Scripts: Add support for lint-pkg-json script

package.json

@@ -56,7 +56,7 @@
 		"check-engines": "check-node-version --package",
 		"create-symlinks": "node ./scripts/create-symlinks.js",
 		"lerna-bootstrap": "lerna bootstrap --hoist",
-		"lint:pkg-json": "npmPkgJsonLint ./packages",
+		"lint:pkg-json": "wp-scripts lint-pkg-json ./packages",
 		"postinstall": "npm-run-all lerna-bootstrap create-symlinks build",
 		"pretest": "npm run lint:pkg-json",
 		"test": "wp-scripts test-unit-js",

packages/scripts/README.md

@@ -30,6 +30,10 @@ This is how you execute those scripts using the presented setup:
 
 ## Available Scripts
 
+### `wp-scripts lint-pkg-json`
+
+Helps enforce standards for your package.json file. It uses [npm-package-json-lint](https://www.npmjs.com/package/npm-package-json-lint) with the set of default rules provided. You can override them with your own rules as described in [npm-package-json-lint wiki](https://github.com/tclindner/npm-package-json-lint/wiki).
+
 ### `wp-scripts test-unit-js`
 
 _Alias_: `wp-scripts test-unit-jest` 

packages/scripts/config/npmpackagejsonlint.json

@@ -0,0 +1,3 @@
+{
+	"extends": "@wordpress/npm-package-json-lint-config"
+}

packages/scripts/package.json

@@ -33,9 +33,11 @@
 	"dependencies": {
 		"@wordpress/babel-preset-default": "^1.3.0",
 		"@wordpress/jest-preset-default": "^1.0.6",
+		"@wordpress/npm-package-json-lint-config": "^1.0.0",
 		"cross-spawn": "^5.1.0",
 		"jest": "^22.4.0",
-		"read-pkg-up": "^3.0.0"
+		"read-pkg-up": "^3.0.0",
+		"resolve-bin": "^0.4.0"
 	},
 	"publishConfig": {
 		"access": "public"

packages/scripts/scripts/lint-pkg-json.js

@@ -0,0 +1,36 @@
+/**
+ * External dependencies
+ */
+const { sync: spawn } = require( 'cross-spawn' );
+const { sync: resolveBin } = require( 'resolve-bin' );
+
+/**
+ * Internal dependencies
+ */
+const {
+	fromConfigRoot,
+	getCliArgs,
+	hasCliArg,
+	hasProjectFile,
+	hasPackageProp,
+} = require( '../utils' );
+
+const args = getCliArgs();
+
+const hasLintConfig = hasCliArg( '-c' ) ||
+	hasCliArg( '--configFile' ) ||
+	hasProjectFile( '.npmpackagejsonlintrc.json' ) ||
+	hasProjectFile( 'npmpackagejsonlint.config.js' ) ||
+	hasPackageProp( 'npmPackageJsonLintConfig' );
+
+const config = ! hasLintConfig
+	? [ '--configFile', fromConfigRoot( 'npmpackagejsonlint.json' ) ]
+	: [];
+
+const result = spawn(
+	resolveBin( 'npm-package-json-lint', { executable: 'npmPkgJsonLint' } ),
+	[ ...config, ...args ],
+	{ stdio: 'inherit' }
+);
+
+process.exit( result.status );

packages/scripts/utils/index.js

@@ -22,6 +22,9 @@ const fromProjectRoot = ( fileName ) =>
 const hasProjectFile = ( fileName ) =>
 	existsSync( fromProjectRoot( fileName ) );
 
+const fromConfigRoot = ( fileName ) =>
+	path.join( path.dirname( __dirname ), 'config', fileName );
+
 const fromScriptsRoot = ( scriptName ) =>
 	path.join( path.dirname( __dirname ), 'scripts', `${ scriptName }.js` );
 
@@ -74,6 +77,7 @@ const spawnScript = ( scriptName, args = [] ) => {
 };
 
 module.exports = {
+	fromConfigRoot,
 	getCliArgs,
 	hasCliArg,
 	hasProjectFile,

packages/scripts/utils/package.js

@@ -2,14 +2,14 @@
  * External dependencies
  */
 const { realpathSync } = require( 'fs' );
-const readPkgUp = require( 'read-pkg-up' );
+const { sync: readPkgUp } = require( 'read-pkg-up' );
 
 /**
  * Internal dependencies
  */
 const { getCurrentWorkingDirectory } = require( './process' );
 
-const { pkg, path: pkgPath } = readPkgUp.sync( {
+const { pkg, path: pkgPath } = readPkgUp( {
 	cwd: realpathSync( getCurrentWorkingDirectory() ),
 } );