| // Copyright (c) 2018, 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. |
| |
| /// @assertion Instantiate to bound then computes an actual type argument list |
| /// for [G] as follows: |
| /// |
| /// Let [Ui],[1] be [Si], for all [i] in [1 .. k]. (This is the "current |
| /// value" of the bound for type variable [i], at step [1]; in general we will |
| /// consider the current step, [m], and use data for that step, e.g., the |
| /// bound [Ui],[m], to compute the data for step [m + 1]). |
| /// |
| /// Let [-->m] be a relation among the type variables [X1 .. Xk] such that |
| /// [Xp -->m Xq] iff [Xq] occurs in [Up],[m] (so each type variable is related |
| /// to, that is, depends on, every type variable in its bound, possibly |
| /// including itself). Let [==>m] be the transitive closure of [-->m]. For |
| /// each [m], let [Ui],[m+1], for [i] in [1 .. k], be determined by the |
| /// following iterative process: |
| /// |
| /// 1. If there exists a [j] in [1 .. k] such that [Xj ==>m X0j] (that is, if |
| /// the dependency graph has a cycle) let [M1 .. Mp] be the strongly connected |
| /// components (SCCs) with respect to [-->m] (that is, the maximal subsets of |
| /// [X1 .. Xk] where every pair of variables in each subset are related in |
| /// both directions by [==>m]; note that the SCCs are pairwise disjoint; also, |
| /// they are uniquely defined up to reordering, and the order does not |
| /// matter). Let [M] be the union of [M1 .. Mp] (that is, all variables that |
| /// participate in a dependency cycle). Let [i] be in [1 .. k]. If [Xi] does |
| /// not belong to [M] then [Ui,m+1 = Ui,m]. Otherwise there exists a [q] such |
| /// that [Xi] belongs to [Mq]; [Ui,m+1] is then obtained from [Ui,m] by |
| /// replacing every covariant occurrence of a variable in [Mq] by [dynamic], |
| /// and replacing every contravariant occurrence of a variable in [Mq] by |
| /// [Null]. |
| /// |
| /// 2. Otherwise, (if no dependency cycle exists) let [j] be the lowest number |
| /// such that [Xj] occurs in [Up,m] for some [p] and [Xj -/->m Xq] for all [q] |
| /// in [1..k] (that is, [Uj,m] is closed, that is, the current bound of [Xj] |
| /// does not contain any type variables; but [Xj] is being depended on by the |
| /// bound of some other type variable). Then, for all [i] in [1 .. k], |
| /// [Ui,m+1] is obtained from [Ui,m] by replacing every covariant occurrence |
| /// of [Xj] by [Uj,m], and replacing every contravariant occurrence of [Xj] by |
| /// [Null]. |
| /// |
| /// 3. Otherwise, (when no dependencies exist) terminate with the result |
| /// [<U1,m ..., Uk,m>]. |
| /// |
| /// @description Checks that instantiate-to-bounds works correctly for typedef |
| /// with two related parameters: |
| /// typedef G<X extends Y, Y extends A<Y>> = void Function(Y)] |
| /// |
| /// @Issue 41963, 41964 |
| /// |
| /// @author iarkh@unipro.ru |
| |
| import "../../../../Utils/expect.dart"; |
| |
| class A<X> {} |
| typedef G<X extends Y, Y extends A<Y>> = void Function(Y); |
| |
| test(G source) { |
| var fsource = toF(source); |
| |
| F<G<A<dynamic>, Never>> target1 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<A<Never>, Never>> target2 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<A<Null>, Never>> target3 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<dynamic, Never>> target4 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<Never, Never>> target5 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<Null, Never>> target6 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<A<dynamic>, dynamic>> target7 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<A<Never>, dynamic>> target8 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<A<Null>, dynamic>> target9 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<dynamic, dynamic>> target10 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<Never, dynamic>> target11 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<Null, dynamic>> target12 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<A<dynamic>, Null>> target13 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<A<Never>, Null>> target14 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<A<Null>, Null>> target15 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<dynamic, Null>> target16 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<Never, Null>> target17 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<Null, Null>> target18 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<A<Never>, A<dynamic>>> target19 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<A<dynamic>, A<dynamic>>> target20 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<A<dynamic>, A<Never>>> target21 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<A<Never>, A<Never>>> target22 = fsource; |
| |
| F<G<A<dynamic>, A<Null>>> target23 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<A<Null>, A<dynamic>>> target24 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| F<G<A<Null>, A<Null>>> target25 = fsource; |
| // ^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| } |
| |
| main() { |
| G? source; |
| G == int; |
| } |
