eslint-plugin-shopify

eslint-plugin-shopify

Shopify’s ESLint rules and configs.

Installation

You'll first need to install ESLint:

$ npm i eslint --save-dev

Next, install eslint-plugin-shopify:

$ npm install eslint-plugin-shopify --save-dev

Note: If you installed ESLint globally (using the -g flag) then you must also install eslint-plugin-shopify globally.

Usage

Shopify’s ESLint configs come bundled in this package. In order to use them, you simply extend the relevant configuration in your project’s .eslintrc. For example, the following will extend the ESNext (ES2015 and later) config:

{
  "extends": "plugin:shopify/esnext"
}

If using React, extend the React version of the configuration (which adds some React-specific rules to those in the ESNext config):

{
  "extends": "plugin:shopify/react"
}

If working on an ES5 project, extend the ES5 version of the configuration:

{
  "extends": "plugin:shopify/es5"
}

You can also add some "augmenting" configs on top of the "core" config by extending an array of linting configs. For example, this package provides a lodash linting config, which can be added to the ESNext config with the following configuration file:

{
  "extends": [
    "plugin:shopify/esnext",
    "plugin:shopify/lodash",
    "plugin:shopify/mocha"
  ]
}

Provided configurations

This plugin provides the following core configurations:

• esnext: Use this for anything written with ES2015+ features.
• react: Use this for React projects.
• es5: Use this for legacy projects.

This plugin also provides the following tool-specific configurations, which can be used on top of the core configurations:

• lodash: Use this for projects that use lodash.
• mocha: Use this for projects that use mocha/ sinon/ chai for testing.
• ava: Use this for projects that use the AVA test runner.
• flow: Use this for projects that use flow for type checking.
• jquery: Use this for projects that use jQuery.

node

If you are working on a node module, we also provide the node configuration for you. Note that this configuration needs to be used in conjunction with one of the core configurations (either es5 or esnext). If you plan to transpile your code using Babel, use the esnext config. If you do not plan to do so, the config you choose depends on the version of node you wish to support, and how many ESNext features are natively available in that version. You can see a detailed list of what version of node supports what new JavaScript features by visiting http://node.green.

A node project that will use Babel for transpilation would need the following ESLint config:

{
  "extends": [
    "plugin:shopify/esnext",
    "plugin:shopify/node"
  ]
}

Plugin-Provided Rules

This plugin provides the following custom rules, which are included as appropriate in all core linting configs:

• binary-assignment-parens: Requires (or disallows) assignments of binary, boolean-producing expressions to be wrapped in parentheses.
• class-property-semi: Requires (or disallows) semicolons for class properties.
• jquery-dollar-sign-reference: Requires that all jQuery objects are assigned to references prefixed with $.
• no-useless-computed-properties: Prevents the usage of unnecessary computed properties.
• prefer-class-properties: Prefer class properties to assignment of literals in constructors.
• prefer-early-return: Prefer early returns over full-body conditional wrapping in function declarations.
• require-flow: Requires (or disallows) @flow declarations be present at the top of each file.
• restrict-full-import: Prevents importing the entirety of a package.
• sinon-no-restricted-features: Restricts the use of specified sinon features.
• sinon-prefer-meaningful-assertions: Requires the use of meaningful sinon assertions through sinon.assert or sinon-chai.

Creating New Rules

The easiest way to add new rules is to use the ESLint Yeoman generator. Running yo eslint:rule from the root of this project should add the required main file, docs, and test for your new rules. Make sure that these are all filled out and consistent with the other rules before merging. All tests can be run using npm test.