Merge pull request swiftlang#28465 from zoecarver/feature/variadic-args-key-path-subscript

Fix variadic args in key path subscript

Author: slavapestov

lib/Sema/CSApply.cpp

@@ -4571,7 +4571,7 @@ namespace {
       for (auto &param : fnType->getParams()) {
         newLabels.push_back(param.getLabel());
 
-        auto indexType = simplifyType(param.getPlainType());
+        auto indexType = simplifyType(param.getParameterType());
         // Index type conformance to Hashable protocol has been
         // verified by the solver, we just need to get it again
         // with all of the generic parameters resolved.

lib/Sema/ConstraintSystem.cpp

@@ -2281,7 +2281,7 @@ void ConstraintSystem::resolveOverload(ConstraintLocator *locator,
         // Hashable, because it would be used as a component inside key path.
         for (auto index : indices(subscriptTy->getParams())) {
           const auto &param = subscriptTy->getParams()[index];
-          verifyThatArgumentIsHashable(index, param.getPlainType(), locator);
+          verifyThatArgumentIsHashable(index, param.getParameterType(), locator);
         }
       }
     }

test/SILGen/keypaths.swift

@@ -452,6 +452,53 @@ func check_default_subscripts() {
   _ = \SubscriptDefaults5.[x: "", y: ""]
 }
 
+struct SubscriptVariadic1 {
+  subscript(x: Int...) -> Int { x[0] }
+}
+
+struct SubscriptVariadic2 {
+  subscript<T : ExpressibleByStringLiteral>(x: T...) -> T { x[0] }
+}
+
+struct SubscriptVariadic3<T : ExpressibleByStringLiteral> {
+  subscript(x: T...) -> T { x[0] }
+}
+
+// CHECK-LABEL: sil hidden [ossa] @{{.*}}test_variadics
+func test_variadics() {
+  // CHECK: [[ARR_COUNT:%[0-9]+]] = integer_literal $Builtin.Word, 3
+  // CHECK: [[FN_REF:%[0-9]+]] = function_ref @$ss27_allocateUninitializedArrayySayxG_BptBwlF
+  // CHECK: [[MAKE_ARR:%[0-9]+]] = apply [[FN_REF]]<Int>([[ARR_COUNT]])
+  // CHECK: ([[ARR:%[0-9]+]], %{{[0-9]+}}) = destructure_tuple [[MAKE_ARR]] : $(Array<Int>, Builtin.RawPointer)
+  // CHECK: keypath $KeyPath<SubscriptVariadic1, Int>, (root $SubscriptVariadic1; gettable_property $Int,  id @$s8keypaths18SubscriptVariadic1VyS2id_tcig : $@convention(method) (@guaranteed Array<Int>, SubscriptVariadic1) -> Int, getter @$s8keypaths18SubscriptVariadic1VyS2id_tcipACTK : $@convention(thin) (@in_guaranteed SubscriptVariadic1, UnsafeRawPointer) -> @out Int, indices [%$0 : $Array<Int> : $Array<Int>], indices_equals @$sSaySiGTH : $@convention(thin) (UnsafeRawPointer, UnsafeRawPointer) -> Bool, indices_hash @$sSaySiGTh : $@convention(thin) (UnsafeRawPointer) -> Int) ([[ARR]])
+  _ = \SubscriptVariadic1.[1, 2, 3]
+  // CHECK: [[ARR_COUNT:%[0-9]+]] = integer_literal $Builtin.Word, 1
+  // CHECK: [[FN_REF:%[0-9]+]] = function_ref @$ss27_allocateUninitializedArrayySayxG_BptBwlF
+  // CHECK: [[MAKE_ARR:%[0-9]+]] = apply [[FN_REF]]<Int>([[ARR_COUNT]])
+  // CHECK: ([[ARR:%[0-9]+]], %{{[0-9]+}}) = destructure_tuple [[MAKE_ARR]] : $(Array<Int>, Builtin.RawPointer)
+  // CHECK: keypath $KeyPath<SubscriptVariadic1, Int>, (root $SubscriptVariadic1; gettable_property $Int,  id @$s8keypaths18SubscriptVariadic1VyS2id_tcig : $@convention(method) (@guaranteed Array<Int>, SubscriptVariadic1) -> Int, getter @$s8keypaths18SubscriptVariadic1VyS2id_tcipACTK : $@convention(thin) (@in_guaranteed SubscriptVariadic1, UnsafeRawPointer) -> @out Int, indices [%$0 : $Array<Int> : $Array<Int>], indices_equals @$sSaySiGTH : $@convention(thin) (UnsafeRawPointer, UnsafeRawPointer) -> Bool, indices_hash @$sSaySiGTh : $@convention(thin) (UnsafeRawPointer) -> Int) ([[ARR]])
+  _ = \SubscriptVariadic1.[1]
+  // CHECK: [[ARR_COUNT:%[0-9]+]] = integer_literal $Builtin.Word, 0
+  // CHECK: [[FN_REF:%[0-9]+]] = function_ref @$ss27_allocateUninitializedArrayySayxG_BptBwlF
+  // CHECK: [[MAKE_ARR:%[0-9]+]] = apply [[FN_REF]]<Int>([[ARR_COUNT]])
+  // CHECK: ([[ARR:%[0-9]+]], %{{[0-9]+}}) = destructure_tuple [[MAKE_ARR]] : $(Array<Int>, Builtin.RawPointer)
+  // CHECK: keypath $KeyPath<SubscriptVariadic1, Int>, (root $SubscriptVariadic1; gettable_property $Int,  id @$s8keypaths18SubscriptVariadic1VyS2id_tcig : $@convention(method) (@guaranteed Array<Int>, SubscriptVariadic1) -> Int, getter @$s8keypaths18SubscriptVariadic1VyS2id_tcipACTK : $@convention(thin) (@in_guaranteed SubscriptVariadic1, UnsafeRawPointer) -> @out Int, indices [%$0 : $Array<Int> : $Array<Int>], indices_equals @$sSaySiGTH : $@convention(thin) (UnsafeRawPointer, UnsafeRawPointer) -> Bool, indices_hash @$sSaySiGTh : $@convention(thin) (UnsafeRawPointer) -> Int) ([[ARR]])
+  _ = \SubscriptVariadic1.[]
+  
+  _ = \SubscriptVariadic2.["", "1"]
+  _ = \SubscriptVariadic2.[""]
+  // CHECK: [[ARR_COUNT:%[0-9]+]] = integer_literal $Builtin.Word, 2
+  // CHECK: [[FN_REF:%[0-9]+]] = function_ref @$ss27_allocateUninitializedArrayySayxG_BptBwlF
+  // CHECK: [[MAKE_ARR:%[0-9]+]] = apply [[FN_REF]]<String>([[ARR_COUNT]])
+  // CHECK: ([[ARR:%[0-9]+]], %{{[0-9]+}}) = destructure_tuple [[MAKE_ARR]] : $(Array<String>, Builtin.RawPointer)
+  // CHECK: keypath $KeyPath<SubscriptVariadic2, String>, (root $SubscriptVariadic2; gettable_property $String,  id @$s8keypaths18SubscriptVariadic2Vyxxd_tcs26ExpressibleByStringLiteralRzluig : $@convention(method) <τ_0_0 where τ_0_0 : ExpressibleByStringLiteral> (@guaranteed Array<τ_0_0>, SubscriptVariadic2) -> @out τ_0_0, getter @$s8keypaths18SubscriptVariadic2Vyxxd_tcs26ExpressibleByStringLiteralRzluipACSSTK : $@convention(thin) (@in_guaranteed SubscriptVariadic2, UnsafeRawPointer) -> @out String, indices [%$0 : $Array<String> : $Array<String>], indices_equals @$sSaySSGTH : $@convention(thin) (UnsafeRawPointer, UnsafeRawPointer) -> Bool, indices_hash @$sSaySSGTh : $@convention(thin) (UnsafeRawPointer) -> Int) ([[ARR]])
+  _ = \SubscriptVariadic2.["", #function]
+  
+  _ = \SubscriptVariadic3<String>.[""]
+  _ = \SubscriptVariadic3<String>.["", "1"]
+  _ = \SubscriptVariadic3<String>.[]
+}
+
 // CHECK-LABEL: sil hidden [ossa] @{{.*}}subclass_generics
 func subclass_generics<T: C<Int>, U: C<V>, V/*: PoC*/>(_: T, _: U, _: V) {
   _ = \T.x