feat: add fixer for lowercase-name rule (#119)

Fixes #118

Author: macklinu

README.md

@@ -81,7 +81,7 @@ for more information about extending configuration files.
 | Rule                                                               | Description                                                       | Recommended                                                             | Fixable                                                      |
 | ------------------------------------------------------------------ | ----------------------------------------------------------------- | ----------------------------------------------------------------------- | ------------------------------------------------------------ |
 | [consistent-test-it](docs/rules/consistent-test-it.md)             | Enforce consistent test or it keyword                             |                                                                         | ![fixable](https://img.shields.io/badge/-fixable-green.svg)  |
-| [lowercase-name](docs/rules/lowercase-name.md)                     | Disallow capitalized test names                                   |                                                                         |                                                              |
+| [lowercase-name](docs/rules/lowercase-name.md)                     | Disallow capitalized test names                                   |                                                                         | ![fixable](https://img.shields.io/badge/-fixable-green.svg)  |
 | [no-disabled-tests](docs/rules/no-disabled-tests.md)               | Disallow disabled tests                                           | ![recommended](https://img.shields.io/badge/-recommended-lightgrey.svg) |                                                              |
 | [no-focused-tests](docs/rules/no-focused-tests.md)                 | Disallow focused tests                                            | ![recommended](https://img.shields.io/badge/-recommended-lightgrey.svg) |                                                              |
 | [no-hooks](docs/rules/no-hooks.md)                                 | Disallow setup and teardown hooks                                 |                                                                         |                                                              |

rules/__tests__/lowercase-name.test.js

@@ -21,13 +21,15 @@ ruleTester.run('lowercase-name', rule, {
     'it("<Foo/>", function () {})',
     'it("123 foo", function () {})',
     'it(42, function () {})',
+    'it(``)',
     'test()',
     "test('foo', function () {})",
     'test("foo", function () {})',
     'test(`foo`, function () {})',
     'test("<Foo/>", function () {})',
     'test("123 foo", function () {})',
     'test("42", function () {})',
+    'test(``)',
     'describe()',
     "describe('foo', function () {})",
     'describe("foo", function () {})',
@@ -36,11 +38,13 @@ ruleTester.run('lowercase-name', rule, {
     'describe("123 foo", function () {})',
     'describe("42", function () {})',
     'describe(function () {})',
+    'describe(``)',
   ],
 
   invalid: [
     {
       code: "it('Foo', function () {})",
+      output: "it('foo', function () {})",
       errors: [
         {
           message: '`it`s should begin with lowercase',
@@ -51,6 +55,7 @@ ruleTester.run('lowercase-name', rule, {
     },
     {
       code: 'it("Foo", function () {})',
+      output: 'it("foo", function () {})',
       errors: [
         {
           message: '`it`s should begin with lowercase',
@@ -61,6 +66,7 @@ ruleTester.run('lowercase-name', rule, {
     },
     {
       code: 'it(`Foo`, function () {})',
+      output: 'it(`foo`, function () {})',
       errors: [
         {
           message: '`it`s should begin with lowercase',
@@ -71,6 +77,7 @@ ruleTester.run('lowercase-name', rule, {
     },
     {
       code: "test('Foo', function () {})",
+      output: "test('foo', function () {})",
       errors: [
         {
           message: '`test`s should begin with lowercase',
@@ -81,6 +88,7 @@ ruleTester.run('lowercase-name', rule, {
     },
     {
       code: 'test("Foo", function () {})',
+      output: 'test("foo", function () {})',
       errors: [
         {
           message: '`test`s should begin with lowercase',
@@ -91,6 +99,7 @@ ruleTester.run('lowercase-name', rule, {
     },
     {
       code: 'test(`Foo`, function () {})',
+      output: 'test(`foo`, function () {})',
       errors: [
         {
           message: '`test`s should begin with lowercase',
@@ -101,6 +110,7 @@ ruleTester.run('lowercase-name', rule, {
     },
     {
       code: "describe('Foo', function () {})",
+      output: "describe('foo', function () {})",
       errors: [
         {
           message: '`describe`s should begin with lowercase',
@@ -111,6 +121,7 @@ ruleTester.run('lowercase-name', rule, {
     },
     {
       code: 'describe("Foo", function () {})',
+      output: 'describe("foo", function () {})',
       errors: [
         {
           message: '`describe`s should begin with lowercase',
@@ -121,6 +132,18 @@ ruleTester.run('lowercase-name', rule, {
     },
     {
       code: 'describe(`Foo`, function () {})',
+      output: 'describe(`foo`, function () {})',
+      errors: [
+        {
+          message: '`describe`s should begin with lowercase',
+          column: 1,
+          line: 1,
+        },
+      ],
+    },
+    {
+      code: 'describe(`Some longer description`, function () {})',
+      output: 'describe(`some longer description`, function () {})',
       errors: [
         {
           message: '`describe`s should begin with lowercase',

rules/lowercase-name.js

@@ -52,6 +52,7 @@ module.exports = {
     docs: {
       url: getDocsUrl(__filename),
     },
+    fixable: 'code',
   },
   create(context) {
     const ignore = (context.options[0] && context.options[0].ignore) || [];
@@ -72,6 +73,22 @@ module.exports = {
             message: '`{{ method }}`s should begin with lowercase',
             data: { method: erroneousMethod },
             node,
+            fix(fixer) {
+              const firstArg = node.arguments[0];
+              const description = testDescription(node);
+
+              const rangeIgnoringQuotes = [
+                firstArg.start + 1,
+                firstArg.end - 1,
+              ];
+              const newDescription =
+                description.substring(0, 1).toLowerCase() +
+                description.substring(1);
+
+              return [
+                fixer.replaceTextRange(rangeIgnoringQuotes, newDescription),
+              ];
+            },
           });
         }
       },