Fixed CLI --config failures hiding the real cause behind a generic Cannot open config file message (#1435)

CHANGELOG.md

@@ -2,6 +2,7 @@ Change Log
 
 v5.4.7
 ---
+* Fixed CLI `--config` failures hiding the real cause behind a generic `Cannot open config file` message. Fixes https://github.com/javascript-obfuscator/javascript-obfuscator/issues/1101
 * Fixed `sourceMapFileName` ending in `.js.map` (e.g. `foo.min.js.map`) being mangled in the emitted `//# sourceMappingURL=` comment. Fixes https://github.com/javascript-obfuscator/javascript-obfuscator/issues/1312
 * Fixed `URIError: URI malformed` crash when `stringArray` with `base64`/`rc4` encoding processed a string literal containing lone surrogate code units (e.g. `"[^\uD800-\uDFFF]"`). Fixes https://github.com/javascript-obfuscator/javascript-obfuscator/issues/1431
 * Bumped the production `brace-expansion` transitive dependency to a patched version, resolving `CVE-2026-25547`. Fixes https://github.com/javascript-obfuscator/javascript-obfuscator/issues/1405

src/cli/utils/CLIUtils.ts

@@ -15,26 +15,32 @@ export class CLIUtils {
      * @returns {TDictionary}
      */
     public static getUserConfig(configPath: string): TDictionary {
-        let config: TDictionary;
-
         const configFileExtension: string = path.extname(configPath);
         const isValidExtension: boolean = CLIUtils.allowedConfigFileExtensions.includes(configFileExtension);
 
         if (!isValidExtension) {
-            throw new ReferenceError('Given config path must be a valid `.js|.mjs|.cjs` or `.json` file path');
+            throw new ReferenceError('Given config path must be a valid `.js`, `.cjs` or `.json` file path');
+        }
+
+        const errors: Error[] = [];
+
+        try {
+            return require(configPath);
+        } catch (error) {
+            errors.push(<Error>error);
         }
 
         try {
-            config = require(configPath);
-        } catch {
-            try {
-                config = __non_webpack_require__(configPath);
-            } catch {
-                throw new ReferenceError(`Cannot open config file with path: ${configPath}`);
-            }
+            return __non_webpack_require__(configPath);
+        } catch (error) {
+            errors.push(<Error>error);
         }
 
-        return config;
+        // surface the underlying reason (invalid JSON, `ERR_REQUIRE_ESM`, missing file, ...)
+        // instead of masking it behind a generic message
+        throw new ReferenceError(
+            `Cannot open config file with path: ${configPath}. Reason: ${CLIUtils.getConfigErrorReason(errors)}`
+        );
     }
 
     /**
@@ -44,4 +50,20 @@ export class CLIUtils {
     public static stringifyOptionAvailableValues(optionEnum: TDictionary): string {
         return Object.values(optionEnum).join(`${StringSeparator.Comma} `);
     }
+
+    /**
+     * @param {Error[]} errors
+     * @returns {string}
+     */
+    private static getConfigErrorReason(errors: Error[]): string {
+        const [firstError, secondError] = errors;
+
+        // in the webpack bundle the real reason comes from the `__non_webpack_require__` call (the second error);
+        // in a plain Node/ts-node context `__non_webpack_require__` is not defined, so the real reason is the first error
+        if (secondError && !secondError.message.includes('__non_webpack_require__')) {
+            return secondError.message;
+        }
+
+        return firstError.message;
+    }
 }

test/fixtures/invalid-config.json

@@ -0,0 +1,5 @@
+{
+    compact: true,
+    selfDefending: false,
+    sourceMap: true
+}

test/unit-tests/cli/utils/CLIUtils.spec.ts

@@ -106,6 +106,27 @@ describe('CLIUtils', () => {
                 assert.throws(testFunc, /Cannot open config file/);
             });
         });
+
+        // https://github.com/javascript-obfuscator/javascript-obfuscator/issues/1101
+        describe('Variant #4: config file with invalid content', () => {
+            const configDirName: string = 'test/fixtures';
+            const configFileName: string = 'invalid-config.json';
+            const configFilePath: string = `../../../${configDirName}/${configFileName}`;
+
+            let testFunc: () => void;
+
+            before(() => {
+                testFunc = () => CLIUtils.getUserConfig(configFilePath);
+            });
+
+            it('should throw an error that includes the config file path', () => {
+                assert.throws(testFunc, /Cannot open config file with path/);
+            });
+
+            it('should surface the underlying reason instead of masking it', () => {
+                assert.throws(testFunc, /Reason:.*JSON/);
+            });
+        });
     });
 
     describe('stringifyOptionAvailableValues', () => {