feat: mail service

integration/authsessionuser/authsession_user_test.go

@@ -64,6 +64,31 @@ func TestAuthsessionUserBlackBoxConfirmForExistingUserKeepsCreateOnlySettings(t
 	require.Equal(t, "Europe/Paris", account.User.TimeZone)
 }
 
+func TestAuthsessionUserBlackBoxAcceptLanguageSetsLocalizedPreferredLanguage(t *testing.T) {
+	t.Parallel()
+
+	h := newAuthsessionUserHarness(t)
+	email := "localized@example.com"
+
+	challengeID := h.sendChallengeWithAcceptLanguage(t, email, "fr-FR, en;q=0.8")
+	deliveries := h.mailStub.RecordedDeliveries()
+	require.NotEmpty(t, deliveries)
+	require.Equal(t, "fr-FR", deliveries[len(deliveries)-1].Locale)
+
+	code := lastMailCodeFor(t, h.mailStub, email)
+	response := h.confirmCode(t, challengeID, code)
+	var confirmBody struct {
+		DeviceSessionID string `json:"device_session_id"`
+	}
+	requireJSONStatus(t, response, http.StatusOK, &confirmBody)
+	require.True(t, strings.HasPrefix(confirmBody.DeviceSessionID, "device-session-"))
+
+	lookupResponse, account := lookupUserByEmail(t, h.userServiceURL, email)
+	require.Equalf(t, http.StatusOK, lookupResponse.StatusCode, formatStatusError(lookupResponse))
+	require.Equal(t, "fr-FR", account.User.PreferredLanguage)
+	require.Equal(t, testTimeZone, account.User.TimeZone)
+}
+
 func TestAuthsessionUserBlackBoxBlockedEmailSendIsSuccessShapedAndConfirmIsRejectedWithoutCreatingUser(t *testing.T) {
 	t.Parallel()