feat(validation): clarify username format and uniqueness error messages

app/Http/Controllers/AuthController.php

@@ -168,7 +168,7 @@ public function completeOnboarding(Request $request)
             'appreciations.*' => ['integer', 'distinct', 'exists:users,id'],
         ], [
             'school.required' => 'Please enter your school, college, or institution name.',
-            'username.regex' => 'Username can only contain letters, numbers, and underscores.',
+            'username.regex' => "Username can only contain letters, numbers, and underscores. Dots aren't allowed.",
             'username.unique' => 'This username is already taken. Please choose another one.',
             'image.image' => 'The uploaded file must be an image (PNG, JPG, JPEG, WEBP).',
             'image.max' => 'The profile image may not be greater than 5MB.',

app/Http/Requests/Profile/UpdateProfileRequest.php

@@ -46,4 +46,17 @@ public function rules(): array
             'receive_emails' => ['sometimes', 'boolean'],
         ];
     }
+
+    /**
+     * Get custom messages for validator errors.
+     *
+     * @return array<string, string>
+     */
+    public function messages(): array
+    {
+        return [
+            'username.regex' => "Username can only contain letters, numbers, and underscores. Dots aren't allowed.",
+            'username.unique' => 'This username is already taken. Please choose another one.',
+        ];
+    }
 }

app/Http/Requests/User/StoreUserRequest.php

@@ -48,4 +48,17 @@ protected function passedValidation(): void
             'email_verified_at' => now(),
         ]);
     }
+
+    /**
+     * Get custom messages for validator errors.
+     *
+     * @return array<string, string>
+     */
+    public function messages(): array
+    {
+        return [
+            'username.regex' => "Username can only contain letters, numbers, and underscores. Dots aren't allowed.",
+            'username.unique' => 'This username is already taken. Please choose another one.',
+        ];
+    }
 }

app/Http/Requests/User/UpdateUserRequest.php

@@ -53,4 +53,17 @@ public function rules(): array
 
         return $rules;
     }
+
+    /**
+     * Get custom messages for validator errors.
+     *
+     * @return array<string, string>
+     */
+    public function messages(): array
+    {
+        return [
+            'username.regex' => "Username can only contain letters, numbers, and underscores. Dots aren't allowed.",
+            'username.unique' => 'This username is already taken. Please choose another one.',
+        ];
+    }
 }

tests/Feature/ProfileUsernameTest.php

@@ -57,3 +57,37 @@
     expect($user->fresh()->name)->toBe('Updated Name');
     expect($user->fresh()->username)->toBe('my_handle');
 });
+
+test('username update shows clear validation message when format is invalid (e.g. dots)', function () {
+    $user = User::factory()->create([
+        'username' => 'valid_user',
+    ]);
+
+    $response = $this->actingAs($user)->put('/profile', [
+        'name' => $user->name,
+        'username' => 'invalid.user',
+    ]);
+
+    $response->assertSessionHasErrors([
+        'username' => "Username can only contain letters, numbers, and underscores. Dots aren't allowed.",
+    ]);
+});
+
+test('username update shows clear validation message when username is already taken', function () {
+    User::factory()->create([
+        'username' => 'taken_user',
+    ]);
+
+    $user = User::factory()->create([
+        'username' => 'valid_user',
+    ]);
+
+    $response = $this->actingAs($user)->put('/profile', [
+        'name' => $user->name,
+        'username' => 'taken_user',
+    ]);
+
+    $response->assertSessionHasErrors([
+        'username' => 'This username is already taken. Please choose another one.',
+    ]);
+});