ABI/API checker: avoid printing fully qualified names in generic signature

The heuristics to decide whether fully qualified type names should be printed may
work differently when generating the baseline and when importing from just built
frameworks. This patch makes it consistent so that such false positives won't happen.

rdar://54276347

Author: nkcsgexi

test/api-digester/Outputs/Cake-abi.txt

@@ -1,7 +1,7 @@
 
 /* Generic Signature Changes */
 cake: Func P1.P1Constraint() has generic signature change from <τ_0_0 where τ_0_0 : P1, τ_0_0 : P2> to <τ_0_0 where τ_0_0 : P1>
-cake: Protocol P3 has generic signature change from <τ_0_0 : cake.P1, τ_0_0 : cake.P2> to <τ_0_0 : cake.P1, τ_0_0 : cake.P4>
+cake: Protocol P3 has generic signature change from <τ_0_0 : P1, τ_0_0 : P2> to <τ_0_0 : P1, τ_0_0 : P4>
 
 /* RawRepresentable Changes */
 

test/api-digester/Outputs/Cake.txt

@@ -1,7 +1,7 @@
 
 /* Generic Signature Changes */
 cake: Func P1.P1Constraint() has generic signature change from <Self where Self : P1, Self : P2> to <Self where Self : P1>
-cake: Protocol P3 has generic signature change from <Self : cake.P1, Self : cake.P2> to <Self : cake.P1, Self : cake.P4>
+cake: Protocol P3 has generic signature change from <Self : P1, Self : P2> to <Self : P1, Self : P4>
 
 /* RawRepresentable Changes */
 

test/api-digester/Outputs/cake-abi.json

@@ -59,7 +59,7 @@
       "declKind": "Protocol",
       "usr": "s:4cake2P3P",
       "moduleName": "cake",
-      "genericSig": "<τ_0_0 : cake.P1, τ_0_0 : cake.P2>",
+      "genericSig": "<τ_0_0 : P1, τ_0_0 : P2>",
       "conformances": [
         {
           "kind": "Conformance",
@@ -1235,7 +1235,7 @@
       "declKind": "Protocol",
       "usr": "s:4cake4PSubP",
       "moduleName": "cake",
-      "genericSig": "<τ_0_0 : cake.PSuper>",
+      "genericSig": "<τ_0_0 : PSuper>",
       "conformances": [
         {
           "kind": "Conformance",

test/api-digester/Outputs/cake.json

@@ -59,7 +59,7 @@
       "declKind": "Protocol",
       "usr": "s:4cake2P3P",
       "moduleName": "cake",
-      "genericSig": "<Self : cake.P1, Self : cake.P2>",
+      "genericSig": "<Self : P1, Self : P2>",
       "conformances": [
         {
           "kind": "Conformance",
@@ -1137,7 +1137,7 @@
       "declKind": "Protocol",
       "usr": "s:4cake4PSubP",
       "moduleName": "cake",
-      "genericSig": "<Self : cake.PSuper>",
+      "genericSig": "<Self : PSuper>",
       "conformances": [
         {
           "kind": "Conformance",

tools/swift-api-digester/ModuleAnalyzerNodes.cpp

@@ -1090,16 +1090,20 @@ StringRef printGenericSignature(SDKContext &Ctx, ArrayRef<Requirement> AllReqs)
     return StringRef();
   OS << "<";
   bool First = true;
+  PrintOptions Opts = PrintOptions::printInterface();
+  // We always print unqualifed type names to avoid false positives introduced
+  // by the heuristics working differently.
+  Opts.FullyQualifiedTypesIfAmbiguous = false;
   for (auto Req: AllReqs) {
     if (!First) {
       OS << ", ";
     } else {
       First = false;
     }
     if (Ctx.checkingABI())
-      getCanonicalRequirement(Req).print(OS, PrintOptions::printInterface());
+      getCanonicalRequirement(Req).print(OS, Opts);
     else
-      Req.print(OS, PrintOptions::printInterface());
+      Req.print(OS, Opts);
   }
   OS << ">";
   return Ctx.buffer(OS.str());