Update meow dependency (#41)

* refactor: update source to ES modules

Update the source code from CommonJS to ES Modules style. This consists
of changing `require`s to `import from` statements, `module.exports` to
`export` statements, and in some cases the structure of imports and
exports as well. Notably when the old `require` statement also contained
some additional logic, which is not possible with import statements.

* chore(deps): update meow from ^3.7.0 to ^10.1.1

Update the meow dependency to ^10.1.1 - which is the latest version -
and update how it is used in accordance with breaking changes.

* refactor: update tests to ES modules

* chore: update package manifest

Update the exports field for exporting ESM and CJS and set package
type to "module".

* docs: update JS API example

* docs: update config example to use ESM syntax

* ci: run tests on Node v12, v14, v16, and v17

* chore: make svglint config file an ESM

* fix: loading config files and built-in rules on Windows

Use the `"file://"` prefix when loading CLI config and rules to ensure
importing always works on Windows.

* ci: run CLI on various node versions and operating systems

* feat: add CJS version of Node API

Add a CommonJS version of the Node API of SVGLint by building it using
Rollup. Update the package manifest to allow for importing/requiring ESM
and CJS (resp.) and `.gitignore` to ignore the generated CJS file.

One "custom" Rollup plugin (provided by Rollup but not included by
default) is used, namely `plugin-dynamic-import-vars`. This plugin
ensures that dynamic imports are properly handled as the CJS output
generated by Rollup cannot dynamically import ESM rules. To make this
work the rule-loader had to be updated as well, unfortunately the
requirements of this plugin are quite strict and it is required that the
`"../rules"` path is hardcoded into the `import` statement. Furthermore
it has trouble detecting things that should be ignored, so errors are
disabled to prevent errors due to dynamic imports of external plugins.

* chore: add .npmrc to enforce `engine-strict` option

BREAKING CHANGE: Minimum node version increased to `^12.20.0` or
`^14.13.1` or `>=16.0.0`.
BREAKING CHANGE: The Node API is now fully `async`.

.eslintrc.js → .eslintrc.cjs

@@ -4,6 +4,10 @@ module.exports = {
         "es6": true,
         "jasmine": true
     },
+    "parserOptions": {
+        "sourceType": "module",
+        "ecmaVersion": 2020,
+    },
     "extends": "eslint:recommended",
     "rules": {
         "indent": ["error", 4, { "SwitchCase": 1 }],

.github/workflows/test.yml

@@ -5,6 +5,16 @@ jobs:
   test:
     name: Run tests
     runs-on: ubuntu-18.04
+    strategy:
+      matrix:
+        node-version:
+          - 12.20.0
+          - 14.13.1
+          - 16.0.0
+          - 12
+          - 14
+          - 16
+          - 17
     steps:
       - name: Checkout
         uses: actions/checkout@v2
@@ -13,10 +23,31 @@ jobs:
       - name: Node.js setup
         uses: actions/setup-node@v1
         with:
-          node-version: 12
+          node-version: ${{ matrix.node-version }}
       - name: Install dependencies
         run: npm ci
       - name: Lint
         run: npm run lint
       - name: Test
         run: npm test
+      - name: Run CLI
+        run: node ./bin/cli.js test/svgs/attr.test.svg
+  test-cli:
+    name: Run CLI
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [macos-latest, ubuntu-latest, windows-latest]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+      - name: Node.js setup
+        uses: actions/setup-node@v1
+        with:
+          node-version: 16
+      - name: Install dependencies
+        run: npm ci
+      - name: Run CLI
+        run: node ./bin/cli.js test/svgs/attr.test.svg

.gitignore

@@ -1,2 +1,3 @@
 node_modules
 .vscode
+src/svglint.cjs

.npmrc

@@ -0,0 +1 @@
+engine-strict=true

.svglintrc.js

@@ -1,4 +1,4 @@
-module.exports = {
+export default {
     rules: {
         attr: {
             "rule::selector": "path",

README.md

@@ -31,8 +31,9 @@ $ svglint --help
 The tool can also be used through the JS API.
 
 ```javascript
-const SVGLint = require("svglint");
-const linting = SVGLint.lintSource("<svg>...</svg>", {
+import SVGLint from "svglint";
+
+const linting = await SVGLint.lintSource("<svg>...</svg>", {
     // ... config goes here
 });
 linting.on("done", () => {
@@ -50,7 +51,7 @@ If you are using the CLI, this configuration object is read from the file specif
 This configuration file should export a single object, of the format:
 
 ```javascript
-module.exports = {
+export default {
     // additional configuration may go here in the future
     // for now, "rules" is the only useful key
     rules: {
@@ -66,7 +67,7 @@ module.exports = {
             function() { // config 1 for the "custom" rule }
         ]
     }
-};
+}
 ```
 
 For specifics on how the config for each rule should be formatted, see [their specific rule files](https://github.com/birjolaxew/svglint/tree/master/src/rules).

bin/cli.js

@@ -3,16 +3,18 @@
  * @fileoverview The CLI that is executed from a terminal.
  * Acts as an interface to the JS API
  */
-const path = require("path");
-const GUI = new (require("../src/cli/gui"));
-const Logger = require("../src/lib/logger");
-const SVGLint = require("../src/svglint");
+import path from "path";
+import gui from "../src/cli/gui.js";
+import Logger from "../src/lib/logger.js";
+import SVGLint from "../src/svglint.js";
 // @ts-ignore
-const meta = require("../package.json");
-const { getConfigurationFile } = require("../src/cli/config");
-const meow = require("meow");
-const chalk = require("chalk");
-const glob = require("glob");
+import config from "../src/cli/config.js";
+import meow from "meow";
+import chalk from "chalk";
+import glob from "glob";
+
+const GUI = new gui();
+const { getConfigurationFile } = config;
 
 const logger = Logger("");
 // Pretty logs all errors, then exits
@@ -23,10 +25,7 @@ process.on("uncaughtException", err => {
 });
 
 // Generates the CLI binding using meow
-const cli = meow({
-    description: meta.description,
-    version: meta.version,
-    help: `
+const cli = meow(`
         ${chalk.yellow("Usage:")}
             ${chalk.bold("svglint")} [--config config.js] [--ci] [--debug] ${chalk.bold("file1.svg file2.svg")}
 
@@ -35,7 +34,8 @@ const cli = meow({
             ${chalk.bold("--version")}     Show the current SVGLint version
             ${chalk.bold("--config, -c")}  Specify the config file. Defaults to '.svglintrc.js'
             ${chalk.bold("--debug,  -d")}  Show debug logs
-            ${chalk.bold("--ci, -C")}      Only output to stdout once, when linting is finished`,
+            ${chalk.bold("--ci, -C")}      Only output to stdout once, when linting is finished`, {
+    importMeta: import.meta,
     flags: {
         config: { type: "string", alias: "c", },
         debug: { type: "boolean", alias: "d" },
@@ -62,7 +62,8 @@ process.on("exit", () => {
     try {
         const configFile = await getConfigurationFile(cli.flags.config);
         if (configFile) {
-            configObj = require(configFile);
+            const module = await import(`file://${configFile}`);
+            configObj = module.default;
         } else {
             logger.debug("No configuration file found")
             if (cli.flags.config) {