Merge pull request #41842 from slavapestov/gsb-relax-verify-check

GSB: Relax -requirement-machine-protocol-signatures=verify check a little

Author: slavapestov

lib/AST/GenericSignatureBuilder.cpp

@@ -8662,23 +8662,24 @@ RequirementSignatureRequest::evaluate(Evaluator &evaluator,
 
   auto compare = [&](ArrayRef<Requirement> rqmResult,
                      ArrayRef<Requirement> gsbResult) {
-    if (proto->getParentModule()->isStdlibModule() &&
-        (proto->getName().is("Collection") ||
-         proto->getName().is("StringProtocol"))) {
-      if (rqmResult.size() > gsbResult.size())
-        return false;
-    } else {
-      if (rqmResult.size() != gsbResult.size())
+    if (rqmResult.size() > gsbResult.size())
+      return false;
+    
+    if (!std::equal(rqmResult.begin(),
+                    rqmResult.end(),
+                    gsbResult.begin(),
+                    [](const Requirement &lhs,
+                       const Requirement &rhs) {
+                      return lhs.getCanonical() == rhs.getCanonical();
+                    }))
+      return false;
+
+    for (auto req : gsbResult.slice(rqmResult.size())) {
+      if (req.getKind() != RequirementKind::SameType)
         return false;
     }
 
-    return std::equal(rqmResult.begin(),
-                      rqmResult.end(),
-                      gsbResult.begin(),
-                      [](const Requirement &lhs,
-                         const Requirement &rhs) {
-                        return lhs.getCanonical() == rhs.getCanonical();
-                      });
+    return true;
   };
 
   switch (ctx.LangOpts.RequirementMachineProtocolSignatures) {

test/Generics/sr8968.swift

@@ -0,0 +1,56 @@
+// RUN: %target-typecheck-verify-swift -requirement-machine-protocol-signatures=on
+// RUN: %target-swift-frontend -typecheck %s -debug-generic-signatures -requirement-machine-protocol-signatures=on 2>&1 | %FileCheck %s
+
+public class OFMAttachment : NativeInserting {
+// expected-warning@-1 {{non-final class 'OFMAttachment' cannot safely conform to protocol 'NativeInserting', which requires that 'Self.SnapshotType.NativeType' is exactly equal to 'Self'; this is an error in Swift 6}}
+    public typealias SnapshotType = Message.Attachment
+}
+
+// CHECK-LABEL: .Snapshotting@
+// CHECK-NEXT: Requirement signature: <Self where Self == Self.[Snapshotting]ChangeType.[SnapshotChange]SnapshotType, Self.[Snapshotting]ChangeType : SnapshotChange, Self.[Snapshotting]NativeType : NativeInserting, Self.[Snapshotting]RecordType : SnapshotRecord, Self.[Snapshotting]ChangeType.[SnapshotChange]SnapshotType == Self.[Snapshotting]NativeType.[NativeInserting]SnapshotType, Self.[Snapshotting]NativeType.[NativeInserting]SnapshotType == Self.[Snapshotting]RecordType.[SnapshotRecord]SnapshotType>
+public protocol Snapshotting {
+    associatedtype NativeType: NativeInserting where NativeType.SnapshotType == Self
+    associatedtype RecordType: SnapshotRecord where RecordType.SnapshotType == Self
+    associatedtype ChangeType: SnapshotChange where ChangeType.SnapshotType == Self
+
+    static var baseMessageName: String { get }
+}
+
+// CHECK-LABEL: .NativeInserting@
+// CHECK-NEXT: Requirement signature: <Self where Self == Self.[NativeInserting]SnapshotType.[Snapshotting]NativeType, Self.[NativeInserting]SnapshotType : Snapshotting>
+public protocol NativeInserting {
+    associatedtype SnapshotType : Snapshotting where SnapshotType.NativeType == Self
+}
+
+// CHECK-LABEL: .SnapshotRecord@
+// CHECK-NEXT: Requirement signature: <Self where Self == Self.[SnapshotRecord]SnapshotType.[Snapshotting]RecordType, Self.[SnapshotRecord]SnapshotType : Snapshotting>
+public protocol SnapshotRecord {
+    associatedtype SnapshotType : Snapshotting where SnapshotType.RecordType == Self
+
+}
+
+// CHECK-LABEL: .SnapshotChange@
+// CHECK-NEXT: Requirement signature: <Self where Self == Self.[SnapshotChange]SnapshotType.[Snapshotting]ChangeType, Self.[SnapshotChange]SnapshotType : Snapshotting>
+public protocol SnapshotChange {
+    associatedtype SnapshotType : Snapshotting where SnapshotType.ChangeType == Self
+}
+
+public struct Message {
+    public enum Attachment : Snapshotting {
+
+        public static var baseMessageName: String = "attachment"
+
+        public typealias NativeType = OFMAttachment
+        public typealias RecordType = Record
+        public typealias ChangeType = Change
+        public struct Record : SnapshotRecord {
+            public typealias SnapshotType = Message.Attachment
+        }
+
+        public struct Change : SnapshotChange {
+            public typealias SnapshotType = Message.Attachment
+        }
+
+    }
+}
+