add _.endsWith and add tests for both endsWith and startsWith (#230)

README.md

@@ -166,11 +166,12 @@ then Lodash/Underscore is the better option.*
 
 **[String](#string)**
 
+1. [_.endsWith](#_endsWith)
 1. [_.padStart and _.padEnd](#_padstart-and-_padend)
 1. [_.repeat](#_repeat)
 1. [_.replace](#_replace)
 1. [_.split](#_split)
-1. [_.startsWith](#startsWith)
+1. [_.startsWith](#_startsWith)
 1. [_.template](#_template)
 1. [_.toLower](#_tolower)
 1. [_.toUpper](#_toupper)
@@ -2250,6 +2251,40 @@ Retrieves all the given object's own enumerable property values.
 
 ## String
 
+### _.endsWith
+:heavy_exclamation_mark:`Not in Underscore.js`
+Checks if string ends with the given target string.
+
+  ```js
+  // Lodash
+  _.endsWith('abc', 'c');
+  // => true
+
+  _.endsWith('abc', 'b');
+  // => false
+
+  _.endsWith('abc', 'b', 2);
+  // => true
+
+  // Native
+  'abc'.endsWith('c');
+  // => true
+
+  'abc'endsWith('b');
+  // => false
+
+  'abc'.endsWith('b', 2);
+  // => true
+  ```
+
+#### Browser Support for `String.prototype.endsWith()`
+
+![Chrome][chrome-image] | ![Edge][edge-image] | ![Firefox][firefox-image] | ![IE][ie-image] | ![Opera][opera-image] | ![Safari][safari-image]
+:-: | :-: | :-: | :-: | :-: | :-: |
+  41.0 ✔  |  ✔ | 17.0 ✔ |  ✖  |  28.0 ✔ |  9.0 ✔ |
+
+**[⬆ back to top](#quick-links)**
+
 ### _.padStart and _.padEnd
 :heavy_exclamation_mark:`Not in Underscore.js`
 Pads the current string with another string (multiple times, if needed) until the resulting string reaches the given length.

lib/rules/rules.json

@@ -219,9 +219,15 @@
         "alternative": "String.prototype.split()"
     },
     "startsWith": {
+        "ruleName": "starts-with",
         "compatible": true,
         "alternative": "String.prototype.startsWith()"
     },
+    "endsWith": {
+        "ruleName": "ends-with",
+        "compatible": true,
+        "alternative": "String.prototype.endsWith()"
+    },
     "toLower": {
         "compatible": true,
         "alternative": "String.prototype.toLowerCase()"

tests/lib/rules/all.js

@@ -157,4 +157,47 @@ ruleTester.run('_.flatten', rules['flatten'], {
   }]
 });
 
+ruleTester.run('_.isUndefined', rules['is-undefined'], {
+  valid: [
+    '2 === undefined'
+  ],
+  invalid: [{
+    code: '_.isUndefined(2)',
+    errors: ['Consider using the native value === undefined']
+  },{
+    code: '_(2).isUndefined()',
+    errors: ['Consider using the native value === undefined']
+
+  }]
+});
+
+ruleTester.run('_.startsWith', rules['starts-with'], {
+  valid: [
+    '"abc".startsWith("a")',
+    '"abc".startsWith("b", 1)'
+  ],
+  invalid: [{
+    code: '_.startsWith("abc", "a")',
+    errors: ['Consider using the native String.prototype.startsWith()']
+  },{
+    code: '_.startsWith("abc", "b", 1)',
+    errors: ['Consider using the native String.prototype.startsWith()']
+
+  }]
+});
+
+ruleTester.run('_.endsWith', rules['ends-with'], {
+  valid: [
+    '"abc".endsWith("c")',
+    '"abc".endsWith("b", 1)'
+  ],
+  invalid: [{
+    code: '_.endsWith("abc", "c")',
+    errors: ['Consider using the native String.prototype.endsWith()']
+  },{
+    code: '_.endsWith("abc", "b", 1)',
+    errors: ['Consider using the native String.prototype.endsWith()']
+
+  }]
+});
 

tests/unit/all.js

@@ -663,7 +663,6 @@ describe('code snippet example', () => {
       });
 
       assert.deepEqual(lodashOutput,nativeOutput);
-
     });
 
     it('_.forEach(object)', () => {
@@ -686,8 +685,48 @@ describe('code snippet example', () => {
       });
 
       assert.deepEqual(lodashOutput,nativeOutput);
+    });
+  });
 
+  describe('startsWith', () => {
+    it(`_.startsWith('abc', 'a')`, () => {
+      assert.deepEqual(
+        _.startsWith('abc', 'a'),
+        'abc'.startsWith('a')
+      );
+    });
+    it(`_.startsWith('abc', 'b')`, () => {
+      assert.deepEqual(
+        _.startsWith('abc', 'b'),
+        'abc'.startsWith('b')
+      );
+    });
+    it(`_.startsWith('abc', 'b', 1)`, () => {
+      assert.deepEqual(
+        _.startsWith('abc', 'b', 1),
+        'abc'.startsWith('b', 1)
+      );
     });
   });
 
-})
+  describe('endsWith', () => {
+    it(`_.endsWith('abc', 'c')`, () => {
+      assert.deepEqual(
+        _.endsWith('abc', 'c'),
+        'abc'.endsWith('c')
+      );
+    });
+    it(`_.endsWith('abc', 'b')`, () => {
+      assert.deepEqual(
+        _.endsWith('abc', 'b'),
+        'abc'.endsWith('b')
+      );
+    });
+    it(`_.endsWith('abc', 'b', 2)`, () => {
+      assert.deepEqual(
+        _.endsWith('abc', 'b', 2),
+        'abc'.endsWith('b', 2)
+      );
+    });
+  });
+});