Frontend: Do not suggest mode correction if adoption is not supported

Author: AnthonyLatsis

include/swift/AST/DiagnosticsFrontend.def

@@ -51,9 +51,9 @@ GROUPED_WARNING(feature_not_experimental, StrictLanguageFeatures, DefaultIgnore,
                 (StringRef, bool))
 
 GROUPED_WARNING(invalid_feature_mode, StrictLanguageFeatures, none,
-                "'%0' is not a recognized mode for feature '%1'; "
-                "did you mean '%2'?",
-                (StringRef, StringRef, StringRef))
+                "'%0' is not a recognized mode for feature '%1'"
+                "%select{|; did you mean '%2'?}3",
+                (StringRef, StringRef, StringRef, bool))
 
 GROUPED_WARNING(cannot_disable_feature_with_mode, StrictLanguageFeatures, none,
                 "'%0' argument '%1' cannot specify a mode",

lib/Frontend/CompilerInvocation.cpp

@@ -823,16 +823,19 @@ static bool ParseEnabledFeatureArgs(LangOptions &Opts, ArgList &Args,
 
     if (featureMode) {
       if (isEnableFeatureFlag) {
+        const auto isAdoptable = isFeatureAdoptable(*feature);
+
         // Diagnose an invalid mode.
         StringRef validModeName = "adoption";
         if (*featureMode != validModeName) {
           Diags.diagnose(SourceLoc(), diag::invalid_feature_mode, *featureMode,
                          featureName,
-                         /*didYouMean=*/validModeName);
+                         /*didYouMean=*/validModeName,
+                         /*showDidYouMean=*/isAdoptable);
           continue;
         }
 
-        if (!isFeatureAdoptable(*feature)) {
+        if (!isAdoptable) {
           Diags.diagnose(SourceLoc(),
                          diag::feature_does_not_support_adoption_mode,
                          featureName);

test/Frontend/strict_features_adoption_mode.swift

@@ -42,12 +42,12 @@
 // CHECK-SWIFT-5-NEXT: warning: '-disable-upcoming-feature' argument 'DynamicActorIsolation:invalid5' cannot specify a mode{{$}}
 // CHECK-SWIFT-5-NEXT: warning: feature 'DynamicActorIsolation' does not support adoption mode{{$}}
 // CHECK-SWIFT-5-NEXT: warning: feature 'DynamicActorIsolation' does not support adoption mode{{$}}
-// CHECK-SWIFT-5-NEXT: warning: 'invalid4' is not a recognized mode for feature 'DynamicActorIsolation'; did you mean 'adoption'?{{$}}
-// CHECK-SWIFT-5-NEXT: warning: 'invalid3' is not a recognized mode for feature 'DynamicActorIsolation'; did you mean 'adoption'?{{$}}
+// CHECK-SWIFT-5-NEXT: warning: 'invalid4' is not a recognized mode for feature 'DynamicActorIsolation'{{$}}
+// CHECK-SWIFT-5-NEXT: warning: 'invalid3' is not a recognized mode for feature 'DynamicActorIsolation'{{$}}
 // CHECK-SWIFT-5-NEXT: warning: feature 'DynamicActorIsolation' does not support adoption mode{{$}}
 // CHECK-SWIFT-5-NEXT: warning: feature 'DynamicActorIsolation' does not support adoption mode{{$}}
-// CHECK-SWIFT-5-NEXT: warning: 'invalid2' is not a recognized mode for feature 'DynamicActorIsolation'; did you mean 'adoption'?{{$}}
-// CHECK-SWIFT-5-NEXT: warning: 'invalid1' is not a recognized mode for feature 'DynamicActorIsolation'; did you mean 'adoption'?{{$}}
+// CHECK-SWIFT-5-NEXT: warning: 'invalid2' is not a recognized mode for feature 'DynamicActorIsolation'{{$}}
+// CHECK-SWIFT-5-NEXT: warning: 'invalid1' is not a recognized mode for feature 'DynamicActorIsolation'{{$}}
 // CHECK-SWIFT-5-NOT: warning:
 
 // CHECK-SWIFT-6-NOT: warning: