[Sema] NFC: reword "only concrete types can conform to protocols" diagnostic

Author: xedin

include/swift/AST/DiagnosticsSema.def

@@ -1508,8 +1508,8 @@ ERROR(use_of_equal_instead_of_equality,none,
 
 
 ERROR(protocol_does_not_conform_objc,none,
-      "using %0 as a concrete type conforming to protocol %1 is not supported",
-      (Type, Type))
+      "protocol type %0 cannot conform to %1 because only concrete "
+      "types can conform to protocols", (Type, Type))
 ERROR(protocol_does_not_conform_static,none,
       "%0 cannot be used as a type conforming to protocol %1 because %1 "
       "has static requirements",

lib/Sema/CSSimplify.cpp

@@ -2779,7 +2779,7 @@ ConstraintSystem::SolutionKind ConstraintSystem::simplifyConformsToConstraint(
       auto typeRequirement = path.back();
       std::pair<Expr *, unsigned> reqLoc = {anchor, typeRequirement.getValue()};
       MissingConformances[reqLoc] = {type.getPointer(), protocol};
-      // Let's strip all of the uncessary information from locator,
+      // Let's strip all of the unnecessary information from locator,
       // diagnostics only care about anchor - to lookup type,
       // and what was the requirement# which is not satisfied.
       ConstraintLocatorBuilder requirement(getConstraintLocator(anchor));

lib/Sema/ConstraintSystem.h

@@ -1009,7 +1009,7 @@ class ConstraintSystem {
   /// Argument labels fixed by the constraint solver.
   SmallVector<std::vector<Identifier>, 4> FixedArgLabels;
 
-  /// Conformances which solver "fixed" to exist to help with
+  /// Conformances which solver "fixed" to help with
   /// diagnosing problems related to generic requirements.
   llvm::SmallDenseMap<std::pair<Expr *, unsigned>,
                       std::pair<TypeBase *, ProtocolDecl *>>

test/Constraints/generics.swift

@@ -188,7 +188,7 @@ func r22459135() {
 
 // <rdar://problem/19710848> QoI: Friendlier error message for "[] as Set"
 // <rdar://problem/22326930> QoI: "argument for generic parameter 'Element' could not be inferred" lacks context
-_ = [] as Set  // expected-error {{using 'Any' as a concrete type conforming to protocol 'Hashable' is not supported}}
+_ = [] as Set  // expected-error {{protocol type 'Any' cannot conform to 'Hashable' because only concrete types can conform to protocols}}
 
 
 //<rdar://problem/22509125> QoI: Error when unable to infer generic archetype lacks greatness

test/Generics/existential_restrictions.swift

@@ -17,7 +17,7 @@ func fAOE(_ t: AnyObject) { }
 func fT<T>(_ t: T) { }
 
 func testPassExistential(_ p: P, op: OP, opp: OP & P, cp: CP, sp: SP, any: Any, ao: AnyObject) {
-  fP(p) // expected-error{{using 'P' as a concrete type conforming to protocol 'P' is not supported}}
+  fP(p) // expected-error{{protocol type 'P' cannot conform to 'P' because only concrete types can conform to protocols}}
   fAO(p) // expected-error{{cannot invoke 'fAO' with an argument list of type '(P)'}} // expected-note{{expected an argument list of type '(T)'}}
   fAOE(p) // expected-error{{argument type 'P' does not conform to expected type 'AnyObject'}}
   fT(p)
@@ -31,8 +31,8 @@ func testPassExistential(_ p: P, op: OP, opp: OP & P, cp: CP, sp: SP, any: Any,
   fAOE(cp)
   fT(cp)
 
-  fP(opp) // expected-error{{using 'OP & P' as a concrete type conforming to protocol 'P' is not supported}}
-  fOP(opp) // expected-error{{using 'OP & P' as a concrete type conforming to protocol 'OP' is not supported}}
+  fP(opp) // expected-error{{protocol type 'OP & P' cannot conform to 'P' because only concrete types can conform to protocols}}
+  fOP(opp) // expected-error{{protocol type 'OP & P' cannot conform to 'OP' because only concrete types can conform to protocols}}
   fAO(opp) // expected-error{{cannot invoke 'fAO' with an argument list of type '(OP & P)'}} // expected-note{{expected an argument list of type '(T)'}}
   fAOE(opp)
   fT(opp)
@@ -58,9 +58,9 @@ class GAO<T : AnyObject> {} // expected-note 2{{requirement specified as 'T' : '
 func blackHole(_ t: Any) {}
 
 func testBindExistential() {
-  blackHole(GP<P>()) // expected-error{{using 'P' as a concrete type conforming to protocol 'P' is not supported}}
+  blackHole(GP<P>()) // expected-error{{protocol type 'P' cannot conform to 'P' because only concrete types can conform to protocols}}
   blackHole(GOP<OP>())
-  blackHole(GCP<CP>()) // expected-error{{using 'CP' as a concrete type conforming to protocol 'CP' is not supported}}
+  blackHole(GCP<CP>()) // expected-error{{protocol type 'CP' cannot conform to 'CP' because only concrete types can conform to protocols}}
   blackHole(GAO<P>()) // expected-error{{'GAO' requires that 'P' be a class type}}
   blackHole(GAO<OP>())
   blackHole(GAO<CP>()) // expected-error{{'GAO' requires that 'CP' be a class type}}
@@ -85,5 +85,5 @@ func foo() {
   // generic no overloads error path. The error should actually talk
   // about the return type, and this can happen in other contexts as well;
   // <rdar://problem/21900971> tracks improving QoI here.
-  allMine.takeAll() // expected-error{{using 'Mine' as a concrete type conforming to protocol 'Mine' is not supported}}
+  allMine.takeAll() // expected-error{{protocol type 'Mine' cannot conform to 'Mine' because only concrete types can conform to protocols}}
 }

test/stmt/foreach.swift

@@ -176,7 +176,7 @@ func testOptionalSequence() {
 
 // Crash with (invalid) for each over an existential
 func testExistentialSequence(s: Sequence) { // expected-error {{protocol 'Sequence' can only be used as a generic constraint because it has Self or associated type requirements}}
-  for x in s { // expected-error {{using 'Sequence' as a concrete type conforming to protocol 'Sequence' is not supported}}
+  for x in s { // expected-error {{protocol type 'Sequence' cannot conform to 'Sequence' because only concrete types can conform to protocols}}
     _ = x
   }
 }

test/type/subclass_composition.swift

@@ -407,7 +407,7 @@ func conformsTo<T1 : P2, T2 : Base<Int> & P2>(
   // expected-note@-2 {{expected an argument list of type '(T)'}}
 
   conformsToP1(p1)
-  // expected-error@-1 {{using 'P1' as a concrete type conforming to protocol 'P1' is not supported}}
+  // expected-error@-1 {{protocol type 'P1' cannot conform to 'P1' because only concrete types can conform to protocols}}
 
   // FIXME: Following diagnostics are not great because when
   // `conformsTo*` methods are re-typechecked, they loose information

validation-test/compiler_crashers_fixed/00017-llvm-foldingset-llvm-attributesetnode-nodeequals.swift

@@ -19,4 +19,4 @@ extension Bool : BooleanProtocol {
 }
 func f<T : BooleanProtocol>(_ b: T) {
 }
-f(true as BooleanProtocol) // expected-error {{using 'BooleanProtocol' as a concrete type conforming to protocol 'BooleanProtocol' is not supported}}
+f(true as BooleanProtocol) // expected-error {{protocol type 'BooleanProtocol' cannot conform to 'BooleanProtocol' because only concrete types can conform to protocols}}