From 5e0308e106feec767b44a5fa29696009f95d3a2a Mon Sep 17 00:00:00 2001
From: Alexander Akait <4567934+alexander-akait@users.noreply.github.com>
Date: Thu, 25 May 2023 23:33:56 +0300
Subject: [PATCH] fix: handling error better (#515)

---
 src/index.js                                   | 10 +++++++++-
 src/utils.js                                   | 11 ++---------
 test/__snapshots__/implementation.test.js.snap | 13 ++++++++++---
 test/fixtures/implementation-error.js          |  1 +
 test/implementation.test.js                    | 11 +++++++++++
 5 files changed, 33 insertions(+), 13 deletions(-)
 create mode 100644 test/fixtures/implementation-error.js

diff --git a/src/index.js b/src/index.js
index 3ec5911..fa3c200 100644
--- a/src/index.js
+++ b/src/index.js
@@ -12,7 +12,15 @@ import LessError from "./LessError";
 async function lessLoader(source) {
   const options = this.getOptions(schema);
   const callback = this.async();
-  const implementation = getLessImplementation(this, options.implementation);
+  let implementation;
+
+  try {
+    implementation = getLessImplementation(this, options.implementation);
+  } catch (error) {
+    callback(error);
+
+    return;
+  }
 
   if (!implementation) {
     callback(
diff --git a/src/utils.js b/src/utils.js
index fe3a306..d742385 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -232,15 +232,8 @@ function getLessImplementation(loaderContext, implementation) {
   if (!implementation || typeof implementation === "string") {
     const lessImplPkg = implementation || "less";
 
-    try {
-      // eslint-disable-next-line import/no-dynamic-require, global-require
-      resolvedImplementation = require(lessImplPkg);
-    } catch (error) {
-      loaderContext.emitError(error);
-
-      // eslint-disable-next-line consistent-return
-      return;
-    }
+    // eslint-disable-next-line import/no-dynamic-require, global-require
+    resolvedImplementation = require(lessImplPkg);
   }
 
   // eslint-disable-next-line consistent-return
diff --git a/test/__snapshots__/implementation.test.js.snap b/test/__snapshots__/implementation.test.js.snap
index c7a7a4c..9214f35 100644
--- a/test/__snapshots__/implementation.test.js.snap
+++ b/test/__snapshots__/implementation.test.js.snap
@@ -3,14 +3,21 @@
 exports[`"implementation" option should throw error when unresolved package: errors 1`] = `
 [
   "ModuleBuildError: Module build failed (from \`replaced original path\`):
-Error: The Less implementation "unresolved" not found",
-  "ModuleError: Module Error (from \`replaced original path\`):
-(Emitted value instead of an instance of Error) Error: Cannot find module 'unresolved' from 'src/utils.js'",
+NonErrorEmittedError: (Emitted value instead of an instance of Error) Error: Cannot find module 'unresolved' from 'src/utils.js'",
+]
+`;
+
+exports[`"implementation" option should throw error when unresolved package: errors 2`] = `
+[
+  "ModuleBuildError: Module build failed (from \`replaced original path\`):
+Error: The Less implementation "/test/fixtures/implementation-error.js" not found",
 ]
 `;
 
 exports[`"implementation" option should throw error when unresolved package: warnings 1`] = `[]`;
 
+exports[`"implementation" option should throw error when unresolved package: warnings 2`] = `[]`;
+
 exports[`"implementation" option should work when implementation option is string: css 1`] = `
 ".box {
   color: #fe33ac;
diff --git a/test/fixtures/implementation-error.js b/test/fixtures/implementation-error.js
new file mode 100644
index 0000000..a5d3020
--- /dev/null
+++ b/test/fixtures/implementation-error.js
@@ -0,0 +1 @@
+module.exports = false;
diff --git a/test/implementation.test.js b/test/implementation.test.js
index b2a32ce..6206088 100644
--- a/test/implementation.test.js
+++ b/test/implementation.test.js
@@ -49,4 +49,15 @@ describe('"implementation" option', () => {
     expect(getWarnings(stats)).toMatchSnapshot("warnings");
     expect(getErrors(stats)).toMatchSnapshot("errors");
   });
+
+  it("should throw error when unresolved package", async () => {
+    const testId = "./basic.less";
+    const compiler = getCompiler(testId, {
+      implementation: require.resolve("./fixtures/implementation-error.js"),
+    });
+    const stats = await compile(compiler);
+
+    expect(getWarnings(stats)).toMatchSnapshot("warnings");
+    expect(getErrors(stats)).toMatchSnapshot("errors");
+  });
 });