ASTDemangler: Introduce new getTypeDeclForUSR()

Author: slavapestov

include/swift/AST/ASTDemangler.h

@@ -40,6 +40,9 @@ Type getTypeForMangling(ASTContext &ctx,
 TypeDecl *getTypeDeclForMangling(ASTContext &ctx,
                                  llvm::StringRef mangling);
 
+TypeDecl *getTypeDeclForUSR(ASTContext &ctx,
+                            llvm::StringRef usr);
+
 /// An implementation of MetadataReader's BuilderType concept that
 /// just finds and builds things in the AST.
 class ASTBuilder {

lib/AST/ASTDemangler.cpp

@@ -31,6 +31,7 @@
 #include "swift/AST/Types.h"
 #include "swift/ClangImporter/ClangImporter.h"
 #include "swift/Demangling/Demangler.h"
+#include "swift/Demangling/ManglingMacros.h"
 
 using namespace swift;
 
@@ -56,6 +57,17 @@ TypeDecl *swift::Demangle::getTypeDeclForMangling(ASTContext &ctx,
   return builder.createTypeDecl(node);
 }
 
+TypeDecl *swift::Demangle::getTypeDeclForUSR(ASTContext &ctx,
+                                             StringRef usr) {
+  if (!usr.startswith("s:"))
+    return nullptr;
+
+  std::string mangling(usr);
+  mangling.replace(0, 2, MANGLING_PREFIX_STR);
+
+  return getTypeDeclForMangling(ctx, mangling);
+}
+
 TypeDecl *ASTBuilder::createTypeDecl(NodePointer node) {
   if (node->getKind() == Node::Kind::Global)
     return createTypeDecl(node->getChild(0));