test: fiber option

README.md

@@ -172,7 +172,7 @@ module.exports = {
 Note that when using `sass` (`Dart Sass`), **synchronous compilation is twice as fast as asynchronous compilation** by default, due to the overhead of asynchronous callbacks.
 To avoid this overhead, you can use the [fibers](https://www.npmjs.com/package/fibers) package to call asynchronous importers from the synchronous code path.
 
-To enable this, pass the `Fiber` class to the `fiber` option:
+To enable this, pass the `Fiber` class to the `sassOptions.fiber` option:
 
 **webpack.config.js**
 
@@ -189,7 +189,9 @@ module.exports = {
             loader: 'sass-loader',
             options: {
               implementation: require('sass'),
-              fiber: require('fibers'),
+              sassOptions: {
+                fiber: require('fibers'),
+              },
             },
           },
         ],

package.json

@@ -63,6 +63,7 @@
     "eslint": "^6.2.1",
     "eslint-config-prettier": "^6.1.0",
     "eslint-plugin-import": "^2.18.2",
+    "fibers": "^4.0.1",
     "file-loader": "^4.2.0",
     "husky": "^3.0.4",
     "jest": "^24.9.0",

test/__snapshots__/sassOptions-option.test.js.snap

@@ -32,6 +32,22 @@ exports[`sassOptions option should work when the option like "Object" (node-sass
 
 exports[`sassOptions option should work when the option like "Object" (node-sass) (scss): warnings 1`] = `Array []`;
 
+exports[`sassOptions option should work with the "fibers" option (dart-sass) (sass): errors 1`] = `Array []`;
+
+exports[`sassOptions option should work with the "fibers" option (dart-sass) (sass): warnings 1`] = `Array []`;
+
+exports[`sassOptions option should work with the "fibers" option (dart-sass) (scss): errors 1`] = `Array []`;
+
+exports[`sassOptions option should work with the "fibers" option (dart-sass) (scss): warnings 1`] = `Array []`;
+
+exports[`sassOptions option should work with the "fibers" option (node-sass) (sass): errors 1`] = `Array []`;
+
+exports[`sassOptions option should work with the "fibers" option (node-sass) (sass): warnings 1`] = `Array []`;
+
+exports[`sassOptions option should work with the "fibers" option (node-sass) (scss): errors 1`] = `Array []`;
+
+exports[`sassOptions option should work with the "fibers" option (node-sass) (scss): warnings 1`] = `Array []`;
+
 exports[`sassOptions option should work with the "functions" option (dart-sass) (sass): errors 1`] = `Array []`;
 
 exports[`sassOptions option should work with the "functions" option (dart-sass) (sass): warnings 1`] = `Array []`;

test/sassOptions-option.test.js

@@ -3,6 +3,7 @@
  */
 import path from 'path';
 
+import semver from 'semver';
 import nodeSass from 'node-sass';
 import dartSass from 'sass';
 
@@ -119,6 +120,27 @@ describe('sassOptions option', () => {
         expect(stats.compilation.warnings).toMatchSnapshot('warnings');
         expect(stats.compilation.errors).toMatchSnapshot('errors');
       });
+
+      if (semver.satisfies(process.version, '>= 10')) {
+        it(`should work with the "fibers" option (${implementationName}) (${syntax})`, async () => {
+          const testId = getTestId('language', syntax);
+          const options = {
+            implementation: getImplementationByName(implementationName),
+            sassOptions: {
+              // eslint-disable-next-line global-require
+              fibers: require('fibers'),
+            },
+          };
+          const stats = await compile(testId, { loader: { options } });
+
+          expect(getCodeFromBundle(stats).css).toBe(
+            getCodeFromSass(testId, options).css
+          );
+
+          expect(stats.compilation.warnings).toMatchSnapshot('warnings');
+          expect(stats.compilation.errors).toMatchSnapshot('errors');
+        });
+      }
     });
   });
 });

test/validate-options.test.js

@@ -36,6 +36,12 @@ it('validate options', () => {
   ).not.toThrow();
   expect(() => validate({ sassOptions: () => {} })).not.toThrow();
   expect(() => validate({ sassOptions: true })).toThrowErrorMatchingSnapshot();
+  expect(() =>
+    validate({ sassOptions: { fiber: { mock: true } } })
+  ).not.toThrow();
+  expect(() =>
+    validate({ sassOptions: { indentWidth: 6, linefeed: 'crlf' } })
+  ).not.toThrow();
 
   expect(() => validate({ prependData: '$color: red;' })).not.toThrow();
   expect(() => validate({ prependData: () => '$color: red;' })).not.toThrow();