From e584243d60f12a76c98c485c9cfa204efce6ade9 Mon Sep 17 00:00:00 2001
From: Anders Hejlsberg <andersh@microsoft.com>
Date: Tue, 3 Apr 2018 09:04:24 -0700
Subject: [PATCH] Only look up identifiers that could actually be type
 parameters

---
 src/compiler/checker.ts | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 1e6a16aa75f..2e4937c95aa 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -9106,6 +9106,11 @@ namespace ts {
             return type;
         }
 
+        function maybeTypeParameterReference(node: Node) {
+            return !(node.kind === SyntaxKind.QualifiedName ||
+                node.parent.kind === SyntaxKind.TypeReference && (<TypeReferenceNode>node.parent).typeArguments && node === (<TypeReferenceNode>node.parent).typeName);
+        }
+
         function isTypeParameterPossiblyReferenced(tp: TypeParameter, node: Node) {
             // If the type parameter doesn't have exactly one declaration, if there are invening statement blocks
             // between the node and the type parameter declaration, if the node contains actual references to the
@@ -9122,7 +9127,8 @@ namespace ts {
                     case SyntaxKind.ThisType:
                         return tp.isThisType;
                     case SyntaxKind.Identifier:
-                        return !tp.isThisType && isPartOfTypeNode(node) && getTypeFromTypeNode(<TypeNode>node) === tp;
+                        return !tp.isThisType && isPartOfTypeNode(node) && maybeTypeParameterReference(node) &&
+                            getTypeFromTypeNode(<TypeNode>node) === tp;
                     case SyntaxKind.TypeQuery:
                         return true;
                 }