Updates the class name generation logic to be independent of css-loader library

This change is necessary because the latest release, [email protected],
closes the opportunity to access its default class name generation
function. Thus, the necessary code is copy/pasted directly into this
library. It should introduce no changes in the actual class name
generation algo.

Author: birdofpreyru

package-lock.json

@@ -5,7 +5,8 @@
     "@dr.pogodin/postcss-modules-parser": "^1.2.2",
     "ajv": "^6.12.6",
     "ajv-keywords": "^3.2.0",
-    "css-loader": "^4.3.0",
+    "cssesc": "^3.0.0",
+    "loader-utils": "^2.0.0",
     "postcss": "^8.1.1",
     "postcss-modules": "^3.2.2",
     "postcss-modules-extract-imports": "^3.0.0",

package.json

@@ -0,0 +1,50 @@
+/**
+ * getLocalIdent() function taken from [email protected].
+ */
+
+import path from 'path';
+import cssesc from 'cssesc';
+import {
+  interpolateName,
+} from 'loader-utils';
+
+// eslint-disable-next-line no-control-regex
+const filenameReservedRegex = /["*/:<>?\\|]/g;
+// eslint-disable-next-line no-control-regex
+const reControlChars = /[\u0000-\u001f\u0080-\u009f]/g;
+
+const normalizePath = (file) => {
+  return path.sep === '\\' ? file.replace(/\\/g, '/') : file;
+};
+
+const escapeLocalIdent = (localident) => {
+  return cssesc(
+    localident
+
+      // For `[hash]` placeholder
+      .replace(/^((-?\d)|--)/, '_$1')
+      .replace(filenameReservedRegex, '-')
+      .replace(reControlChars, '-')
+      .replace(/\./g, '-'),
+    {isIdentifier: true},
+  );
+};
+
+export default function getLocalIdent (
+  loaderContext,
+  localIdentName,
+  localName,
+  options,
+) {
+  const {context, hashPrefix} = options;
+  const {resourcePath} = loaderContext;
+  const request = normalizePath(path.relative(context, resourcePath));
+
+  // eslint-disable-next-line no-param-reassign
+  options.content = `${hashPrefix + request}\u0000${localName}`;
+
+  const ident = interpolateName(loaderContext, localIdentName, options)
+    .replace(/\[local]/gi, localName);
+
+  return escapeLocalIdent(ident);
+}

src/getLocalIdent.js

@@ -8,14 +8,12 @@ import {
   resolve,
 } from 'path';
 import Parser from '@dr.pogodin/postcss-modules-parser';
-import {
-  getModulesOptions,
-} from 'css-loader/dist/utils';
 import postcss from 'postcss';
 import ExtractImports from 'postcss-modules-extract-imports';
 import LocalByDefault from 'postcss-modules-local-by-default';
 import newScopePlugin from 'postcss-modules-scope';
 import Values from 'postcss-modules-values';
+import getLocalIdent from './getLocalIdent';
 import optionsDefaults from './schemas/optionsDefaults';
 import type {
   GenerateScopedNameConfigurationType,
@@ -46,12 +44,6 @@ type OptionsType = {|
   context?: string,
 |};
 
-// As of now CSS loader does not export its default getLocalIdent(..) function,
-// which we need to generate the classnames. However, this goofy way to get it
-// works fine. If one day internal changes in css-loader break this workaround,
-// it will be necessary just to commit them a patch which exports the function.
-const {getLocalIdent} = getModulesOptions({modules: true}, {});
-
 const getFiletypeOptions = (cssSourceFilePath: string, filetypes: FiletypesConfigurationType): ?FiletypeOptionsType => {
   const extension = cssSourceFilePath.slice(cssSourceFilePath.lastIndexOf('.'));
   const filetype = filetypes ? filetypes[extension] : null;