Fix: Fixed hexists edge cases (#331)

* Adding edge cases to hexists tests

* Adding edge cases to hexists

* Forgot to add imports

* Make linter happy

* Update CHANGELOG.md

CHANGELOG.md

@@ -5,6 +5,8 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+### Fixes
+* Fixed hexists edge cases (#331 @wraytw) 
 
 ## [3.1.0] - 2017-10-03
 ### Features

src/commands/hexists.js

@@ -1,3 +1,7 @@
 export function hexists(key, field) {
-  return {}.hasOwnProperty.call(this.data.get(key), field) ? 1 : 0;
+  const hash = this.data.get(key);
+  if (!hash || hash[field] === undefined) {
+    return 0;
+  }
+  return {}.hasOwnProperty.call(hash, field) ? 1 : 0;
 }

test/commands/hexists.js

@@ -3,15 +3,27 @@ import expect from 'expect';
 import MockRedis from '../../src';
 
 describe('hexists', () => {
-  const redis = new MockRedis({
-    data: {
-      foo: { bar: 'baz' },
-    },
+  context('hash exists', () => {
+    const redis = new MockRedis({
+      data: {
+        foo: { bar: 'baz' },
+      },
+    });
+
+    it('should return 1 if key exists in hash map', () =>
+      redis.hexists('foo', 'bar').then(status => expect(status).toBe(1))
+    );
+
+    it('should return 0 if key not exists in hash map', () =>
+      redis.hexists('foo', 'baz').then(status => expect(status).toBe(0))
+    );
+  });
+
+  context('hash doesn\'t exist', () => {
+    const redis = new MockRedis();
+
+    it('should return 0', () =>
+      redis.hexists('foo', 'baz').then(status => expect(status).toBe(0))
+    );
   });
-  it('should return 1 if key exists in hash map', () =>
-    redis.hexists('foo', 'bar').then(status => expect(status).toBe(1))
-  );
-  it('should return 0 if key not exists in hash map', () =>
-    redis.hexists('foo', 'baz').then(status => expect(status).toBe(0))
-  );
 });