[gsb] check if the subject type has an assoc type decl

Author: Suyash Srijan

lib/AST/GenericSignatureBuilder.cpp

@@ -5775,11 +5775,12 @@ GenericSignatureBuilder::finalize(SourceLoc loc,
         return subjectTypeName;
       };
 
-      if (allowConcreteGenericParams || subjectType->is<DependentMemberType>()) {
+      auto DMT = subjectType->getAs<DependentMemberType>();
+      
+      if (allowConcreteGenericParams || (DMT && !DMT->getAssocType())) {
         auto subjectTypeName = subjectType.getString();
         auto subjectTypeNameWithoutSelf = getNameWithoutSelf(subjectTypeName);
-        Diags.diagnose(loc,
-                       diag::requires_conformance_nonprotocol_fixit,
+        Diags.diagnose(loc, diag::requires_conformance_nonprotocol_fixit,
                        subjectTypeNameWithoutSelf, constraintType.getString())
              .fixItReplace(loc, " == ");
       }

test/Constraints/generics.swift

@@ -664,3 +664,7 @@ extension SR_7984_X where T.Assoc.Foo: String {} // expected-error {{type 'T.Ass
 
 struct SR_7984_S<T: Sequence> where T.Element: String {} // expected-error {{type 'T.Element' constrained to non-protocol, non-class type 'String'}} expected-note {{use 'T.Element == String' to require 'T.Element' to be 'String'}} {{46-47= ==}}
 func SR_7984_F<T: Sequence>(foo: T) where T.Element: String {} // expected-error {{type 'T.Element' constrained to non-protocol, non-class type 'String'}} expected-note {{use 'T.Element == String' to require 'T.Element' to be 'String'}} {{52-53= ==}}
+
+protocol SR_7984_P {
+  func S<T : Sequence>(bar: T) where T.Element: String // expected-error {{type 'T.Element' constrained to non-protocol, non-class type 'String'}} expected-note {{use 'T.Element == String' to require 'T.Element' to be 'String'}} {{47-48= ==}}
+}

test/NameBinding/scope_map_lookup.swift

@@ -26,7 +26,7 @@ protocol P1 {
 protocol AProtocol {
   associatedtype e : e
   // expected-error@-1 {{inheritance from non-protocol, non-class type 'Self.e'}}
-  // expected-error@-2 {{type 'Self.e' constrained to non-protocol, non-class type 'Self.e'}} expected-note@-2 {{use 'e == Self.e' to require 'e' to be 'Self.e'}} {{22-23===}}
+  // expected-error@-2 {{type 'Self.e' constrained to non-protocol, non-class type 'Self.e'}}
 }
 
 // Extensions.

test/Sema/circular_decl_checking.swift

@@ -46,7 +46,7 @@ var TopLevelVar: TopLevelVar? { return nil } // expected-error {{use of undeclar
 // FIXME: The first error is redundant and isn't correct in what it states.
 protocol AProtocol {
   associatedtype e : e
-  // expected-error@-1 {{type 'Self.e' constrained to non-protocol, non-class type 'Self.e'}} expected-note@-1 {{use 'e == Self.e' to require 'e' to be 'Self.e'}} {{22-23===}}
+  // expected-error@-1 {{type 'Self.e' constrained to non-protocol, non-class type 'Self.e'}}
   // expected-error@-2 {{inheritance from non-protocol, non-class type 'Self.e'}}
 }
 

test/decl/protocol/req/unsatisfiable.swift

@@ -43,24 +43,24 @@ protocol Base {
 // same type.
 protocol Sub1: Base {
   associatedtype SubAssoc: Assoc
-  // expected-error@-1 {{type 'Self.SubAssoc' constrained to non-protocol, non-class type 'Self.Assoc'}} expected-note@-1 {{use 'SubAssoc == Self.Assoc' to require 'SubAssoc' to be 'Self.Assoc'}} {{28-33===}}
+  // expected-error@-1 {{type 'Self.SubAssoc' constrained to non-protocol, non-class type 'Self.Assoc'}}
   // expected-error@-2 {{inheritance from non-protocol, non-class type 'Self.Assoc'}}
 }
 
 // FIXME: This error is incorrect in what it states.
 protocol Sub2: Base {
-  associatedtype SubAssoc where SubAssoc: Assoc // expected-error {{type 'Self.SubAssoc' constrained to non-protocol, non-class type 'Self.Assoc'}} expected-note {{use 'SubAssoc == Self.Assoc' to require 'SubAssoc' to be 'Self.Assoc'}} {{41-42= ==}}
+  associatedtype SubAssoc where SubAssoc: Assoc // expected-error {{type 'Self.SubAssoc' constrained to non-protocol, non-class type 'Self.Assoc'}}
 }
 
 struct S {}
 
 // FIX-ME: One of these errors is redundant.
 protocol P4 {
   associatedtype X : S
-  // expected-error@-1 {{type 'Self.X' constrained to non-protocol, non-class type 'S'}} expected-note@-1 {{use 'X == S' to require 'X' to be 'S'}} {{22-23===}}
+  // expected-error@-1 {{type 'Self.X' constrained to non-protocol, non-class type 'S'}}
   // expected-error@-2 {{inheritance from non-protocol, non-class type 'S'}}
 }
 
 protocol P5 {
-  associatedtype Y where Y : S // expected-error {{type 'Self.Y' constrained to non-protocol, non-class type 'S'}} expected-note {{use 'Y == S' to require 'Y' to be 'S'}} {{28-29===}}
+  associatedtype Y where Y : S // expected-error {{type 'Self.Y' constrained to non-protocol, non-class type 'S'}}
 }