fix: import alias without tilde (#335)

package.json

@@ -75,6 +75,7 @@
     "npm-run-all": "^4.1.5",
     "prettier": "^2.0.4",
     "standard-version": "^7.0.1",
+    "strip-ansi": "^6.0.0",
     "webpack": "^4.42.1"
   },
   "keywords": [

src/createWebpackLessPlugin.js

@@ -31,7 +31,7 @@ function createWebpackLessPlugin(loaderContext) {
   const resolve = loaderContext.getResolve({
     mainFields: ['less', 'style', 'main', '...'],
     mainFiles: ['_index', 'index', '...'],
-    extensions: ['.less', '.css', '...'],
+    extensions: ['.less', '.css'],
   });
 
   class WebpackFileManager extends less.FileManager {
@@ -61,7 +61,27 @@ function createWebpackLessPlugin(loaderContext) {
       return filename;
     }
 
-    async loadFile(filename, currentDirectory, options) {
+    resolveRequests(context, possibleRequests) {
+      if (possibleRequests.length === 0) {
+        return Promise.reject();
+      }
+
+      return resolve(context, possibleRequests[0])
+        .then((result) => {
+          return result;
+        })
+        .catch((error) => {
+          const [, ...tailPossibleRequests] = possibleRequests;
+
+          if (tailPossibleRequests.length === 0) {
+            throw error;
+          }
+
+          return this.resolveRequests(context, tailPossibleRequests);
+        });
+    }
+
+    async loadFile(filename, currentDirectory, options, ...args) {
       const url = this.getUrl(filename, options);
 
       const moduleRequest = urlToRequest(
@@ -71,7 +91,18 @@ function createWebpackLessPlugin(loaderContext) {
 
       // Less is giving us trailing slashes, but the context should have no trailing slash
       const context = currentDirectory.replace(trailingSlash, '');
-      const resolvedFilename = await resolve(context, moduleRequest);
+      let resolvedFilename;
+
+      try {
+        resolvedFilename = await this.resolveRequests(context, [
+          moduleRequest,
+          url,
+        ]);
+      } catch (error) {
+        loaderContext.emitError(error);
+
+        return super.loadFile(filename, currentDirectory, options, ...args);
+      }
 
       loaderContext.addDependency(resolvedFilename);
 

test/__snapshots__/index.test.js.snap

@@ -11,14 +11,18 @@ exports[`should fail if a file is tried to be loaded from include paths and with
       in /test/fixtures/less/error-mixed-resolvers.less (line 3, column 0)"
 `;
 
-exports[`should provide a useful error message if the import could not be found 1`] = `
-"Module build failed (from ./src/cjs.js):
+exports[`should provide a useful error message if the import could not be found: errors 1`] = `
+Array [
+  "ModuleBuildError: Module build failed (from \`replaced original path\`):
 
 
 @import \\"not-existing\\";
 ^
-Can't resolve './not-existing.less' in '/test/fixtures/less'
-      in /test/fixtures/less/error-import-not-existing.less (line 1, column 0)"
+'not-existing' wasn't found. Tried - /test/fixtures/less/not-existing.less,npm://not-existing,npm://not-existing.less,not-existing.less
+      in /test/fixtures/less/error-import-not-existing.less (line 1, column 0)",
+  "ModuleError: Module Error (from \`replaced original path\`):
+Can't resolve 'not-existing.less' in '/test/fixtures/less'",
+]
 `;
 
 exports[`should provide a useful error message if there was a syntax error 1`] = `

test/fixtures/less/import-webpack-aliases.less

@@ -0,0 +1,11 @@
+@import "~fileAlias";
+@import "~assets/folder/url-path.less";
+@import "assets/folder/url-path.less";
+
+body {
+  background: url(assets/resources/circle.svg);
+}
+
+.abs {
+  background: url(~assets/resources/circle.svg);
+}

test/helpers/createSpec.js

@@ -21,6 +21,8 @@ const ignore = [
 ];
 const lessReplacements = [
   [/~some\//g, '../node_modules/some/'],
+  [/(~)?assets\//g, '../less/'],
+  [/~fileAlias/g, '../less/img.less'],
   [/~(aliased-)?some"/g, '../node_modules/some/module.less"'],
 ];
 const cssReplacements = [[/\.\.\/node_modules\/some\//g, '~some/']];

test/helpers/getErrors.js

@@ -0,0 +1,5 @@
+import normalizeErrors from './normalizeErrors';
+
+export default (stats) => {
+  return normalizeErrors(stats.compilation.errors).sort();
+};

test/helpers/normalizeErrors.js

@@ -0,0 +1,24 @@
+// eslint-disable-next-line import/no-extraneous-dependencies
+import stripAnsi from 'strip-ansi';
+
+function removeCWD(str) {
+  const isWin = process.platform === 'win32';
+  let cwd = process.cwd();
+
+  if (isWin) {
+    // eslint-disable-next-line no-param-reassign
+    str = str.replace(/\\/g, '/');
+    // eslint-disable-next-line no-param-reassign
+    cwd = cwd.replace(/\\/g, '/');
+  }
+
+  return stripAnsi(str)
+    .replace(/\(from .*?\)/, '(from `replaced original path`)')
+    .replace(new RegExp(cwd, 'g'), '');
+}
+
+export default (errors) => {
+  return errors.map((error) =>
+    removeCWD(error.toString().split('\n').slice(0, 12).join('\n'))
+  );
+};

test/index.test.js

@@ -4,6 +4,7 @@ import compile from './helpers/compile';
 import moduleRules from './helpers/moduleRules';
 import { readCssFixture, readSourceMap } from './helpers/readFixture';
 import compareErrorMessage from './helpers/compareErrorMessage';
+import getErrors from './helpers/getErrors';
 
 const nodeModulesPath = path.resolve(__dirname, 'fixtures', 'node_modules');
 
@@ -88,10 +89,12 @@ test('should add all resolved imports as dependencies, including node_modules',
   );
 });
 
-test('should resolve aliases as configured', async () => {
+test('should resolve aliases in diffrent variants', async () => {
   await compileAndCompare('import-webpack-alias', {
     resolveAlias: {
       'aliased-some': 'some',
+      fileAlias: path.resolve(__dirname, 'fixtures', 'less', 'img.less'),
+      assets: path.resolve(__dirname, 'fixtures', 'less'),
     },
   });
 });
@@ -300,9 +303,7 @@ test('should provide a useful error message if the import could not be found', a
     moduleRules.basic()
   ).catch((e) => e);
 
-  expect(err).toBeInstanceOf(Error);
-
-  compareErrorMessage(err.message);
+  expect(getErrors(err.stats)).toMatchSnapshot('errors');
 });
 
 test('should provide a useful error message if there was a syntax error', async () => {