Revert "Revert "fix #26141, add support for type arguments to constants""

pkg/analyzer/test/src/task/strong/checker_test.dart

Index: pkg/analyzer/test/src/task/strong/checker_test.dart
diff --git a/pkg/analyzer/test/src/task/strong/checker_test.dart b/pkg/analyzer/test/src/task/strong/checker_test.dart
index 343a2aea64f2d536eccfd8990508c8cf5fb9ef5e..8bdd4ce38ac9f40e19f724610d096de008f93c69 100644
--- a/pkg/analyzer/test/src/task/strong/checker_test.dart
+++ b/pkg/analyzer/test/src/task/strong/checker_test.dart
@@ -2164,6 +2164,58 @@ dynamic y1 = (<dynamic>[])[0];
     check(implicitDynamic: false);
   }
 
+  void test_constantGenericTypeArg_infer() {
+    // Regression test for https://github.com/dart-lang/sdk/issues/26141
+    checkFile('''
+abstract class Equality<Q> {}
+abstract class EqualityBase<R> implements Equality<R> {
+  final C<R> c = /*info:INFERRED_TYPE_ALLOCATION*/const C();
+  const EqualityBase();
+}
+class DefaultEquality<S> extends EqualityBase<S> {
+  const DefaultEquality();
+}
+class SetEquality<T> implements Equality<T> {
+  final Equality<T> field = const DefaultEquality();
+  const SetEquality([Equality<T> inner = const DefaultEquality()]);
+}
+class C<Q> {
+  final List<Q> list = /*info:INFERRED_TYPE_LITERAL*/const [];
+  final Map<Q, Iterable<Q>> m =  /*info:INFERRED_TYPE_LITERAL*/const {};
+  const C();
+}
+main() {
+  const SetEquality<String>();
+}
+    ''');
+  }
+
+  void test_constantGenericTypeArg_explict() {
+    // Regression test for https://github.com/dart-lang/sdk/issues/26141
+    checkFile('''
+abstract class Equality<R> {}
+abstract class EqualityBase<R> implements Equality<R> {
+  final C<R> c = const C<R>();
+  const EqualityBase();
+}
+class DefaultEquality<S> extends EqualityBase<S> {
+  const DefaultEquality();
+}
+class SetEquality<T> implements Equality<T> {
+  final Equality<T> field = const DefaultEquality<T>();
+  const SetEquality([Equality<T> inner = const DefaultEquality<T>()]);
+}
+class C<Q> {
+  final List<Q> list = const <Q>[];
+  final Map<Q, Iterable<Q>> m =  const <Q, Iterable<Q>>{};
+  const C();
+}
+main() {
+  const SetEquality<String>();
+}
+    ''');
+  }
+
   void test_invalidOverrides_baseClassOverrideToChildInterface() {
     checkFile('''
 class A {}