feat: improved validation error messages

.github/CONTRIBUTING.md

@@ -147,6 +147,14 @@ module. Thankfully, Github provides a means to do this. Add a dependency to the
 
 Where `{id}` is the # ID of your Pull Request.
 
+## Contributor License Agreement
+
+When submitting your contribution, a CLA (Contributor License Agreement) bot will come by to verify that you signed the [CLA](https://cla.js.foundation/webpack-contrib/css-loader).
+If it is your first time, it will link you to the right place to sign it.
+However, if you have committed your contributions using an email that is not the same as your email used on GitHub, the CLA bot can't accept your contribution.
+
+Run `git config user.email` to see your Git email, and verify it with [your GitHub email](https://github.com/settings/emails).
+
 ## Thanks
 
 For your interest, time, understanding, and for following this simple guide.

README.md

@@ -109,21 +109,22 @@ module.exports = {
 
 ## Options
 
-|                    Name                     |            Type             | Default | Description                                        |
-| :-----------------------------------------: | :-------------------------: | :-----: | :------------------------------------------------- |
-|              **[`url`](#url)**              |    `{Boolean\|Function}`    | `true`  | Enable/Disable `url()` handling                    |
-|           **[`import`](#import)**           |    `{Boolean\|Function}`    | `true`  | Enable/Disable @import handling                    |
-|          **[`modules`](#modules)**          | `{Boolean\|String\|Object}` | `false` | Enable/Disable CSS Modules and setup their options |
-|        **[`sourceMap`](#sourcemap)**        |         `{Boolean}`         | `false` | Enable/Disable Sourcemaps                          |
-|    **[`importLoaders`](#importloaders)**    |         `{Number}`          |   `0`   | Number of loaders applied before CSS loader        |
-| **[`localsConvention`](#localsconvention)** |         `{String}`          | `asIs`  | Setup style of exported classnames                 |
-|       **[`onlyLocals`](#onlylocals)**       |         `{Boolean}`         | `false` | Export only locals                                 |
+|                    Name                     |            Type             | Default | Description                                                            |
+| :-----------------------------------------: | :-------------------------: | :-----: | :--------------------------------------------------------------------- |
+|              **[`url`](#url)**              |    `{Boolean\|Function}`    | `true`  | Enables/Disables `url`/`image-set` functions handling                  |
+|           **[`import`](#import)**           |    `{Boolean\|Function}`    | `true`  | Enables/Disables `@import` at-rules handling                           |
+|          **[`modules`](#modules)**          | `{Boolean\|String\|Object}` | `false` | Enables/Disables CSS Modules and their configuration                   |
+|        **[`sourceMap`](#sourcemap)**        |         `{Boolean}`         | `false` | Enables/Disables generation of source maps                             |
+|    **[`importLoaders`](#importloaders)**    |         `{Number}`          |   `0`   | Enables/Disables or setups number of loaders applied before CSS loader |
+| **[`localsConvention`](#localsconvention)** |         `{String}`          | `asIs`  | Style of exported classnames                                           |
+|       **[`onlyLocals`](#onlylocals)**       |         `{Boolean}`         | `false` | Export only locals                                                     |
 
 ### `url`
 
 Type: `Boolean|Function`
 Default: `true`
 
+Enables/Disables `url`/`image-set` functions handling.
 Control `url()` resolving. Absolute URLs and root-relative URLs are not resolving.
 
 Examples resolutions:
@@ -203,6 +204,7 @@ module.exports = {
 Type: `Boolean`
 Default: `true`
 
+Enables/Disables `@import` at-rules handling.
 Control `@import` resolving. Absolute urls in `@import` will be moved in runtime code.
 
 Examples resolutions:
@@ -285,6 +287,8 @@ module.exports = {
 Type: `Boolean|String|Object`
 Default: `false`
 
+Enables/Disables CSS Modules and their configuration.
+
 The `modules` option enables/disables the **[CSS Modules](https://github.com/css-modules/css-modules)** specification and setup basic behaviour.
 
 Using `false` value increase performance because we avoid parsing **CSS Modules** features, it will be useful for developers who use vanilla css or use other technologies.
@@ -703,14 +707,12 @@ module.exports = {
 Type: `Boolean`
 Default: `false`
 
-To include source maps set the `sourceMap` option.
+Enables/Disables generation of source maps.
 
-I.e. the `mini-css-extract-plugin` can handle them.
+To include source maps set the `sourceMap` option.
 
 They are not enabled by default because they expose a runtime overhead and increase in bundle size (JS source maps do not).
 
-In addition to that relative paths are buggy and you need to use an absolute public path which includes the server URL.
-
 **webpack.config.js**
 
 ```js
@@ -734,6 +736,8 @@ module.exports = {
 Type: `Number`
 Default: `0`
 
+Enables/Disables or setups number of loaders applied before CSS loader.
+
 The option `importLoaders` allows you to configure how many loaders before `css-loader` should be applied to `@import`ed resources.
 
 **webpack.config.js**
@@ -749,7 +753,10 @@ module.exports = {
           {
             loader: 'css-loader',
             options: {
-              importLoaders: 2, // 0 => no loaders (default); 1 => postcss-loader; 2 => postcss-loader, sass-loader
+              importLoaders: 2,
+              // 0 => no loaders (default);
+              // 1 => postcss-loader;
+              // 2 => postcss-loader, sass-loader
             },
           },
           'postcss-loader',
@@ -768,6 +775,8 @@ This may change in the future when the module system (i. e. webpack) supports lo
 Type: `String`
 Default: `undefined`
 
+Style of exported classnames.
+
 By default, the exported JSON keys mirror the class names (i.e `asIs` value).
 
 |         Name          |    Type    | Description                                                                                      |
@@ -814,7 +823,9 @@ module.exports = {
 Type: `Boolean`
 Default: `false`
 
-Export only locals (**useful** when you use **css modules**).
+Export only locals.
+
+**Useful** when you use **css modules** for pre-rendering (for example SSR).
 For pre-rendering with `mini-css-extract-plugin` you should use this option instead of `style-loader!css-loader` **in the pre-rendering bundle**.
 It doesn't embed CSS but only exports the identifier mappings.
 

lint-staged.config.js

@@ -1,7 +1,4 @@
 module.exports = {
-  ignore: ['package-lock.json', 'CHANGELOG.md'],
-  linters: {
-    '*.js': ['prettier --write', 'eslint --fix', 'git add'],
-    '*.{json,md,yml,css}': ['prettier --write', 'git add'],
-  },
+  '*.js': ['prettier --write', 'eslint --fix', 'git add'],
+  '*.{json,md,yml,css}': ['prettier --write', 'git add'],
 };