add addStylusLoader

api.md

@@ -30,6 +30,7 @@ This file documents the functions exported by `customize-cra`.
   - [setWebpackOptimizationSplitChunks](#setwebpackoptimizationsplitchunkstarget)
   - [adjustWorkbox](#adjustworkboxfn)
   - [addLessLoader](#addlessloaderloaderoptions)
+  - [addStylusLoader](#addstylusloaderloaderoptions)
   - [addPostcssPlugins](#addpostcsspluginsplugins)
   - [disableChunk](#disablechunk)
   - [removeModuleScopePlugin](#removemodulescopeplugin)
@@ -414,6 +415,59 @@ declare module "*.module.less" {
 }
 ```
 
+### addStylusLoader(loaderOptions)
+
+First, install `stylus` and `stylus-loader` packages:
+
+```bash
+yarn add --dev stylus stylus-loader
+```
+
+or:
+
+```bash
+npm i -D stylus stylus-loader
+```
+
+After it's done, call `addStylusLoader` in `override` like below:
+
+```js
+const { addStylusLoader } = require("customize-cra");
+
+module.exports = override(addStylusLoader(loaderOptions));
+```
+
+`loaderOptions` is optional. If you have Stylus specific options, you can pass to it. For example:
+
+```js
+const { addStylusLoader } = require("customize-cra");
+
+module.exports = override(
+  addStylusLoader({
+    stylusOptions: {}, // pass any options to stylus.
+    cssLoaderOptions: {}, // .styl file used css-loader option, not all CSS file.
+    cssModules: {
+      localIdentName: "[path][name]__[local]--[hash:base64:5]", // if you use CSS Modules, and custom `localIdentName`, default is '[local]--[hash:base64:5]'.
+    },
+  })
+);
+```
+
+Check [stylus-loader document](https://github.com/webpack-contrib/stylus-loader#options) and [stylus document](https://stylus-lang.com/docs/js.html) for all available specific options you can use.
+
+Once `stylus-loader` is enabled, you can import `.styl` file in your project.
+
+`.module.styl` will use CSS Modules.
+
+> if you use TypeScript (npm init react-app my-app --typescript) with CSS Modules, you should edit `react-app-env.d.ts`.
+
+```typescript
+declare module "*.module.styl" {
+  const classes: { [key: string]: string };
+  export default classes;
+}
+```
+
 ### addPostcssPlugins([plugins])
 
 To add post-css plugins, you can use `addPostcssPlugins`.

src/customizers/webpack.js

@@ -239,6 +239,128 @@ export const addLessLoader = (loaderOptions = {}, customCssModules = {}) => conf
   return config;
 };
 
+export const addStylusLoader = (loaderOptions = {}, customCssModules = {}) => config => {
+  const MiniCssExtractPlugin = require("mini-css-extract-plugin");
+  const postcssNormalize = require("postcss-normalize");
+
+  const cssLoaderOptions = loaderOptions.cssLoaderOptions || {};
+  delete loaderOptions.cssLoaderOptions;
+
+  const { localIdentName } = loaderOptions;
+  let cssModules = loaderOptions.cssModules || { localIdentName };
+
+  if (!cssModules.localIdentName) {
+    cssModules = customCssModules;
+  }
+
+  cssModules.localIdentName = cssModules.localIdentName || "[local]--[hash:base64:5]";
+
+  const stylusRegex = /\.styl$/;
+  const stylusModuleRegex = /\.module\.styl$/;
+
+  const webpackEnv = process.env.NODE_ENV;
+  const isEnvDevelopment = webpackEnv === "development";
+  const isEnvProduction = webpackEnv === "production";
+  const shouldUseSourceMap = process.env.GENERATE_SOURCEMAP !== "false";
+  const publicPath = config.output.publicPath;
+  const shouldUseRelativeAssetPaths = publicPath === "./";
+
+  // copy from react-scripts
+  // https://github.com/facebook/create-react-app/blob/master/packages/react-scripts/config/webpack.config.js#L93
+  const getStyleLoaders = (cssOptions, preProcessor) => {
+    const loaders = [
+      isEnvDevelopment && require.resolve("style-loader"),
+      isEnvProduction && {
+        loader: MiniCssExtractPlugin.loader,
+        options: shouldUseRelativeAssetPaths ? { publicPath: "../../" } : {}
+      },
+      {
+        loader: require.resolve("css-loader"),
+        options: cssOptions
+      },
+      {
+        loader: require.resolve("postcss-loader"),
+        options: {
+          ident: "postcss",
+          plugins: () => [
+            require("postcss-flexbugs-fixes"),
+            require("postcss-preset-env")({
+              autoprefixer: {
+                flexbox: "no-2009"
+              },
+              stage: 3
+            }),
+            postcssNormalize()
+          ],
+          sourceMap: isEnvProduction && shouldUseSourceMap
+        }
+      }
+    ].filter(Boolean);
+    if (preProcessor) {
+      loaders.push(
+        {
+          loader: require.resolve("resolve-url-loader"),
+          options: {
+            sourceMap: isEnvProduction && shouldUseSourceMap
+          }
+        },
+        {
+          loader: require.resolve(preProcessor),
+          // not the same as react-scripts
+          options: Object.assign(
+            {
+              sourceMap: true
+            },
+            loaderOptions
+          )
+        }
+      );
+    }
+    return loaders;
+  };
+
+  const loaders = config.module.rules.find(rule => Array.isArray(rule.oneOf))
+    .oneOf;
+
+  // Insert stylus-loader as the penultimate item of loaders (before file-loader)
+  loaders.splice(
+    loaders.length - 1,
+    0,
+    {
+      test: stylusRegex,
+      exclude: stylusModuleRegex,
+      use: getStyleLoaders(
+        Object.assign(
+          {
+            importLoaders: 2,
+            sourceMap: isEnvProduction && shouldUseSourceMap
+          },
+          cssLoaderOptions
+        ),
+        "stylus-loader"
+      )
+    },
+    {
+      test: stylusModuleRegex,
+      use: getStyleLoaders(
+        Object.assign(
+          {
+            importLoaders: 2,
+            sourceMap: isEnvProduction && shouldUseSourceMap
+          },
+          cssLoaderOptions,
+          {
+            modules: cssModules
+          }
+        ),
+        "stylus-loader"
+      )
+    }
+  );
+
+  return config;
+};
+
 // to be used inside `overrideDevServer`, makes CRA watch all the folders
 // included `node_modules`, useful when you are working with linked packages
 // usage: `yarn start --watch-all`

src/customizers/webpack.test.js

@@ -177,6 +177,8 @@ test("adjustStyleLoaders find all style loaders and callback one by one", () =>
 
 test("addLessLoader", () => {});
 
+test("addStylusLoader", () => {});
+
 test("watchAll removes the watchOptions from config if --watch-all passed", () => {
   const watchOptions = { watch: true };
   const inputConfig = { watchOptions };