test: add 150 new unit tests covering auth, users, notifications, logs, settings, GDPR, and Gmail label utilities

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Co-authored-by: christianlouis <361235+christianlouis@users.noreply.github.com>

backend/tests/unit/test_gdpr.py

@@ -0,0 +1,102 @@
+"""
+Unit tests for GDPR data masking utilities (core/gdpr.py).
+No database or HTTP layer required – pure function tests.
+"""
+
+
+from app.core.gdpr import mask_email, mask_name, mask_from_header
+
+
+class TestMaskEmail:
+    def test_typical_address(self):
+        assert mask_email("john.doe@example.com") == "jo***@e***.com"
+
+    def test_short_local(self):
+        # local part has only 1 char; still returns that char + ***
+        result = mask_email("a@b.de")
+        assert result == "a***@b***.de"
+
+    def test_two_char_local(self):
+        result = mask_email("ab@x.io")
+        assert result == "ab***@x***.io"
+
+    def test_domain_with_subdomain_tld(self):
+        # rsplit('.', 1) splits on the last dot only
+        result = mask_email("user@mail.example.org")
+        assert result == "us***@m***.org"
+
+    def test_empty_string(self):
+        assert mask_email("") == "***"
+
+    def test_no_at_sign(self):
+        assert mask_email("notanemail") == "***"
+
+    def test_preserves_tld(self):
+        result = mask_email("hello@world.co.uk")
+        assert result.endswith(".uk")
+
+    def test_single_char_sld(self):
+        result = mask_email("user@x.com")
+        assert result == "us***@x***.com"
+
+
+class TestMaskName:
+    def test_single_word(self):
+        assert mask_name("Alice") == "Al***"
+
+    def test_two_words(self):
+        assert mask_name("John Doe") == "Jo*** Do***"
+
+    def test_single_char_word(self):
+        result = mask_name("X")
+        assert result == "X***"
+
+    def test_empty_string(self):
+        assert mask_name("") == "***"
+
+    def test_three_words(self):
+        result = mask_name("Jean-Luc Picard")
+        # Two words separated by space
+        parts = result.split(" ")
+        assert len(parts) == 2
+        assert all(p.endswith("***") for p in parts)
+
+    def test_long_name(self):
+        result = mask_name("Alexander")
+        assert result == "Al***"
+
+
+class TestMaskFromHeader:
+    def test_display_name_with_angle_email(self):
+        result = mask_from_header("John Doe <john.doe@example.com>")
+        assert "<" in result
+        assert "jo***" in result
+        assert "Jo***" in result
+
+    def test_plain_email(self):
+        result = mask_from_header("john.doe@example.com")
+        assert result == "jo***@e***.com"
+
+    def test_empty_string(self):
+        assert mask_from_header("") == "***"
+
+    def test_no_display_name_angle_email(self):
+        result = mask_from_header("<user@example.com>")
+        assert result == "us***@e***.com"
+
+    def test_fallback_no_email_pattern(self):
+        # String with no recognisable email → falls back to mask_name
+        result = mask_from_header("JustAName")
+        assert result == "Ju***"
+
+    def test_quoted_display_name(self):
+        result = mask_from_header('"Alice Smith" <alice@example.com>')
+        assert "Al***" in result
+        assert "al***" in result
+
+    def test_angle_email_no_display(self):
+        # Edge: angle brackets but empty display part
+        result = mask_from_header("   <admin@site.org>")
+        # No display name → returns masked email only
+        assert "@" in result
+        assert "***" in result