementIndexList: [0, 3]
 ''',
       updatedCode: r'''
 const a = 1;
@@ -17336,7 +17336,7 @@ const b = 0 + a;
           elements
             [2] (package:test/test.dart, a) <null>
             [3] (dart:core, num, +) #M1
-          elementIndexList: [2, 3]
+          elementIndexList: [3, 4]
 ''',
     );
   }
@@ -17366,7 +17366,7 @@ const b = 1 + a;
           elements
             [2] (package:test/test.dart, a) <null>
             [3] (dart:core, num, +) #M2
-          elementIndexList: [2, 3]
+          elementIndexList: [3, 4]
 ''',
       updatedCode: r'''
 const b = 1 + a;
@@ -17382,7 +17382,7 @@ const b = 1 + a;
           tokenLengthList: [1, 1, 1]
           elements
             [2] (dart:core, num, +) #M2
-          elementIndexList: [0, 2]
+          elementIndexList: [0, 3]
 ''',
     );
   }
@@ -17561,6 +17561,34 @@ const a = A();
     );
   }
 
+  test_manifest_constInitializer_dynamicElement() async {
+    await _runLibraryManifestScenario(
+      initialCode: r'''
+const a = 0 as dynamic;
+const b = 0 as dynamic;
+''',
+      expectedInitialEvents: r'''
+[operation] linkLibraryCycle SDK
+[operation] linkLibraryCycle
+  package:test/test.dart
+    manifest
+      a: #M0
+      b: #M1
+''',
+      updatedCode: r'''
+const a = 0 as dynamic;
+const b = 0 as int;
+''',
+      expectedUpdatedEvents: r'''
+[operation] linkLibraryCycle
+  package:test/test.dart
+    manifest
+      a: #M0
+      b: #M2
+''',
+    );
+  }
+
   test_manifest_constInitializer_instanceCreation_argument() async {
     await _runLibraryManifestScenario(
       initialCode: r'''