chore: add not found case for GetUserByEmail test

store/storetest/storetest.go

@@ -55,6 +55,7 @@ func RunSuite(t *testing.T, newStore Factory) {
 		{"CreateUser_duplicateEmail", testCreateUserDuplicateEmail},
 		{"CreateUser_duplicateUsernameNormalized", testCreateUserDuplicateUsernameNormalized},
 		{"CreateUser_GetUserByEmail_roundTrip", testCreateUserGetUserByEmailRoundTrip},
+		{"GetUserByEmail_notFound", testGetUserByEmailNotFound},
 	}
 
 	for _, tc := range cases {
@@ -156,6 +157,16 @@ func testCreateUserGetUserByEmailRoundTrip(t *testing.T, s SuiteStore) {
 	AssertUserEqual(t, got, want)
 }
 
+func testGetUserByEmailNotFound(t *testing.T, s SuiteStore) {
+	got, err := s.GetUserByEmail(context.Background(), "does-not-exist@mail.com")
+	if err == nil {
+		t.Fatalf("expected error, got user %+v", got)
+	}
+	if !errors.Is(err, store.ErrUserNotFound) {
+		t.Errorf("expected ErrUserNotFound, got: %v", err)
+	}
+}
+
 // ---------------------------------------------------------------------------
 // Fixtures and helpers. Exported so dialect-specific tests can reuse them
 // for one-off cases that don't fit into the shared suite.