Add new option dropEmptyFile

Closes #21

Author: c0gnize

README.md

@@ -13,18 +13,22 @@ yarn add -D dts-css-modules-loader
 {
   test: /\.scss$/,
   use: [
-    'style-loader',
+    {
+      loader: 'style-loader',
+      options: {
+        esModule: false,
+      },
+    },
     {
       loader: 'dts-css-modules-loader',
       options: {
-        namedExport: true,
-        banner: "// This file is generated automatically"
+        namedExport: true
       }
     },
     {
       loader: 'css-loader',
       options: {
-        // options for the v4 of css-loader
+        // options for the v5 of css-loader
         modules: {
           exportLocalsConvention: 'camelCaseOnly',
           localIdentName: '[local]'
@@ -72,7 +76,10 @@ customTypings: classes => {
   return content;
 }
 ```
-`namedExport` option will be ignored
+`namedExport` and `banner` option will be ignored
+
+### `dropEmptyFile`
+If there are no classes, the typings file will not be generated, and the existing will be deleted.
 
 ## Usage in Typescript
 ```ts

index.js

@@ -4,21 +4,30 @@ const fp = require('path');
 const loaderUtils = require('loader-utils');
 
 /** @type {import('webpack').loader.Loader} */
-module.exports = function(content) {
+module.exports = function (content) {
   this.cacheable && this.cacheable();
 
-  /** @type {{ banner?: string, namedExport?: boolean, customTypings?: (classes: string[]) => string }} */
+  /**
+   * @type {{
+   *   banner?: string,
+   *   namedExport?: boolean,
+   *   customTypings?: (classes: string[]) => string,
+   *   dropEmptyFile?: boolean
+   * }}
+   */
   const options = loaderUtils.getOptions(this) || {};
   const callback = this.async();
 
-  let typings = '';
+  const classes = getClasses(content);
+  const dtsPath = getDtsPath(this.resourcePath);
 
-  if (options.banner) {
-    typings = `${options.banner}\n`;
-  }
+  if (options.dropEmptyFile && classes.length === 0) {
+    if (fs.existsSync(dtsPath)) {
+      fs.rmSync(dtsPath);
+    }
+  } else {
+    let typings = options.banner ? `${options.banner}\n` : '';
 
-  {
-    const classes = getClasses(content);
     if (options.customTypings) {
       typings = options.customTypings(classes);
     } else if (options.namedExport) {
@@ -33,9 +42,9 @@ module.exports = function(content) {
       }
       typings += `}\ndeclare const styles: ${i};\nexport = styles;\n`;
     }
-  }
 
-  fs.writeFileSync(getDtsPath(this.resourcePath), typings);
+    fs.writeFileSync(dtsPath, typings);
+  }
 
   callback(null, content);
 };
@@ -74,7 +83,7 @@ function getClasses(content) {
     /** @type {RegExpExecArray} */
     let match;
     const regex = isCssLoader4NamedExport ? classesOfNamedExportRegex : classesRegex;
-    while (match = regex.exec(content)) {
+    while ((match = regex.exec(content))) {
       if (classes.indexOf(match[1]) === -1) {
         classes.push(match[1]);
       }
@@ -98,7 +107,8 @@ function getDtsPath(path) {
  * @param {string} [path]
  */
 function getInterfaceName(path) {
-  return fp.basename(path)
+  return fp
+    .basename(path)
     .replace(/^(\w)/, (_, c) => 'I' + c.toUpperCase())
     .replace(/\W+(\w)/g, (_, c) => c.toUpperCase());
 }

package.json

@@ -1,6 +1,6 @@
 {
   "name": "dts-css-modules-loader",
-  "version": "1.1.1",
+  "version": "1.2.1",
   "description": "webpack loader to generate typings for css modules",
   "dependencies": {
     "loader-utils": "^2.0.0"
@@ -16,5 +16,8 @@
     "loader"
   ],
   "license": "MIT",
-  "homepage": "https://github.com/Megaputer/dts-css-modules-loader"
+  "homepage": "https://github.com/Megaputer/dts-css-modules-loader",
+  "devDependencies": {
+    "@types/webpack": "^4.41.26"
+  }
 }

yarn.lock

@@ -2,6 +2,54 @@
 # yarn lockfile v1
 
 
+"@types/anymatch@*":
+  version "1.3.1"
+  resolved "https://registry.yarnpkg.com/@types/anymatch/-/anymatch-1.3.1.tgz#336badc1beecb9dacc38bea2cf32adf627a8421a"
+  integrity sha512-/+CRPXpBDpo2RK9C68N3b2cOvO0Cf5B9aPijHsoDQTHivnGSObdOF2BRQOYjojWTDy6nQvMjmqRXIxH55VjxxA==
+
+"@types/node@*":
+  version "14.14.35"
+  resolved "https://registry.yarnpkg.com/@types/node/-/node-14.14.35.tgz#42c953a4e2b18ab931f72477e7012172f4ffa313"
+  integrity sha512-Lt+wj8NVPx0zUmUwumiVXapmaLUcAk3yPuHCFVXras9k5VT9TdhJqKqGVUQCD60OTMCl0qxJ57OiTL0Mic3Iag==
+
+"@types/source-list-map@*":
+  version "0.1.2"
+  resolved "https://registry.yarnpkg.com/@types/source-list-map/-/source-list-map-0.1.2.tgz#0078836063ffaf17412349bba364087e0ac02ec9"
+  integrity sha512-K5K+yml8LTo9bWJI/rECfIPrGgxdpeNbj+d53lwN4QjW1MCwlkhUms+gtdzigTeUyBr09+u8BwOIY3MXvHdcsA==
+
+"@types/tapable@*":
+  version "1.0.6"
+  resolved "https://registry.yarnpkg.com/@types/tapable/-/tapable-1.0.6.tgz#a9ca4b70a18b270ccb2bc0aaafefd1d486b7ea74"
+  integrity sha512-W+bw9ds02rAQaMvaLYxAbJ6cvguW/iJXNT6lTssS1ps6QdrMKttqEAMEG/b5CR8TZl3/L7/lH0ZV5nNR1LXikA==
+
+"@types/uglify-js@*":
+  version "3.13.0"
+  resolved "https://registry.yarnpkg.com/@types/uglify-js/-/uglify-js-3.13.0.tgz#1cad8df1fb0b143c5aba08de5712ea9d1ff71124"
+  integrity sha512-EGkrJD5Uy+Pg0NUR8uA4bJ5WMfljyad0G+784vLCNUkD+QwOJXUbBYExXfVGf7YtyzdQp3L/XMYcliB987kL5Q==
+  dependencies:
+    source-map "^0.6.1"
+
+"@types/webpack-sources@*":
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/@types/webpack-sources/-/webpack-sources-2.1.0.tgz#8882b0bd62d1e0ce62f183d0d01b72e6e82e8c10"
+  integrity sha512-LXn/oYIpBeucgP1EIJbKQ2/4ZmpvRl+dlrFdX7+94SKRUV3Evy3FsfMZY318vGhkWUS5MPhtOM3w1/hCOAOXcg==
+  dependencies:
+    "@types/node" "*"
+    "@types/source-list-map" "*"
+    source-map "^0.7.3"
+
+"@types/webpack@^4.41.26":
+  version "4.41.26"
+  resolved "https://registry.yarnpkg.com/@types/webpack/-/webpack-4.41.26.tgz#27a30d7d531e16489f9c7607c747be6bc1a459ef"
+  integrity sha512-7ZyTfxjCRwexh+EJFwRUM+CDB2XvgHl4vfuqf1ZKrgGvcS5BrNvPQqJh3tsZ0P6h6Aa1qClVHaJZszLPzpqHeA==
+  dependencies:
+    "@types/anymatch" "*"
+    "@types/node" "*"
+    "@types/tapable" "*"
+    "@types/uglify-js" "*"
+    "@types/webpack-sources" "*"
+    source-map "^0.6.0"
+
 big.js@^5.2.2:
   version "5.2.2"
   resolved "https://registry.yarnpkg.com/big.js/-/big.js-5.2.2.tgz#65f0af382f578bcdc742bd9c281e9cb2d7768328"
@@ -32,3 +80,13 @@ minimist@^1.2.5:
   version "1.2.5"
   resolved "https://registry.yarnpkg.com/minimist/-/minimist-1.2.5.tgz#67d66014b66a6a8aaa0c083c5fd58df4e4e97602"
   integrity sha512-FM9nNUYrRBAELZQT3xeZQ7fmMOBg6nWNmJKTcgsJeaLstP/UODVpGsr5OhXhhXg6f+qtJ8uiZ+PUxkDWcgIXLw==
+
+source-map@^0.6.0, source-map@^0.6.1:
+  version "0.6.1"
+  resolved "https://registry.yarnpkg.com/source-map/-/source-map-0.6.1.tgz#74722af32e9614e9c287a8d0bbde48b5e2f1a263"
+  integrity sha512-UjgapumWlbMhkBgzT7Ykc5YXUT46F0iKu8SGXq0bcwP5dz/h0Plj6enJqjz1Zbq2l5WaqYnrVbwWOWMyF3F47g==
+
+source-map@^0.7.3:
+  version "0.7.3"
+  resolved "https://registry.yarnpkg.com/source-map/-/source-map-0.7.3.tgz#5302f8169031735226544092e64981f751750383"
+  integrity sha512-CkCj6giN3S+n9qrYiBTX5gystlENnRW5jZeNLHpe6aue+SrHcG5VYwujhW9s4dY31mEGsxBDrHR6oI69fTXsaQ==