fix: fix error with other cases (#412)

Author: HsuTing

src/rules/useFlowType.js

@@ -36,8 +36,14 @@ const create = (context) => {
     TypeParameterDeclaration (node) {
       node.params.forEach((param) => {
         if (param.default && param.default.typeParameters) {
+          if (param.default.type === 'GenericTypeAnnotation') {
+            markTypeAsUsedWithGenericType(param.default);
+          }
+
           param.default.typeParameters.params.forEach((typeParameterNode) => {
-            markTypeAsUsedWithGenericType(typeParameterNode);
+            if (typeParameterNode.type === 'GenericTypeAnnotation') {
+              markTypeAsUsedWithGenericType(typeParameterNode);
+            }
           });
         }
       });

tests/rules/assertions/useFlowType.js

@@ -40,6 +40,12 @@ const VALID_WITH_USE_FLOW_TYPE = [
     errors: [
       '\'A\' is defined but never used.'
     ]
+  },
+  {
+    code: 'import type A from "a"; type X<B = A<string>> = { b: B }; let x: X; console.log(x);',
+    errors: [
+      '\'A\' is defined but never used.'
+    ]
   }
 ];