feat(lint): Optionally use prettier with --prettier flag

README.md

@@ -340,13 +340,15 @@ Options
   --fix               Fixes fixable errors and warnings
   --ignore-pattern    Ignore a pattern
   --write-file        Write the config file locally
+  --prettier          Use Prettier to lint
   -h, --help          Displays this message
 
 Examples
-  $ tsdx lint src test
-  $ tsdx lint src test --fix
+  $ tsdx lint src
+  $ tsdx lint src --fix
   $ tsdx lint src test --ignore-pattern test/foobar.ts
-  $ tsdx lint src test --write-file
+  $ tsdx lint src --write-file
+  $ tsdx lint src test --prettier
 ```
 
 ## Author

package.json

@@ -24,7 +24,7 @@
     "prepare": "tsc -p tsconfig.json",
     "build": "tsc -p tsconfig.json",
     "lint": "yarn build && yarn lint:post-build",
-    "lint:post-build": "node dist/index.js lint src test --ignore-pattern 'test/tests/lint'",
+    "lint:post-build": "node dist/index.js lint src test --ignore-pattern 'test/tests/lint' --prettier",
     "test": "jest --config ./test/jest.config.json"
   },
   "files": [
@@ -50,6 +50,8 @@
     "cross-env": "5.2.0",
     "enquirer": "^2.3.0",
     "eslint": "^5.16.0",
+    "eslint-config-prettier": "^4.3.0",
+    "eslint-plugin-prettier": "^3.1.0",
     "eslint-config-react-app": "^4.0.1",
     "eslint-plugin-flowtype": "^2.50.3",
     "eslint-plugin-import": "^2.17.3",
@@ -93,8 +95,6 @@
     "@types/react": "^16.8.17",
     "@types/rollup-plugin-json": "^3.0.2",
     "@types/rollup-plugin-sourcemaps": "^0.4.2",
-    "eslint-config-prettier": "^4.3.0",
-    "eslint-plugin-prettier": "^3.1.0",
     "husky": "^2.3.0",
     "prettier": "^1.17.1",
     "pretty-quick": "^1.10.0",

src/createEslintConfig.ts

@@ -3,15 +3,23 @@ import path from 'path';
 import { CLIEngine } from 'eslint';
 
 interface CreateEslintConfigArgs {
+  prettier: boolean;
   rootDir: string;
   writeFile: boolean;
 }
 export function createEslintConfig({
+  prettier,
   rootDir,
   writeFile,
 }: CreateEslintConfigArgs): CLIEngine.Options['baseConfig'] {
+  const baseExtends = ['react-app'];
   const config = {
-    extends: ['react-app'],
+    extends: prettier
+      ? baseExtends.concat([
+          'prettier/@typescript-eslint',
+          'plugin:prettier/recommended',
+        ])
+      : baseExtends,
   };
 
   if (writeFile) {

src/index.ts

@@ -406,9 +406,12 @@ prog
   .example('lint src test --ignore-pattern test/foobar.ts')
   .option('--write-file', 'Write the config file locally')
   .example('lint src test --write-file')
+  .option('--prettier', 'Use Prettier to lint')
+  .example('lint src test --prettier')
   .action(
     async (opts: {
       fix: boolean;
+      prettier: boolean;
       'ignore-pattern': string;
       'write-file': boolean;
       _: string[];
@@ -419,6 +422,7 @@ prog
         ignorePattern: opts['ignore-pattern'],
         baseConfig: {
           ...createEslintConfig({
+            prettier: opts.prettier,
             rootDir: paths.appRoot,
             writeFile: opts['write-file'],
           }),

test/tests/lint/file-with-lint-errors.ts

@@ -1,4 +1 @@
-export const foo  = (   ) => 
-!! ('bar')
-;
-
+export const foo () => !!'bar';

test/tests/lint/file-with-prettier-lint-errors.ts

@@ -0,0 +1,5 @@
+export const foo  = (   ) => 
+!! ('bar')
+;
+
+

test/tests/lint/react-file-with-lint-errors.tsx

@@ -1,6 +1,6 @@
 import React from 'react';
 
-export const Foobar = (props: any  ) => {
+export const Foobar (props: any  ) => {
   return <div {...props
   }  >foobar</div>;
 }

test/tests/lint/tsdx-lint.test.js

@@ -20,6 +20,21 @@ describe('tsdx lint', () => {
     expect(output.code).toBe(0);
   });
 
+  describe('prettier', () => {
+    const flags = '--prettier'
+    it('should fail to lint a ts file with errors', () => {
+      const testFile = 'test/tests/lint/file-with-prettier-lint-errors.ts';
+      const output = shell.exec(`node dist/index.js lint ${testFile} ${flags}`);
+      expect(output.code).toBe(1);
+    });
+
+    it('should succeed linting a ts file without errors', () => {
+      const testFile = 'test/tests/lint/file-without-lint-error.ts';
+      const output = shell.exec(`node dist/index.js lint ${testFile} ${flags}`);
+      expect(output.code).toBe(0);
+    });
+  })
+
   it('should fail to lint a tsx file with errors', () => {
     const testFile = 'test/tests/lint/react-file-with-lint-errors.tsx';
     const output = shell.exec(`node dist/index.js lint ${testFile}`);