Add non-ASCII character check for username suggestions

.github/workflows/add-remove-label-on-comment.yml

@@ -17,4 +17,3 @@ on:
 jobs:
   add_remove_labels:
     uses: openedx/.github/.github/workflows/add-remove-label-on-comment.yml@master
-

.github/workflows/check_python_dependencies.yml

@@ -14,18 +14,18 @@ jobs:
     steps:
       - name: Checkout Repository
         uses: actions/checkout@v4
-                    
+
       - name: Set up Python
         uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python-version }}
-      
+
       - name: Install repo-tools
         run: pip install edx-repo-tools[find_dependencies]
 
       - name: Install setuptool
-        run: pip install setuptools  
-      
+        run: pip install setuptools
+
       - name: Run Python script
         run: |
           find_python_dependencies \
@@ -37,4 +37,3 @@ jobs:
             --ignore https://github.com/mitodl/edx-sga \
             --ignore https://github.com/edx/token-utils \
             --ignore https://github.com/open-craft/xblock-poll
-

lms/djangoapps/course_api/views.py

@@ -172,7 +172,7 @@ class LazyPageNumberPagination(NamespacedPageNumberPagination):
 
     The paginator cache uses ``@cached_property`` to cache the property values for
     count and num_pages.  It assumes these won't change, but in the case of a
-    LazySquence, its count gets updated as we move through it.  This class clears
+    LazySequence, its count gets updated as we move through it.  This class clears
     the cached property values before reporting results so they will be recalculated.
 
     """

openedx/core/djangoapps/user_authn/tests/test_utils.py

@@ -9,7 +9,11 @@
 from django.test.utils import override_settings
 
 from openedx.core.djangoapps.oauth_dispatch.tests.factories import ApplicationFactory
-from openedx.core.djangoapps.user_authn.utils import is_safe_login_or_logout_redirect
+from openedx.core.djangoapps.user_authn.utils import (
+    is_safe_login_or_logout_redirect,
+    generate_username_suggestions,
+    remove_special_characters_from_name,
+)
 
 
 @ddt.ddt
@@ -68,3 +72,73 @@ def test_safe_redirect_oauth2(self, client_redirect_uri, redirect_url, host, exp
         req = self.request.get(f'/logout?{urlencode(params)}', HTTP_HOST=host)
         actual_is_safe = self._is_safe_redirect(req, redirect_url)
         assert actual_is_safe == expected_is_safe
+
+
+@ddt.ddt
+class TestUsernameGeneration(TestCase):
+    """Test username generation utility methods."""
+
+    def test_remove_special_characters(self):
+        """Test the removal of special characters from a name."""
+        test_cases = [
+            ('John Doe', 'JohnDoe'),
+            ('John@Doe', 'JohnDoe'),
+            ('John.Doe', 'JohnDoe'),
+            ('John_Doe', 'John_Doe'),  # Underscore is allowed
+            ('John-Doe', 'John-Doe'),  # Hyphen is allowed
+            ('John$#@!Doe', 'JohnDoe'),
+        ]
+        for input_name, expected in test_cases:
+            assert remove_special_characters_from_name(input_name) == expected
+
+    @ddt.data(
+        # Test normal ASCII name
+        ('John Doe', True),  # Should return suggestions
+        ('Jane Smith', True),  # Should return suggestions
+        # Test non-ASCII names
+        ('José García', False),  # Contains non-ASCII characters
+        ('مریم میرزاخانی', False),  # Persian name
+        ('明美 田中', False),  # Japanese name
+        ('Σωκράτης', False),  # Greek name
+        ('Владимир', False),  # Cyrillic characters
+        # Test edge cases
+        ('A B', True),  # Minimal valid name
+        ('', True),  # Empty string
+        ('   ', True),  # Just spaces
+    )
+    @ddt.unpack
+    def test_username_suggestions_ascii_check(self, name, should_generate):
+        """Test username suggestion generation for ASCII and non-ASCII names."""
+        suggestions = generate_username_suggestions(name)
+
+        if should_generate:
+            if name.strip():  # If name is not empty or just spaces
+                # Should generate up to 3 suggestions for valid ASCII names
+                assert len(suggestions) <= 3
+                # Verify all suggestions are ASCII
+                for suggestion in suggestions:
+                    assert suggestion.isascii()
+                    assert suggestion.replace('_', '').replace('-', '').isalnum()
+            else:
+                # Empty or whitespace-only names should return empty list
+                assert not suggestions
+        else:
+            # Should return empty list for non-ASCII names
+            assert not suggestions
+
+    def test_unique_suggestions(self):
+        """Test that generated suggestions are unique."""
+        name = "John Doe"
+        suggestions = generate_username_suggestions(name)
+        assert len(suggestions) == len(set(suggestions)), "All suggestions should be unique"
+
+    def test_suggestion_length(self):
+        """Test that generated suggestions respect the maximum length."""
+        from openedx.core.djangoapps.user_api.accounts import USERNAME_MAX_LENGTH
+
+        # Test with a very long name
+        long_name = "John" * 50
+        suggestions = generate_username_suggestions(long_name)
+
+        for suggestion in suggestions:
+            assert len(suggestion) <= USERNAME_MAX_LENGTH

openedx/core/djangoapps/user_authn/utils.py

@@ -72,12 +72,35 @@ def is_registration_api_v1(request):
     return 'v1' in request.get_full_path() and 'register' not in request.get_full_path()
 
 
-def remove_special_characters_from_name(name):
+def remove_special_characters_from_name(name: str) -> str:
     return "".join(re.findall(r"[\w-]+", name))
 
 
-def generate_username_suggestions(name):
-    """ Generate 3 available username suggestions """
+def generate_username_suggestions(name: str) -> list[str] | list:
+    """
+    Generate 3 available username suggestions based on the provided name.
+
+    Args:
+        name (str): The full name to generate username suggestions from.
+            Must contain only ASCII characters.
+
+    Returns:
+        list[str] | list: A list of up to 3 available username suggestions,
+            or an empty list if name contains non-ASCII characters or if no valid
+            suggestions could be generated.
+
+    Note:
+        Generated usernames will be combinations of:
+        - firstname + lastname
+        - first initial + lastname
+        - firstname + random number
+    """
+    # Check if name contains non-ASCII characters
+    try:
+        name.encode('ascii')
+    except UnicodeEncodeError:
+        return []
+
     username_suggestions = []
     max_length = USERNAME_MAX_LENGTH
     names = name.split(' ')

openedx/core/djangoapps/user_authn/views/login.py

@@ -195,7 +195,7 @@ def _enforce_password_policy_compliance(request, user):  # lint-amnesty, pylint:
         # Allow login, but warn the user that they will be required to reset their password soon.
         PageLevelMessages.register_warning_message(request, HTML(str(e)))
     except password_policy_compliance.NonCompliantPasswordException as e:
-        # Increment the lockout counter to safguard from further brute force requests
+        # Increment the lockout counter to safeguard from further brute force requests
         # if user's password has been compromised.
         if LoginFailures.is_feature_enabled():
             LoginFailures.increment_lockout_counter(user)