Correctly put typeParameters on FunctionExpression (#585)

Author: danez

src/plugins/estree.js

@@ -152,12 +152,14 @@ export default function (instance) {
     };
   });
 
-  instance.extend("parseClassMethod", function (inner) {
-    return function (classBody, ...args) {
-      inner.call(this, classBody, ...args);
-
-      const body = classBody.body;
-      body[body.length - 1].type = "MethodDefinition";
+  instance.extend("parseClassMethod", function () {
+    return function (classBody, method, isGenerator, isAsync) {
+      this.parseMethod(method, isGenerator, isAsync);
+      if (method.typeParameters) {
+        method.value.typeParameters = method.typeParameters;
+        delete method.typeParameters;
+      }
+      classBody.body.push(this.finishNode(method, "MethodDefinition"));
     };
   });
 

test/fixtures/estree/class-method/flow/actual.js

@@ -0,0 +1,5 @@
+class NodeUtils extends UtilParser {
+  finishNodeAt<T : NodeType>(node: T): T {
+    return node;
+  }
+}