Enhance validateMethod to Include File Paths in Duplicate Command Errors

lib/api/_loaders/_command-loader.js

@@ -16,6 +16,8 @@
     this.ignoreUnderscoreLeadingNames = true;
   }
 
+  static commandRegistry = new Map();
+
   static isTypeImplemented(instance, method, type) {
     const methodTypes = method.split('|');
 
@@ -50,15 +52,26 @@
       this.nightwatchInstance.overridableCommands.add(this.commandName);
     }
 
-    if (this.nightwatchInstance.isApiMethodDefined(this.commandName, namespace) && !this.nightwatchInstance.overridableCommands.has(this.commandName)) {
-      const err = new TypeError(`Error while loading the API commands: the ${this.type} ${this.namespace || ''}.${this.commandName}() is already defined.`);
+    const commandKey = `${this.namespace || ''}.${this.commandName}`;
+    const currentFile = this.fileName;
+
+    if (BaseCommandLoader.commandRegistry.has(commandKey)) {
+      const firstDefinedFile = BaseCommandLoader.commandRegistry.get(commandKey);
+
+      const err = new TypeError(
+        `Error while loading the API commands: the ${this.type} ${commandKey}() is already defined.\n` +
+        `- First defined in: ${firstDefinedFile}\n` +
+        `- Current file: ${currentFile}`
+      );
+
       err.displayed = false;
-      err.detailedErr = `Source: ${this.fileName}`;
       err.showTrace = false;
 
       throw err;
     }
 
+    BaseCommandLoader.commandRegistry.set(commandKey, currentFile);
+
     return this;
   }
 

test/src/api/commands/testDuplicateCommandError.js

@@ -0,0 +1,49 @@
+const assert = require('assert');
+const BaseCommandLoader = require('../../../../lib/api/_loaders/_command-loader.js');
+
+describe('BaseCommandLoader - Duplicate Command Error', function () {
+  it('should throw an error with file paths when duplicate commands are defined', function () {
+    // Create two instances of the command loader to simulate commands from two different files
+    const loader1 = new BaseCommandLoader({});
+    loader1.fileName = '/path/to/firstFile.js';
+    loader1.commandName = 'testCommand';
+    loader1.namespace = 'testNamespace';
+
+    const loader2 = new BaseCommandLoader({});
+    loader2.fileName = '/path/to/secondFile.js';
+    loader2.commandName = 'testCommand';
+    loader2.namespace = 'testNamespace';
+
+    // Validate the first command, it should register without issues
+    loader1.validateMethod(null);
+
+    // The second command should throw a detailed error
+    assert.throws(
+      () => loader2.validateMethod(null),
+      (err) => {
+        assert.ok(err instanceof TypeError);
+        assert.ok(err.message.includes('testNamespace.testCommand'));
+        assert.ok(err.message.includes('/path/to/firstFile.js'));
+        assert.ok(err.message.includes('/path/to/secondFile.js'));
+
+        return true;
+      }
+    );
+  });
+
+  it('should not throw an error for commands in different namespaces', function () {
+    const loader1 = new BaseCommandLoader({});
+    loader1.fileName = '/path/to/firstFile.js';
+    loader1.commandName = 'testCommand';
+    loader1.namespace = 'namespace1';
+
+    const loader2 = new BaseCommandLoader({});
+    loader2.fileName = '/path/to/secondFile.js';
+    loader2.commandName = 'testCommand';
+    loader2.namespace = 'namespace2';
+
+    // Both commands should register without issues
+    assert.doesNotThrow(() => loader1.validateMethod(null));
+    assert.doesNotThrow(() => loader2.validateMethod(null));
+  });
+});