Swift: Mangle ArchetypeTypes with different constraints in different extensions.

Author: sashabu

swift/extractor/mangler/SwiftMangler.cpp

@@ -307,7 +307,15 @@ SwiftMangledName SwiftMangler::visitTypeAliasType(const swift::TypeAliasType* ty
 }
 
 SwiftMangledName SwiftMangler::visitArchetypeType(const swift::ArchetypeType* type) {
-  return initMangled(type) << fetch(type->getInterfaceType());
+  auto ret = initMangled(type) << fetch(type->getInterfaceType());
+  for (const auto* protocol : type->getConformsTo()) {
+    // Including the protocols in the mangled name allows us to distinguish the "same" type in
+    // different extensions, where it might have different constraints. Mangling the context (i.e.
+    // which ExtensionDecl or ValueDecl it's mentioned in) might be more robust, but there doesn't
+    // seem to be a clean way to get it.
+    ret << ':' << fetch(protocol);
+  }
+  return ret;
 }
 
 SwiftMangledName SwiftMangler::visitOpaqueTypeArchetypeType(

swift/ql/test/extractor-tests/generated/type/PrimaryArchetypeType/PrimaryArchetypeType.expected

@@ -1,3 +1,5 @@
+| Base | getName: | Base | getCanonicalType: | Base | getInterfaceType: | Base | hasSuperclass: | no | getNumberOfProtocols: | 1 |
+| Base | getName: | Base | getCanonicalType: | Base | getInterfaceType: | Base | hasSuperclass: | no | getNumberOfProtocols: | 1 |
 | Param | getName: | Param | getCanonicalType: | Param | getInterfaceType: | Param | hasSuperclass: | no | getNumberOfProtocols: | 0 |
 | ParamWithProtocols | getName: | ParamWithProtocols | getCanonicalType: | ParamWithProtocols | getInterfaceType: | ParamWithProtocols | hasSuperclass: | no | getNumberOfProtocols: | 2 |
 | ParamWithSuperclass | getName: | ParamWithSuperclass | getCanonicalType: | ParamWithSuperclass | getInterfaceType: | ParamWithSuperclass | hasSuperclass: | yes | getNumberOfProtocols: | 0 |

swift/ql/test/extractor-tests/generated/type/PrimaryArchetypeType/PrimaryArchetypeType_getProtocol.expected

@@ -1,3 +1,5 @@
+| Base | 0 | primary_archetypes.swift:3:1:3:13 | P |
+| Base | 0 | primary_archetypes.swift:4:1:4:14 | P2 |
 | ParamWithProtocols | 0 | file://:0:0:0:0 | Equatable |
 | ParamWithProtocols | 1 | primary_archetypes.swift:3:1:3:13 | P |
 | ParamWithSuperclassAndProtocols | 0 | file://:0:0:0:0 | Equatable |

swift/ql/test/extractor-tests/generated/type/PrimaryArchetypeType/primary_archetypes.swift

@@ -1,9 +1,19 @@
 class S {}
 
 protocol P {}
+protocol P2 {}
 
 func foo<Param,
          ParamWithSuperclass: S,
          ParamWithProtocols: P & Equatable,
          ParamWithSuperclassAndProtocols: S & Equatable & P>(
   _: Param, _: ParamWithSuperclass, _: ParamWithProtocols, _: ParamWithSuperclassAndProtocols) {}
+
+class Generic<Base> {}
+extension Generic where Base : P {
+  func f(_: Base) {}
+}
+
+extension Generic where Base : P2 {
+  func f(_: Base) {}
+}