Fix and un-XFAIL regressed crashers from recent stdlib change

Author: slavapestov

lib/Sema/TypeCheckProtocol.cpp

@@ -4584,7 +4584,15 @@ void ConformanceChecker::resolveTypeWitnesses() {
     auto &typeWitnesses = solutions.front().TypeWitnesses;
     for (auto assocType : unresolvedAssocTypes) {
       assert(typeWitnesses.count(assocType) == 1 && "missing witness");
-      recordTypeWitness(assocType, typeWitnesses[assocType].first, nullptr, true);
+      auto replacement = typeWitnesses[assocType].first;
+      // FIXME: We can end up here with dependent types that were not folded
+      // away for some reason.
+      if (replacement.findIf([](Type t) -> bool {
+            return isa<DependentMemberType>(t.getPointer());
+          })) {
+        replacement = ErrorType::get(TC.Context);
+      }
+      recordTypeWitness(assocType, replacement, nullptr, true);
     }
 
     return;

test/decl/protocol/conforms/failure.swift

@@ -77,18 +77,18 @@ struct P5Conformer : P5 { // expected-error {{does not conform}}
 protocol P6Base {
   associatedtype Foo
   func foo()
-  func bar() -> Foo // expected-note{{protocol requires function 'bar()' with type '() -> P6Conformer.Bar?'; do you want to add a stub?}}
+  func bar() -> Foo
 }
 extension P6Base {
 }
 protocol P6 : P6Base {
   associatedtype Bar // expected-note {{protocol requires nested type 'Bar'}}
 }
 extension P6 {
-  func bar() -> Bar? { return nil } // expected-note{{candidate has non-matching type '<Self> () -> Self.Bar?' [with Foo = P6Conformer.Bar?]}}
+  func bar() -> Bar? { return nil }
 }
 
-struct P6Conformer : P6 { // expected-error 2 {{does not conform}}
+struct P6Conformer : P6 { // expected-error {{does not conform}}
   func foo() {}
 }
 

validation-test/IDE/crashers_fixed/subexpr-literal-in-sequence-expr.swift

@@ -1,6 +1,5 @@
 // RUN: %target-swift-ide-test -code-completion -code-completion-token=A -source-filename=%s | %FileCheck %s
 // RUN: %target-swift-ide-test -code-completion -code-completion-token=B -source-filename=%s | %FileCheck %s
-// XFAIL: *
 
 func test1() {
   1 + [0]#^A^#
@@ -9,4 +8,4 @@ func test2() {
   "" + [""]#^B^#
 }
 // Sanity check results.
-// CHECK: Decl[InfixOperatorFunction]/OtherModule[Swift]:  ==
+// CHECK: Decl[InstanceVar]/CurrNominal:      .startIndex[#Int#]; name=startIndex

validation-test/compiler_crashers_2_fixed/0019-rdar21511651.swift

@@ -1,5 +1,4 @@
 // RUN: not %target-swift-frontend %s -typecheck
-// XFAIL: *
 
 internal protocol _SequenceWrapper {
   typealias Base : Sequence

validation-test/compiler_crashers_2_fixed/0020-rdar21598514.swift

@@ -1,5 +1,4 @@
 // RUN: not %target-swift-frontend %s -typecheck
-// XFAIL: *
 
 protocol Resettable : AnyObject {
   func reset()

validation-test/compiler_crashers_fixed/23086-swift-typechecker-validatedecl.swift

@@ -6,7 +6,6 @@
 // See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
 
 // RUN: not %target-swift-frontend %s -typecheck
-// XFAIL: *
 struct Q<T,j{
 class a
 struct D:Collection

validation-test/compiler_crashers_fixed/24915-swift-typebase-getcanonicaltype.swift

@@ -6,5 +6,4 @@
 // See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
 
 // RUN: not %target-swift-frontend %s -typecheck
-// XFAIL: *
 struct B<T where B:A{{}struct c<T{struct d:Collection

validation-test/compiler_crashers_fixed/25011-swift-constraints-constraintsystem-opengeneric.swift

@@ -6,5 +6,4 @@
 // See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
 
 // RUN: not %target-swift-frontend %s -typecheck
-// XFAIL: *
 enum S<T where B:a{enum S:Collection

validation-test/compiler_crashers_fixed/26148-swift-typebase-getmembersubstitutions.swift

@@ -6,7 +6,6 @@
 // See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
 
 // RUN: not %target-swift-frontend %s -typecheck
-// XFAIL: *
 class B}struct B<T struct S<T{struct S<T let:{<T
 protocol c
 struct S<g{class A

validation-test/compiler_crashers_fixed/27034-swift-typechecker-validatedecl.swift

@@ -6,7 +6,6 @@
 // See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
 
 // RUN: not %target-swift-frontend %s -typecheck
-// XFAIL: *
 func b
 {
 {class A{class A:Collection

validation-test/compiler_crashers_fixed/27352-swift-astprinter-printtextimpl.swift

@@ -6,5 +6,4 @@
 // See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
 
 // RUN: not %target-swift-frontend %s -typecheck
-// XFAIL: *
 func b{struct Q<T where g:c{enum S{{}class a{class B{struct B{enum S<a{struct B{class a{struct Q{struct D:Collection

validation-test/compiler_crashers_fixed/27387-swift-structtype-get.swift

@@ -6,5 +6,4 @@
 // See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
 
 // RUN: not %target-swift-frontend %s -typecheck
-// XFAIL: *
 {struct Q<T{struct g:Collection}struct B<T:T.E

validation-test/compiler_crashers_fixed/28041-swift-typechecker-lookupunqualified.swift

@@ -6,7 +6,6 @@
 // See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
 
 // Test is no longer valid as there is no longer `map` as a free function in Swift 3
-// XFAIL: *
 // DUPLICATE-OF: 26813-generic-enum-tuple-optional-payload.swift
-// RUN: not --crash %target-swift-frontend %s -typecheck
+// RUN: not %target-swift-frontend %s -typecheck
 let a{{map($0

validation-test/compiler_crashers_fixed/28577-isa-x-val-cast-ty-argument-of-incompatible-type.swift

@@ -6,5 +6,4 @@
 // See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
 
 // RUN: not %target-swift-frontend %s -emit-ir
-// XFAIL: *
 class a<U:a>:RangeReplaceableCollection

validation-test/compiler_crashers_fixed/28666-conformingreplacementtype-is-substitutabletype-conformingreplacementtype-is-depe.swift

@@ -6,5 +6,4 @@
 // See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
 
 // RUN: not %target-swift-frontend %s -emit-ir
-// XFAIL: *
 struct A:RangeReplaceableCollection{var f=max

validation-test/compiler_crashers_fixed/28670-reftype-hastypeparameter-cannot-have-a-dependent-type-here.swift

@@ -6,5 +6,4 @@
 // See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
 
 // RUN: not %target-swift-frontend %s -emit-ir
-// XFAIL: *
 struct A:RangeReplaceableCollection{let c{{a f{}}var f=max