From b27c80d9aba8d68d158414350db9b1047dbabf52 Mon Sep 17 00:00:00 2001
From: Simen Bekkhus <sbekkhus91@gmail.com>
Date: Mon, 22 Jul 2019 18:05:39 +0200
Subject: [PATCH] fix: prefer `hasOwnProperty` over `in`

Fixes #334
---
 src/rules/__tests__/valid-describe.test.ts |  4 ++++
 src/rules/tsUtils.ts                       | 10 +++++-----
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/src/rules/__tests__/valid-describe.test.ts b/src/rules/__tests__/valid-describe.test.ts
index b5e2cd76e..66e299e55 100644
--- a/src/rules/__tests__/valid-describe.test.ts
+++ b/src/rules/__tests__/valid-describe.test.ts
@@ -38,6 +38,10 @@ ruleTester.run('valid-describe', rule, {
       test('bar', () => {})
     )
     `,
+    `
+    if (hasOwnProperty(obj, key)) {
+    }
+    `,
   ],
   invalid: [
     {
diff --git a/src/rules/tsUtils.ts b/src/rules/tsUtils.ts
index 5f28d7141..95f3c642c 100644
--- a/src/rules/tsUtils.ts
+++ b/src/rules/tsUtils.ts
@@ -166,7 +166,7 @@ export const isHook = (
 ): node is JestFunctionCallExpressionWithIdentifierCallee<HookName> => {
   return (
     node.callee.type === AST_NODE_TYPES.Identifier &&
-    node.callee.name in HookName
+    HookName.hasOwnProperty(node.callee.name)
   );
 };
 
@@ -175,10 +175,10 @@ export const isTestCase = (
 ): node is JestFunctionCallExpression<TestCaseName> => {
   return (
     (node.callee.type === AST_NODE_TYPES.Identifier &&
-      node.callee.name in TestCaseName) ||
+      TestCaseName.hasOwnProperty(node.callee.name)) ||
     (node.callee.type === AST_NODE_TYPES.MemberExpression &&
       node.callee.object.type === AST_NODE_TYPES.Identifier &&
-      node.callee.object.name in TestCaseName)
+      TestCaseName.hasOwnProperty(node.callee.object.name))
   );
 };
 
@@ -187,10 +187,10 @@ export const isDescribe = (
 ): node is JestFunctionCallExpression<DescribeAlias> => {
   return (
     (node.callee.type === AST_NODE_TYPES.Identifier &&
-      node.callee.name in DescribeAlias) ||
+      DescribeAlias.hasOwnProperty(node.callee.name)) ||
     (node.callee.type === AST_NODE_TYPES.MemberExpression &&
       node.callee.object.type === AST_NODE_TYPES.Identifier &&
-      node.callee.object.name in DescribeAlias)
+      DescribeAlias.hasOwnProperty(node.callee.object.name))
   );
 };