Removed excess spaces from the test_change_date test of the JournalEntryReorderTestCase test case.

src/accounting/templates/accounting/journal-entry/include/description-editor-modal.html

@@ -19,7 +19,8 @@ description-editor-modal.html: The modal of the description editor
 Author: imacat@mail.imacat.idv.tw (imacat)
 First written: 2023/2/28
 #}
-<form id="accounting-description-editor-{{ description_editor.debit_credit }}" class="accounting-description-editor" name="accounting-dummy-form" data-debit-credit="{{ description_editor.debit_credit }}">
+<form id="accounting-description-editor-{{ description_editor.debit_credit }}" class="accounting-description-editor" data-debit-credit="{{ description_editor.debit_credit }}">
+  <input type="hidden" name="csrf_token" value="{{ csrf_token() }}">
   <div id="accounting-description-editor-{{ description_editor.debit_credit }}-modal" class="modal fade" tabindex="-1" aria-labelledby="accounting-description-editor-{{ description_editor.debit_credit }}-modal-label" aria-hidden="true">
     <div class="modal-dialog">
       <div class="modal-content">

src/accounting/templates/accounting/journal-entry/include/journal-entry-line-item-editor-modal.html

@@ -19,7 +19,8 @@ journal-entry-line-item-editor-modal: The modal of the journal entry line item e
 Author: imacat@mail.imacat.idv.tw (imacat)
 First written: 2023/2/25
 #}
-<form id="accounting-line-item-editor" name="accounting-dummy-form">
+<form id="accounting-line-item-editor">
+  <input type="hidden" name="csrf_token" value="{{ csrf_token() }}">
   <div id="accounting-line-item-editor-modal" class="modal fade" tabindex="-1" aria-labelledby="accounting-line-item-editor-modal-label" aria-hidden="true">
     <div class="modal-dialog">
       <div class="modal-content">

src/accounting/templates/accounting/option/include/recurring-item-editor-modal.html

@@ -19,7 +19,8 @@ recurring-item-editor-modal.html: The modal of the recurring item editor
 Author: imacat@mail.imacat.idv.tw (imacat)
 First written: 2023/3/22
 #}
-<form id="accounting-recurring-item-editor-{{ expense_income }}" name="accounting-dummy-form">
+<form id="accounting-recurring-item-editor-{{ expense_income }}">
+  <input type="hidden" name="csrf_token" value="{{ csrf_token() }}">
   <div id="accounting-recurring-item-editor-{{ expense_income }}-modal" class="modal fade" tabindex="-1" aria-labelledby="accounting-recurring-item-editor-{{ expense_income }}-modal-label" aria-hidden="true">
     <div class="modal-dialog">
       <div class="modal-content">

src/accounting/utils/next_uri.py

@@ -22,7 +22,8 @@ This module should not import any other module from the application.
 from urllib.parse import urlparse, parse_qsl, ParseResult, urlencode, \
     urlunparse
 
-from flask import request, Blueprint
+from flask import request, Blueprint, current_app
+from itsdangerous import URLSafeSerializer, BadData
 
 
 def append_next(uri: str) -> str:
@@ -41,7 +42,7 @@ def inherit_next(uri: str) -> str:
     :param uri: The URI.
     :return: The URI with the current next URI added at the query argument.
     """
-    next_uri: str | None = __get_next_uri()
+    next_uri: str | None = __get_next()
     return uri if next_uri is None else __set_next(uri, next_uri)
 
 
@@ -51,20 +52,24 @@ def or_next(uri: str) -> str:
     :param uri: The URI.
     :return: The next URI or the supplied URI.
     """
-    next_uri: str | None = __get_next_uri()
+    next_uri: str | None = __get_next()
     return uri if next_uri is None else next_uri
 
 
-def __get_next_uri() -> str | None:
+def __get_next() -> str | None:
     """Returns the valid next URI.
 
     :return: The valid next URI.
     """
     next_uri: str | None = request.form.get("next") \
         if request.method == "POST" else request.args.get("next")
-    if next_uri is None or not next_uri.startswith("/"):
+    if next_uri is None:
+        return None
+    try:
+        return URLSafeSerializer(current_app.config["SECRET_KEY"])\
+            .loads(next_uri, "next")
+    except BadData:
         return None
-    return next_uri
 
 
 def __set_next(uri: str, next_uri: str) -> str:
@@ -77,12 +82,22 @@ def __set_next(uri: str, next_uri: str) -> str:
     uri_p: ParseResult = urlparse(uri)
     params: list[tuple[str, str]] = parse_qsl(uri_p.query)
     params = [x for x in params if x[0] != "next"]
-    params.append(("next", next_uri))
+    params.append(("next", encode_next(next_uri)))
     parts: list[str] = list(uri_p)
     parts[4] = urlencode(params)
     return urlunparse(parts)
 
 
+def encode_next(uri: str) -> str:
+    """Encodes the next URI.
+
+    :param uri: The next URI.
+    :return: The encoded next URI.
+    """
+    return URLSafeSerializer(current_app.config["SECRET_KEY"])\
+        .dumps(uri, "next")
+
+
 def init_app(bp: Blueprint) -> None:
     """Initializes the application.
 

tests/test_account.py

@@ -23,6 +23,7 @@ import unittest
 import httpx
 from flask import Flask
 
+from accounting.utils.next_uri import encode_next
 from test_site import db
 from testlib import NEXT_URI, create_test_app, get_client, set_locale, \
     add_journal_entry
@@ -78,6 +79,7 @@ class AccountTestCase(unittest.TestCase):
             AccountL10n.query.delete()
             Account.query.delete()
             db.session.commit()
+            self.encoded_next_uri: str = encode_next(NEXT_URI)
 
         self.client, self.csrf_token = get_client(self.app, "editor")
         response: httpx.Response
@@ -143,7 +145,7 @@ class AccountTestCase(unittest.TestCase):
 
         response = client.post(f"{PREFIX}/bases/{CASH.base_code}",
                                data={"csrf_token": csrf_token,
-                                     "next": NEXT_URI,
+                                     "next": self.encoded_next_uri,
                                      f"{cash_id}-no": "5"})
         self.assertEqual(response.status_code, 403)
 
@@ -192,7 +194,7 @@ class AccountTestCase(unittest.TestCase):
 
         response = client.post(f"{PREFIX}/bases/{CASH.base_code}",
                                data={"csrf_token": csrf_token,
-                                     "next": NEXT_URI,
+                                     "next": self.encoded_next_uri,
                                      f"{cash_id}-no": "5"})
         self.assertEqual(response.status_code, 403)
 
@@ -244,7 +246,7 @@ class AccountTestCase(unittest.TestCase):
 
         response = self.client.post(f"{PREFIX}/bases/{CASH.base_code}",
                                     data={"csrf_token": self.csrf_token,
-                                          "next": NEXT_URI,
+                                          "next": self.encoded_next_uri,
                                           f"{cash_id}-no": "5"})
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], NEXT_URI)
@@ -526,7 +528,7 @@ class AccountTestCase(unittest.TestCase):
             self.assertEqual(account.title_l10n, CASH.title)
             self.assertEqual(account.l10n, [])
 
-        set_locale(self.client, self.csrf_token, "zh_Hant")
+        set_locale(self.app, self.client, self.csrf_token, "zh_Hant")
 
         response = self.client.post(update_uri,
                                     data={"csrf_token": self.csrf_token,
@@ -541,7 +543,7 @@ class AccountTestCase(unittest.TestCase):
             self.assertEqual({(x.locale, x.title) for x in account.l10n},
                              {("zh_Hant", f"{CASH.title}-zh_Hant")})
 
-        set_locale(self.client, self.csrf_token, "en")
+        set_locale(self.app, self.client, self.csrf_token, "en")
 
         response = self.client.post(update_uri,
                                     data={"csrf_token": self.csrf_token,
@@ -556,7 +558,7 @@ class AccountTestCase(unittest.TestCase):
             self.assertEqual({(x.locale, x.title) for x in account.l10n},
                              {("zh_Hant", f"{CASH.title}-zh_Hant")})
 
-        set_locale(self.client, self.csrf_token, "zh_Hant")
+        set_locale(self.app, self.client, self.csrf_token, "zh_Hant")
 
         response = self.client.post(update_uri,
                                     data={"csrf_token": self.csrf_token,
@@ -591,7 +593,7 @@ class AccountTestCase(unittest.TestCase):
 
         add_journal_entry(self.client,
                           form={"csrf_token": self.csrf_token,
-                                "next": NEXT_URI,
+                                "next": self.encoded_next_uri,
                                 "date": dt.date.today().isoformat(),
                                 "currency-1-code": "USD",
                                 "currency-1-credit-1-account_code": BANK.code,
@@ -709,7 +711,7 @@ class AccountTestCase(unittest.TestCase):
 
         response = self.client.post(f"{PREFIX}/bases/1111",
                                     data={"csrf_token": self.csrf_token,
-                                          "next": NEXT_URI,
+                                          "next": self.encoded_next_uri,
                                           f"{id_1}-no": "4",
                                           f"{id_2}-no": "1",
                                           f"{id_3}-no": "5",
@@ -736,7 +738,7 @@ class AccountTestCase(unittest.TestCase):
 
         response = self.client.post(f"{PREFIX}/bases/1111",
                                     data={"csrf_token": self.csrf_token,
-                                          "next": NEXT_URI,
+                                          "next": self.encoded_next_uri,
                                           f"{id_2}-no": "3a",
                                           f"{id_3}-no": "5",
                                           f"{id_4}-no": "2"})

tests/test_currency.py

@@ -23,6 +23,7 @@ import unittest
 import httpx
 from flask import Flask
 
+from accounting.utils.next_uri import encode_next
 from test_site import db
 from testlib import NEXT_URI, create_test_app, get_client, set_locale, \
     add_journal_entry
@@ -468,7 +469,7 @@ class CurrencyTestCase(unittest.TestCase):
             self.assertEqual(currency.name_l10n, USD.name)
             self.assertEqual(currency.l10n, [])
 
-        set_locale(self.client, self.csrf_token, "zh_Hant")
+        set_locale(self.app, self.client, self.csrf_token, "zh_Hant")
 
         response = self.client.post(update_uri,
                                     data={"csrf_token": self.csrf_token,
@@ -483,7 +484,7 @@ class CurrencyTestCase(unittest.TestCase):
             self.assertEqual({(x.locale, x.name) for x in currency.l10n},
                              {("zh_Hant", f"{USD.name}-zh_Hant")})
 
-        set_locale(self.client, self.csrf_token, "en")
+        set_locale(self.app, self.client, self.csrf_token, "en")
 
         response = self.client.post(update_uri,
                                     data={"csrf_token": self.csrf_token,
@@ -498,7 +499,7 @@ class CurrencyTestCase(unittest.TestCase):
             self.assertEqual({(x.locale, x.name) for x in currency.l10n},
                              {("zh_Hant", f"{USD.name}-zh_Hant")})
 
-        set_locale(self.client, self.csrf_token, "zh_Hant")
+        set_locale(self.app, self.client, self.csrf_token, "zh_Hant")
 
         response = self.client.post(update_uri,
                                     data={"csrf_token": self.csrf_token,
@@ -521,6 +522,8 @@ class CurrencyTestCase(unittest.TestCase):
         from accounting.models import Currency
         detail_uri: str = f"{PREFIX}/{JPY.code}"
         delete_uri: str = f"{PREFIX}/{JPY.code}/delete"
+        with self.app.app_context():
+            encoded_next_uri: str = encode_next(NEXT_URI)
         list_uri: str = PREFIX
         response: httpx.Response
 
@@ -533,7 +536,7 @@ class CurrencyTestCase(unittest.TestCase):
 
         add_journal_entry(self.client,
                           form={"csrf_token": self.csrf_token,
-                                "next": NEXT_URI,
+                                "next": encoded_next_uri,
                                 "date": dt.date.today().isoformat(),
                                 "currency-1-code": EUR.code,
                                 "currency-1-credit-1-account_code": "1111-001",

tests/test_description_editor.py

@@ -22,6 +22,7 @@ import unittest
 
 from flask import Flask
 
+from accounting.utils.next_uri import encode_next
 from testlib import NEXT_URI, Accounts, create_test_app, get_client, \
     add_journal_entry
 
@@ -41,6 +42,7 @@ class DescriptionEditorTestCase(unittest.TestCase):
             from accounting.models import JournalEntry, JournalEntryLineItem
             JournalEntry.query.delete()
             JournalEntryLineItem.query.delete()
+            self.encoded_next_uri: str = encode_next(NEXT_URI)
 
         self.client, self.csrf_token = get_client(self.app, "editor")
 
@@ -51,7 +53,7 @@ class DescriptionEditorTestCase(unittest.TestCase):
         """
         from accounting.journal_entry.utils.description_editor import \
             DescriptionEditor
-        for form in get_form_data(self.csrf_token):
+        for form in get_form_data(self.csrf_token, self.encoded_next_uri):
             add_journal_entry(self.client, form)
         with self.app.app_context():
             editor: DescriptionEditor = DescriptionEditor()
@@ -143,22 +145,24 @@ class DescriptionEditorTestCase(unittest.TestCase):
                          Accounts.PREPAID)
 
 
-def get_form_data(csrf_token: str) -> list[dict[str, str]]:
+def get_form_data(csrf_token: str, encoded_next_uri: str) \
+        -> list[dict[str, str]]:
     """Returns the form data for multiple journal entry forms.
 
     :param csrf_token: The CSRF token.
+    :param encoded_next_uri: The encoded next URI.
     :return: A list of the form data.
     """
     journal_entry_date: str = dt.date.today().isoformat()
     return [{"csrf_token": csrf_token,
-             "next": NEXT_URI,
+             "next": encoded_next_uri,
              "date": journal_entry_date,
              "currency-0-code": "USD",
              "currency-0-credit-0-account_code": Accounts.SERVICE,
              "currency-0-credit-0-description": " Salary ",
              "currency-0-credit-0-amount": "2500"},
             {"csrf_token": csrf_token,
-             "next": NEXT_URI,
+             "next": encoded_next_uri,
              "date": journal_entry_date,
              "currency-0-code": "USD",
              "currency-0-debit-0-account_code": Accounts.MEAL,
@@ -180,7 +184,7 @@ def get_form_data(csrf_token: str) -> list[dict[str, str]]:
              "currency-0-credit-2-description": " Dinner—Hamburger ",
              "currency-0-credit-2-amount": "4.25"},
             {"csrf_token": csrf_token,
-             "next": NEXT_URI,
+             "next": encoded_next_uri,
              "date": journal_entry_date,
              "currency-0-code": "USD",
              "currency-0-debit-0-account_code": Accounts.MEAL,
@@ -196,7 +200,7 @@ def get_form_data(csrf_token: str) -> list[dict[str, str]]:
              "currency-0-credit-1-description": " Dinner—Steak ",
              "currency-0-credit-1-amount": "8.28"},
             {"csrf_token": csrf_token,
-             "next": NEXT_URI,
+             "next": encoded_next_uri,
              "date": journal_entry_date,
              "currency-0-code": "USD",
              "currency-0-debit-0-account_code": Accounts.MEAL,
@@ -212,14 +216,14 @@ def get_form_data(csrf_token: str) -> list[dict[str, str]]:
              "currency-0-credit-1-description": " Lunch—Noodles ",
              "currency-0-credit-1-amount": "7.47"},
             {"csrf_token": csrf_token,
-             "next": NEXT_URI,
+             "next": encoded_next_uri,
              "date": journal_entry_date,
              "currency-0-code": "USD",
              "currency-0-debit-0-account_code": Accounts.TRAVEL,
              "currency-0-debit-0-description": " Airplane—Lake City↔Hill Town",
              "currency-0-debit-0-amount": "800"},
             {"csrf_token": csrf_token,
-             "next": NEXT_URI,
+             "next": encoded_next_uri,
              "date": journal_entry_date,
              "currency-0-code": "USD",
              "currency-0-debit-0-account_code": Accounts.TRAVEL,
@@ -247,7 +251,7 @@ def get_form_data(csrf_token: str) -> list[dict[str, str]]:
              "currency-0-credit-3-description": " Train—Red—Mall→Museum ",
              "currency-0-credit-3-amount": "4.4"},
             {"csrf_token": csrf_token,
-             "next": NEXT_URI,
+             "next": encoded_next_uri,
              "date": journal_entry_date,
              "currency-0-code": "USD",
              "currency-0-debit-0-account_code": Accounts.TRAVEL,
@@ -293,7 +297,7 @@ def get_form_data(csrf_token: str) -> list[dict[str, str]]:
              "currency-0-credit-6-description": " Bike—Theatre→Home ",
              "currency-0-credit-6-amount": "5.5"},
             {"csrf_token": csrf_token,
-             "next": NEXT_URI,
+             "next": encoded_next_uri,
              "date": journal_entry_date,
              "currency-0-code": "USD",
              "currency-0-debit-0-account_code": Accounts.PETTY_CASH,

tests/test_journal_entry.py

@@ -24,6 +24,7 @@ from decimal import Decimal
 import httpx
 from flask import Flask
 
+from accounting.utils.next_uri import encode_next
 from test_site import db
 from testlib import NEXT_URI, Accounts, create_test_app, get_client, \
     add_journal_entry, match_journal_entry_detail
@@ -53,6 +54,7 @@ class CashReceiptJournalEntryTestCase(unittest.TestCase):
             from accounting.models import JournalEntry, JournalEntryLineItem
             JournalEntry.query.delete()
             JournalEntryLineItem.query.delete()
+            self.encoded_next_uri: str = encode_next(NEXT_URI)
 
         self.client, self.csrf_token = get_client(self.app, "editor")
 
@@ -153,7 +155,8 @@ class CashReceiptJournalEntryTestCase(unittest.TestCase):
                                     data=update_form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"],
-                         f"{PREFIX}/{journal_entry_id}?next=%2F_next")
+                         f"{PREFIX}/{journal_entry_id}?"
+                         f"next={self.encoded_next_uri}")
 
         response = self.client.post(f"{PREFIX}/{journal_entry_id}/delete",
                                     data={"csrf_token": self.csrf_token})
@@ -166,7 +169,8 @@ class CashReceiptJournalEntryTestCase(unittest.TestCase):
         :return: None.
         """
         from accounting.models import JournalEntry, JournalEntryCurrency
-        create_uri: str = f"{PREFIX}/create/receipt?next=%2F_next"
+        create_uri: str = (f"{PREFIX}/create/receipt?"
+                           f"next={self.encoded_next_uri}")
         store_uri: str = f"{PREFIX}/store/receipt"
         response: httpx.Response
         form: dict[str, str]
@@ -322,8 +326,10 @@ class CashReceiptJournalEntryTestCase(unittest.TestCase):
         from accounting.models import JournalEntry, JournalEntryCurrency
         journal_entry_id: int \
             = add_journal_entry(self.client, self.__get_add_form())
-        detail_uri: str = f"{PREFIX}/{journal_entry_id}?next=%2F_next"
-        edit_uri: str = f"{PREFIX}/{journal_entry_id}/edit?next=%2F_next"
+        detail_uri: str = (f"{PREFIX}/{journal_entry_id}?"
+                           f"next={self.encoded_next_uri}")
+        edit_uri: str = (f"{PREFIX}/{journal_entry_id}/edit?"
+                         f"next={self.encoded_next_uri}")
         update_uri: str = f"{PREFIX}/{journal_entry_id}/update"
         form_0: dict[str, str] = self.__get_update_form(journal_entry_id)
 
@@ -485,7 +491,8 @@ class CashReceiptJournalEntryTestCase(unittest.TestCase):
         from accounting.models import JournalEntry
         journal_entry_id: int \
             = add_journal_entry(self.client, self.__get_add_form())
-        detail_uri: str = f"{PREFIX}/{journal_entry_id}?next=%2F_next"
+        detail_uri: str = (f"{PREFIX}/{journal_entry_id}?"
+                           f"next={self.encoded_next_uri}")
         update_uri: str = f"{PREFIX}/{journal_entry_id}/update"
         journal_entry: JournalEntry
         response: httpx.Response
@@ -524,7 +531,8 @@ class CashReceiptJournalEntryTestCase(unittest.TestCase):
             = add_journal_entry(self.client, self.__get_add_form())
         editor_username, admin_username = "editor", "admin"
         client, csrf_token = get_client(self.app, admin_username)
-        detail_uri: str = f"{PREFIX}/{journal_entry_id}?next=%2F_next"
+        detail_uri: str = (f"{PREFIX}/{journal_entry_id}?"
+                           f"next={self.encoded_next_uri}")
         update_uri: str = f"{PREFIX}/{journal_entry_id}/update"
         journal_entry: JournalEntry
         response: httpx.Response
@@ -557,7 +565,8 @@ class CashReceiptJournalEntryTestCase(unittest.TestCase):
         from accounting.models import JournalEntry, JournalEntryLineItem
         journal_entry_id_1: int \
             = add_journal_entry(self.client, self.__get_add_form())
-        detail_uri: str = f"{PREFIX}/{journal_entry_id_1}?next=%2F_next"
+        detail_uri: str = (f"{PREFIX}/{journal_entry_id_1}?"
+                           f"next={self.encoded_next_uri}")
         delete_uri: str = f"{PREFIX}/{journal_entry_id_1}/delete"
         response: httpx.Response
 
@@ -575,7 +584,7 @@ class CashReceiptJournalEntryTestCase(unittest.TestCase):
         add_journal_entry(
             self.client,
             form={"csrf_token": self.csrf_token,
-                  "next": NEXT_URI,
+                  "next": self.encoded_next_uri,
                   "date": dt.date.today().isoformat(),
                   "currency-1-code": line_item.currency_code,
                   "currency-1-debit-1-original_line_item_id": line_item.id,
@@ -585,17 +594,18 @@ class CashReceiptJournalEntryTestCase(unittest.TestCase):
         # Cannot delete the journal entry that is in use
         response = self.client.post(f"{PREFIX}/{journal_entry_id_2}/delete",
                                     data={"csrf_token": self.csrf_token,
-                                          "next": NEXT_URI})
+                                          "next": self.encoded_next_uri})
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"],
-                         f"{PREFIX}/{journal_entry_id_2}?next=%2F_next")
+                         f"{PREFIX}/{journal_entry_id_2}?"
+                         f"next={self.encoded_next_uri}")
 
         # Success
         response = self.client.get(detail_uri)
         self.assertEqual(response.status_code, 200)
         response = self.client.post(delete_uri,
                                     data={"csrf_token": self.csrf_token,
-                                          "next": NEXT_URI})
+                                          "next": self.encoded_next_uri})
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], NEXT_URI)
 
@@ -603,7 +613,7 @@ class CashReceiptJournalEntryTestCase(unittest.TestCase):
         self.assertEqual(response.status_code, 404)
         response = self.client.post(delete_uri,
                                     data={"csrf_token": self.csrf_token,
-                                          "next": NEXT_URI})
+                                          "next": self.encoded_next_uri})
         self.assertEqual(response.status_code, 404)
 
     def __get_add_form(self) -> dict[str, str]:
@@ -611,7 +621,8 @@ class CashReceiptJournalEntryTestCase(unittest.TestCase):
 
         :return: The form data to add a new journal entry.
         """
-        form: dict[str, str] = get_add_form(self.csrf_token)
+        form: dict[str, str] = get_add_form(self.csrf_token,
+                                            self.encoded_next_uri)
         form = {x: form[x] for x in form if "-debit-" not in x}
         return form
 
@@ -625,7 +636,7 @@ class CashReceiptJournalEntryTestCase(unittest.TestCase):
             not changed.
         """
         form: dict[str, str] = get_unchanged_update_form(
-            journal_entry_id, self.app, self.csrf_token)
+            journal_entry_id, self.app, self.csrf_token, self.encoded_next_uri)
         form = {x: form[x] for x in form if "-debit-" not in x}
         return form
 
@@ -638,7 +649,8 @@ class CashReceiptJournalEntryTestCase(unittest.TestCase):
             changed.
         """
         form: dict[str, str] = get_update_form(
-            journal_entry_id, self.app, self.csrf_token, False)
+            journal_entry_id, self.app, self.csrf_token, self.encoded_next_uri,
+            False)
         form = {x: form[x] for x in form if "-debit-" not in x}
         return form
 
@@ -658,6 +670,7 @@ class CashDisbursementJournalEntryTestCase(unittest.TestCase):
             from accounting.models import JournalEntry, JournalEntryLineItem
             JournalEntry.query.delete()
             JournalEntryLineItem.query.delete()
+            self.encoded_next_uri: str = encode_next(NEXT_URI)
 
         self.client, self.csrf_token = get_client(self.app, "editor")
 
@@ -758,7 +771,8 @@ class CashDisbursementJournalEntryTestCase(unittest.TestCase):
                                     data=update_form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"],
-                         f"{PREFIX}/{journal_entry_id}?next=%2F_next")
+                         f"{PREFIX}/{journal_entry_id}?"
+                         f"next={self.encoded_next_uri}")
 
         response = self.client.post(f"{PREFIX}/{journal_entry_id}/delete",
                                     data={"csrf_token": self.csrf_token})
@@ -771,7 +785,8 @@ class CashDisbursementJournalEntryTestCase(unittest.TestCase):
         :return: None.
         """
         from accounting.models import JournalEntry, JournalEntryCurrency
-        create_uri: str = f"{PREFIX}/create/disbursement?next=%2F_next"
+        create_uri: str = (f"{PREFIX}/create/disbursement?"
+                           f"next={self.encoded_next_uri}")
         store_uri: str = f"{PREFIX}/store/disbursement"
         response: httpx.Response
         form: dict[str, str]
@@ -930,8 +945,10 @@ class CashDisbursementJournalEntryTestCase(unittest.TestCase):
         from accounting.models import JournalEntry, JournalEntryCurrency
         journal_entry_id: int \
             = add_journal_entry(self.client, self.__get_add_form())
-        detail_uri: str = f"{PREFIX}/{journal_entry_id}?next=%2F_next"
-        edit_uri: str = f"{PREFIX}/{journal_entry_id}/edit?next=%2F_next"
+        detail_uri: str = (f"{PREFIX}/{journal_entry_id}?"
+                           f"next={self.encoded_next_uri}")
+        edit_uri: str = (f"{PREFIX}/{journal_entry_id}/edit?"
+                         f"next={self.encoded_next_uri}")
         update_uri: str = f"{PREFIX}/{journal_entry_id}/update"
         form_0: dict[str, str] = self.__get_update_form(journal_entry_id)
 
@@ -1097,7 +1114,8 @@ class CashDisbursementJournalEntryTestCase(unittest.TestCase):
         from accounting.models import JournalEntry
         journal_entry_id: int \
             = add_journal_entry(self.client, self.__get_add_form())
-        detail_uri: str = f"{PREFIX}/{journal_entry_id}?next=%2F_next"
+        detail_uri: str = (f"{PREFIX}/{journal_entry_id}?"
+                           f"next={self.encoded_next_uri}")
         update_uri: str = f"{PREFIX}/{journal_entry_id}/update"
         journal_entry: JournalEntry
         response: httpx.Response
@@ -1136,7 +1154,8 @@ class CashDisbursementJournalEntryTestCase(unittest.TestCase):
             = add_journal_entry(self.client, self.__get_add_form())
         editor_username, admin_username = "editor", "admin"
         client, csrf_token = get_client(self.app, admin_username)
-        detail_uri: str = f"{PREFIX}/{journal_entry_id}?next=%2F_next"
+        detail_uri: str = (f"{PREFIX}/{journal_entry_id}?"
+                           f"next={self.encoded_next_uri}")
         update_uri: str = f"{PREFIX}/{journal_entry_id}/update"
         journal_entry: JournalEntry
         response: httpx.Response
@@ -1168,7 +1187,8 @@ class CashDisbursementJournalEntryTestCase(unittest.TestCase):
         """
         journal_entry_id: int \
             = add_journal_entry(self.client, self.__get_add_form())
-        detail_uri: str = f"{PREFIX}/{journal_entry_id}?next=%2F_next"
+        detail_uri: str = (f"{PREFIX}/{journal_entry_id}?"
+                           f"next={self.encoded_next_uri}")
         delete_uri: str = f"{PREFIX}/{journal_entry_id}/delete"
         response: httpx.Response
 
@@ -1176,7 +1196,7 @@ class CashDisbursementJournalEntryTestCase(unittest.TestCase):
         self.assertEqual(response.status_code, 200)
         response = self.client.post(delete_uri,
                                     data={"csrf_token": self.csrf_token,
-                                          "next": NEXT_URI})
+                                          "next": self.encoded_next_uri})
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], NEXT_URI)
 
@@ -1184,7 +1204,7 @@ class CashDisbursementJournalEntryTestCase(unittest.TestCase):
         self.assertEqual(response.status_code, 404)
         response = self.client.post(delete_uri,
                                     data={"csrf_token": self.csrf_token,
-                                          "next": NEXT_URI})
+                                          "next": self.encoded_next_uri})
         self.assertEqual(response.status_code, 404)
 
     def __get_add_form(self) -> dict[str, str]:
@@ -1192,7 +1212,8 @@ class CashDisbursementJournalEntryTestCase(unittest.TestCase):
 
         :return: The form data to add a new journal entry.
         """
-        form: dict[str, str] = get_add_form(self.csrf_token)
+        form: dict[str, str] = get_add_form(self.csrf_token,
+                                            self.encoded_next_uri)
         form = {x: form[x] for x in form if "-credit-" not in x}
         return form
 
@@ -1206,7 +1227,7 @@ class CashDisbursementJournalEntryTestCase(unittest.TestCase):
             not changed.
         """
         form: dict[str, str] = get_unchanged_update_form(
-            journal_entry_id, self.app, self.csrf_token)
+            journal_entry_id, self.app, self.csrf_token, self.encoded_next_uri)
         form = {x: form[x] for x in form if "-credit-" not in x}
         return form
 
@@ -1219,7 +1240,8 @@ class CashDisbursementJournalEntryTestCase(unittest.TestCase):
             changed.
         """
         form: dict[str, str] = get_update_form(
-            journal_entry_id, self.app, self.csrf_token, True)
+            journal_entry_id, self.app, self.csrf_token, self.encoded_next_uri,
+            True)
         form = {x: form[x] for x in form if "-credit-" not in x}
         return form
 
@@ -1240,6 +1262,7 @@ class TransferJournalEntryTestCase(unittest.TestCase):
                 JournalEntryLineItem
             JournalEntry.query.delete()
             JournalEntryLineItem.query.delete()
+            self.encoded_next_uri: str = encode_next(NEXT_URI)
 
         self.client, self.csrf_token = get_client(self.app, "editor")
 
@@ -1340,7 +1363,8 @@ class TransferJournalEntryTestCase(unittest.TestCase):
                                     data=update_form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"],
-                         f"{PREFIX}/{journal_entry_id}?next=%2F_next")
+                         f"{PREFIX}/{journal_entry_id}?"
+                         f"next={self.encoded_next_uri}")
 
         response = self.client.post(f"{PREFIX}/{journal_entry_id}/delete",
                                     data={"csrf_token": self.csrf_token})
@@ -1353,7 +1377,8 @@ class TransferJournalEntryTestCase(unittest.TestCase):
         :return: None.
         """
         from accounting.models import JournalEntry, JournalEntryCurrency
-        create_uri: str = f"{PREFIX}/create/transfer?next=%2F_next"
+        create_uri: str = (f"{PREFIX}/create/transfer?"
+                           f"next={self.encoded_next_uri}")
         store_uri: str = f"{PREFIX}/store/transfer"
         response: httpx.Response
         form: dict[str, str]
@@ -1548,8 +1573,10 @@ class TransferJournalEntryTestCase(unittest.TestCase):
         from accounting.models import JournalEntry, JournalEntryCurrency
         journal_entry_id: int \
             = add_journal_entry(self.client, self.__get_add_form())
-        detail_uri: str = f"{PREFIX}/{journal_entry_id}?next=%2F_next"
-        edit_uri: str = f"{PREFIX}/{journal_entry_id}/edit?next=%2F_next"
+        detail_uri: str = (f"{PREFIX}/{journal_entry_id}?"
+                           f"next={self.encoded_next_uri}")
+        edit_uri: str = (f"{PREFIX}/{journal_entry_id}/edit?"
+                         f"next={self.encoded_next_uri}")
         update_uri: str = f"{PREFIX}/{journal_entry_id}/update"
         form_0: dict[str, str] = self.__get_update_form(journal_entry_id)
 
@@ -1758,7 +1785,8 @@ class TransferJournalEntryTestCase(unittest.TestCase):
         from accounting.models import JournalEntry
         journal_entry_id: int \
             = add_journal_entry(self.client, self.__get_add_form())
-        detail_uri: str = f"{PREFIX}/{journal_entry_id}?next=%2F_next"
+        detail_uri: str = (f"{PREFIX}/{journal_entry_id}?"
+                           f"next={self.encoded_next_uri}")
         update_uri: str = f"{PREFIX}/{journal_entry_id}/update"
         journal_entry: JournalEntry
         response: httpx.Response
@@ -1797,7 +1825,8 @@ class TransferJournalEntryTestCase(unittest.TestCase):
             = add_journal_entry(self.client, self.__get_add_form())
         editor_username, admin_username = "editor", "admin"
         client, csrf_token = get_client(self.app, admin_username)
-        detail_uri: str = f"{PREFIX}/{journal_entry_id}?next=%2F_next"
+        detail_uri: str = (f"{PREFIX}/{journal_entry_id}?"
+                           f"next={self.encoded_next_uri}")
         update_uri: str = f"{PREFIX}/{journal_entry_id}/update"
         journal_entry: JournalEntry
         response: httpx.Response
@@ -1831,7 +1860,8 @@ class TransferJournalEntryTestCase(unittest.TestCase):
         from accounting.models import JournalEntry, JournalEntryCurrency
         journal_entry_id: int \
             = add_journal_entry(self.client, self.__get_add_form())
-        detail_uri: str = f"{PREFIX}/{journal_entry_id}?next=%2F_next"
+        detail_uri: str = (f"{PREFIX}/{journal_entry_id}?"
+                           f"next={self.encoded_next_uri}")
         update_uri: str = f"{PREFIX}/{journal_entry_id}/update?as=receipt"
         form_0: dict[str, str] = self.__get_update_form(journal_entry_id)
         form_0 = {x: form_0[x] for x in form_0 if "-debit-" not in x}
@@ -1932,7 +1962,8 @@ class TransferJournalEntryTestCase(unittest.TestCase):
         from accounting.models import JournalEntry, JournalEntryCurrency
         journal_entry_id: int \
             = add_journal_entry(self.client, self.__get_add_form())
-        detail_uri: str = f"{PREFIX}/{journal_entry_id}?next=%2F_next"
+        detail_uri: str = (f"{PREFIX}/{journal_entry_id}?"
+                           f"next={self.encoded_next_uri}")
         update_uri: str = f"{PREFIX}/{journal_entry_id}/update?as=disbursement"
         form_0: dict[str, str] = self.__get_update_form(journal_entry_id)
         form_0 = {x: form_0[x] for x in form_0 if "-credit-" not in x}
@@ -2035,7 +2066,8 @@ class TransferJournalEntryTestCase(unittest.TestCase):
         """
         journal_entry_id: int \
             = add_journal_entry(self.client, self.__get_add_form())
-        detail_uri: str = f"{PREFIX}/{journal_entry_id}?next=%2F_next"
+        detail_uri: str = (f"{PREFIX}/{journal_entry_id}?"
+                           f"next={self.encoded_next_uri}")
         delete_uri: str = f"{PREFIX}/{journal_entry_id}/delete"
         response: httpx.Response
 
@@ -2043,7 +2075,7 @@ class TransferJournalEntryTestCase(unittest.TestCase):
         self.assertEqual(response.status_code, 200)
         response = self.client.post(delete_uri,
                                     data={"csrf_token": self.csrf_token,
-                                          "next": NEXT_URI})
+                                          "next": self.encoded_next_uri})
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], NEXT_URI)
 
@@ -2051,7 +2083,7 @@ class TransferJournalEntryTestCase(unittest.TestCase):
         self.assertEqual(response.status_code, 404)
         response = self.client.post(delete_uri,
                                     data={"csrf_token": self.csrf_token,
-                                          "next": NEXT_URI})
+                                          "next": self.encoded_next_uri})
         self.assertEqual(response.status_code, 404)
 
     def __get_add_form(self) -> dict[str, str]:
@@ -2059,7 +2091,7 @@ class TransferJournalEntryTestCase(unittest.TestCase):
 
         :return: The form data to add a new journal entry.
         """
-        return get_add_form(self.csrf_token)
+        return get_add_form(self.csrf_token, self.encoded_next_uri)
 
     def __get_unchanged_update_form(self, journal_entry_id: int) \
             -> dict[str, str]:
@@ -2071,7 +2103,7 @@ class TransferJournalEntryTestCase(unittest.TestCase):
             not changed.
         """
         return get_unchanged_update_form(
-            journal_entry_id, self.app, self.csrf_token)
+            journal_entry_id, self.app, self.csrf_token, self.encoded_next_uri)
 
     def __get_update_form(self, journal_entry_id: int) -> dict[str, str]:
         """Returns the form data to update a journal entry, where the data are
@@ -2081,8 +2113,9 @@ class TransferJournalEntryTestCase(unittest.TestCase):
         :return: The form data to update the journal entry, where the data are
             changed.
         """
-        return get_update_form(journal_entry_id,
-                               self.app, self.csrf_token, None)
+        return get_update_form(
+            journal_entry_id, self.app, self.csrf_token, self.encoded_next_uri,
+            None)
 
 
 class JournalEntryReorderTestCase(unittest.TestCase):
@@ -2100,6 +2133,7 @@ class JournalEntryReorderTestCase(unittest.TestCase):
             from accounting.models import JournalEntry, JournalEntryLineItem
             JournalEntry.query.delete()
             JournalEntryLineItem.query.delete()
+            self.encoded_next_uri: str = encode_next(NEXT_URI)
 
         self.client, self.csrf_token = get_client(self.app, "editor")
 
@@ -2147,13 +2181,13 @@ class JournalEntryReorderTestCase(unittest.TestCase):
         response = self.client.post(f"{PREFIX}/{id_2}/update", data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"],
-                         f"{PREFIX}/{id_2}?next=%2F_next")
+                         f"{PREFIX}/{id_2}?next={self.encoded_next_uri}")
 
         with self.app.app_context():
             self.assertEqual(db.session.get(JournalEntry, id_1).no, 1)
             self.assertEqual(db.session.get(JournalEntry, id_2).no, 3)
             self.assertEqual(db.session.get(JournalEntry, id_3).no, 2)
-            self.assertEqual(   db.session.get(JournalEntry, id_4).no, 1)
+            self.assertEqual(db.session.get(JournalEntry, id_4).no, 1)
             self.assertEqual(db.session.get(JournalEntry, id_5).no, 2)
 
     def test_reorder(self) -> None:
@@ -2181,7 +2215,7 @@ class JournalEntryReorderTestCase(unittest.TestCase):
         response = self.client.post(
             f"{PREFIX}/dates/{date.isoformat()}",
             data={"csrf_token": self.csrf_token,
-                  "next": NEXT_URI,
+                  "next": self.encoded_next_uri,
                   f"{id_1}-no": "4",
                   f"{id_2}-no": "1",
                   f"{id_3}-no": "5",
@@ -2209,7 +2243,7 @@ class JournalEntryReorderTestCase(unittest.TestCase):
         response = self.client.post(
             f"{PREFIX}/dates/{date.isoformat()}",
             data={"csrf_token": self.csrf_token,
-                  "next": NEXT_URI,
+                  "next": self.encoded_next_uri,
                   f"{id_2}-no": "3a",
                   f"{id_3}-no": "5",
                   f"{id_4}-no": "2"})
@@ -2228,7 +2262,8 @@ class JournalEntryReorderTestCase(unittest.TestCase):
 
         :return: The form data to add a new cash receipt journal entry.
         """
-        form: dict[str, str] = get_add_form(self.csrf_token)
+        form: dict[str, str] = get_add_form(self.csrf_token,
+                                            self.encoded_next_uri)
         form = {x: form[x] for x in form if "-debit-" not in x}
         return form
 
@@ -2237,7 +2272,8 @@ class JournalEntryReorderTestCase(unittest.TestCase):
 
         :return: The form data to add a new cash disbursement journal entry.
         """
-        form: dict[str, str] = get_add_form(self.csrf_token)
+        form: dict[str, str] = get_add_form(self.csrf_token,
+                                            self.encoded_next_uri)
         form = {x: form[x] for x in form if "-credit-" not in x}
         return form
 
@@ -2251,7 +2287,7 @@ class JournalEntryReorderTestCase(unittest.TestCase):
             where the data are not changed.
         """
         form: dict[str, str] = get_unchanged_update_form(
-            journal_entry_id, self.app, self.csrf_token)
+            journal_entry_id, self.app, self.csrf_token, self.encoded_next_uri)
         form = {x: form[x] for x in form if "-credit-" not in x}
         return form
 
@@ -2260,4 +2296,4 @@ class JournalEntryReorderTestCase(unittest.TestCase):
 
         :return: The form data to add a new journal entry.
         """
-        return get_add_form(self.csrf_token)
+        return get_add_form(self.csrf_token, self.encoded_next_uri)

tests/test_offset.py

@@ -25,6 +25,7 @@ from decimal import Decimal
 import httpx
 from flask import Flask
 
+from accounting.utils.next_uri import encode_next
 from test_site import db
 from test_site.lib import JournalEntryLineItemData, JournalEntryCurrencyData, \
     JournalEntryData, BaseTestData
@@ -50,6 +51,7 @@ class OffsetTestCase(unittest.TestCase):
             from accounting.models import JournalEntry, JournalEntryLineItem
             JournalEntry.query.delete()
             JournalEntryLineItem.query.delete()
+            self.encoded_next_uri: str = encode_next(NEXT_URI)
 
         self.client, self.csrf_token = get_client(self.app, "editor")
         self.data: OffsetTestData = OffsetTestData(self.app, "editor")
@@ -61,7 +63,8 @@ class OffsetTestCase(unittest.TestCase):
         :return: None.
         """
         from accounting.models import Account, JournalEntry
-        create_uri: str = f"{PREFIX}/create/receipt?next=%2F_next"
+        create_uri: str = (f"{PREFIX}/create/receipt?"
+                           f"next={self.encoded_next_uri}")
         store_uri: str = f"{PREFIX}/store/receipt"
         form: dict[str, str]
         old_amount: Decimal
@@ -85,14 +88,16 @@ class OffsetTestCase(unittest.TestCase):
                      original_line_item=self.data.l_r_or3d)])])
 
         # Non-existing original line item ID
-        form = journal_entry_data.new_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.new_form(self.csrf_token,
+                                           self.encoded_next_uri)
         form["currency-1-credit-1-original_line_item_id"] = "9999"
         response = self.client.post(store_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], create_uri)
 
         # The same debit or credit
-        form = journal_entry_data.new_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.new_form(self.csrf_token,
+                                           self.encoded_next_uri)
         form["currency-1-credit-1-original_line_item_id"] \
             = str(self.data.l_p_or1c.id)
         form["currency-1-credit-1-account_code"] = self.data.l_p_or1c.account
@@ -108,7 +113,8 @@ class OffsetTestCase(unittest.TestCase):
             db.session.commit()
         response = self.client.post(
             store_uri,
-            data=journal_entry_data.new_form(self.csrf_token, NEXT_URI))
+            data=journal_entry_data.new_form(self.csrf_token,
+                                             self.encoded_next_uri))
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], create_uri)
         with self.app.app_context():
@@ -117,7 +123,8 @@ class OffsetTestCase(unittest.TestCase):
             db.session.commit()
 
         # The original line item is also an offset
-        form = journal_entry_data.new_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.new_form(self.csrf_token,
+                                           self.encoded_next_uri)
         form["currency-1-credit-1-original_line_item_id"] \
             = str(self.data.l_p_of1d.id)
         form["currency-1-credit-1-account_code"] = self.data.l_p_of1d.account
@@ -126,21 +133,24 @@ class OffsetTestCase(unittest.TestCase):
         self.assertEqual(response.headers["Location"], create_uri)
 
         # Not the same currency
-        form = journal_entry_data.new_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.new_form(self.csrf_token,
+                                           self.encoded_next_uri)
         form["currency-1-code"] = "EUR"
         response = self.client.post(store_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], create_uri)
 
         # Not the same account
-        form = journal_entry_data.new_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.new_form(self.csrf_token,
+                                           self.encoded_next_uri)
         form["currency-1-credit-1-account_code"] = Accounts.NOTES_RECEIVABLE
         response = self.client.post(store_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], create_uri)
 
         # Not exceeding net balance - partially offset
-        form = journal_entry_data.new_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.new_form(self.csrf_token,
+                                           self.encoded_next_uri)
         form["currency-1-credit-1-amount"] \
             = str(journal_entry_data.currencies[0].credit[0].amount
                   + Decimal("0.01"))
@@ -149,7 +159,8 @@ class OffsetTestCase(unittest.TestCase):
         self.assertEqual(response.headers["Location"], create_uri)
 
         # Not exceeding net balance - unmatched
-        form = journal_entry_data.new_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.new_form(self.csrf_token,
+                                           self.encoded_next_uri)
         form["currency-1-credit-3-amount"] \
             = str(journal_entry_data.currencies[0].credit[2].amount
                   + Decimal("0.01"))
@@ -160,14 +171,16 @@ class OffsetTestCase(unittest.TestCase):
         # Not before the original line items
         old_days = journal_entry_data.days
         journal_entry_data.days = old_days + 1
-        form = journal_entry_data.new_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.new_form(self.csrf_token,
+                                           self.encoded_next_uri)
         response = self.client.post(store_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], create_uri)
         journal_entry_data.days = old_days
 
         # Success
-        form = journal_entry_data.new_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.new_form(self.csrf_token,
+                                           self.encoded_next_uri)
         response = self.client.post(store_uri, data=form)
         self.assertEqual(response.status_code, 302)
         journal_entry_id: int \
@@ -184,7 +197,8 @@ class OffsetTestCase(unittest.TestCase):
         """
         from accounting.models import Account
         journal_entry_data: JournalEntryData = self.data.j_r_of2
-        edit_uri: str = f"{PREFIX}/{journal_entry_data.id}/edit?next=%2F_next"
+        edit_uri: str = (f"{PREFIX}/{journal_entry_data.id}/edit?"
+                         f"next={self.encoded_next_uri}")
         update_uri: str = f"{PREFIX}/{journal_entry_data.id}/update"
         form: dict[str, str]
         response: httpx.Response
@@ -196,14 +210,16 @@ class OffsetTestCase(unittest.TestCase):
         journal_entry_data.currencies[0].credit[2].amount = Decimal("600")
 
         # Non-existing original line item ID
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-credit-1-original_line_item_id"] = "9999"
         response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], edit_uri)
 
         # The same debit or credit
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-credit-1-original_line_item_id"] \
             = str(self.data.l_p_or1c.id)
         form["currency-1-credit-1-account_code"] = self.data.l_p_or1c.account
@@ -220,7 +236,8 @@ class OffsetTestCase(unittest.TestCase):
             db.session.commit()
         response = self.client.post(
             update_uri,
-            data=journal_entry_data.update_form(self.csrf_token, NEXT_URI))
+            data=journal_entry_data.update_form(self.csrf_token,
+                                                self.encoded_next_uri))
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], edit_uri)
         with self.app.app_context():
@@ -229,7 +246,8 @@ class OffsetTestCase(unittest.TestCase):
             db.session.commit()
 
         # The original line item is also an offset
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-credit-1-original_line_item_id"] \
             = str(self.data.l_p_of1d.id)
         form["currency-1-credit-1-account_code"] = self.data.l_p_of1d.account
@@ -238,21 +256,24 @@ class OffsetTestCase(unittest.TestCase):
         self.assertEqual(response.headers["Location"], edit_uri)
 
         # Not the same currency
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-code"] = "EUR"
         response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], edit_uri)
 
         # Not the same account
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-credit-1-account_code"] = Accounts.NOTES_RECEIVABLE
         response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], edit_uri)
 
         # Not exceeding net balance - partially offset
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-debit-1-amount"] \
             = str(journal_entry_data.currencies[0].debit[0].amount
                   + Decimal("0.01"))
@@ -264,7 +285,8 @@ class OffsetTestCase(unittest.TestCase):
         self.assertEqual(response.headers["Location"], edit_uri)
 
         # Not exceeding net balance - unmatched
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-debit-3-amount"] \
             = str(journal_entry_data.currencies[0].debit[2].amount
                   + Decimal("0.01"))
@@ -278,18 +300,21 @@ class OffsetTestCase(unittest.TestCase):
         # Not before the original line items
         old_days: int = journal_entry_data.days
         journal_entry_data.days = old_days + 1
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], edit_uri)
         journal_entry_data.days = old_days
 
         # Success
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"],
-                         f"{PREFIX}/{journal_entry_data.id}?next=%2F_next")
+                         f"{PREFIX}/{journal_entry_data.id}?"
+                         f"next={self.encoded_next_uri}")
 
     def test_edit_receivable_original_line_item(self) -> None:
         """Tests to edit the receivable original line item.
@@ -298,7 +323,8 @@ class OffsetTestCase(unittest.TestCase):
         """
         from accounting.models import JournalEntry
         journal_entry_data: JournalEntryData = self.data.j_r_or1
-        edit_uri: str = f"{PREFIX}/{journal_entry_data.id}/edit?next=%2F_next"
+        edit_uri: str = (f"{PREFIX}/{journal_entry_data.id}/edit?"
+                         f"next={self.encoded_next_uri}")
         update_uri: str = f"{PREFIX}/{journal_entry_data.id}/update"
         form: dict[str, str]
         response: httpx.Response
@@ -310,21 +336,24 @@ class OffsetTestCase(unittest.TestCase):
         journal_entry_data.currencies[0].credit[1].amount = Decimal("3.4")
 
         # Not the same currency
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-code"] = "EUR"
         response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], edit_uri)
 
         # Not the same account
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-debit-1-account_code"] = Accounts.NOTES_RECEIVABLE
         response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], edit_uri)
 
         # Not less than offset total - partially offset
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-debit-1-amount"] \
             = str(journal_entry_data.currencies[0].debit[0].amount
                   - Decimal("0.01"))
@@ -336,7 +365,8 @@ class OffsetTestCase(unittest.TestCase):
         self.assertEqual(response.headers["Location"], edit_uri)
 
         # Not less than offset total - fully offset
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-debit-2-amount"] \
             = str(journal_entry_data.currencies[0].debit[1].amount
                   - Decimal("0.01"))
@@ -350,25 +380,29 @@ class OffsetTestCase(unittest.TestCase):
         # Not after the offset items
         old_days: int = journal_entry_data.days
         journal_entry_data.days = old_days - 1
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], edit_uri)
         journal_entry_data.days = old_days
 
         # Not deleting matched original line items
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         del form["currency-1-debit-1-id"]
         response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], edit_uri)
 
         # Success
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"],
-                         f"{PREFIX}/{journal_entry_data.id}?next=%2F_next")
+                         f"{PREFIX}/{journal_entry_data.id}?"
+                         f"next={self.encoded_next_uri}")
 
         # The original line item is always before the offset item, even when
         # they happen in the same day.
@@ -388,7 +422,8 @@ class OffsetTestCase(unittest.TestCase):
         :return: None.
         """
         from accounting.models import Account, JournalEntry
-        create_uri: str = f"{PREFIX}/create/disbursement?next=%2F_next"
+        create_uri: str = (f"{PREFIX}/create/disbursement?"
+                           f"next={self.encoded_next_uri}")
         store_uri: str = f"{PREFIX}/store/disbursement"
         form: dict[str, str]
         response: httpx.Response
@@ -411,14 +446,16 @@ class OffsetTestCase(unittest.TestCase):
                 [])])
 
         # Non-existing original line item ID
-        form = journal_entry_data.new_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.new_form(self.csrf_token,
+                                           self.encoded_next_uri)
         form["currency-1-debit-1-original_line_item_id"] = "9999"
         response = self.client.post(store_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], create_uri)
 
         # The same debit or credit
-        form = journal_entry_data.new_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.new_form(self.csrf_token,
+                                           self.encoded_next_uri)
         form["currency-1-debit-1-original_line_item_id"] \
             = str(self.data.l_r_or1d.id)
         form["currency-1-debit-1-account_code"] = self.data.l_r_or1d.account
@@ -434,7 +471,8 @@ class OffsetTestCase(unittest.TestCase):
             db.session.commit()
         response = self.client.post(
             store_uri,
-            data=journal_entry_data.new_form(self.csrf_token, NEXT_URI))
+            data=journal_entry_data.new_form(self.csrf_token,
+                                             self.encoded_next_uri))
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], create_uri)
         with self.app.app_context():
@@ -443,7 +481,8 @@ class OffsetTestCase(unittest.TestCase):
             db.session.commit()
 
         # The original line item is also an offset
-        form = journal_entry_data.new_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.new_form(self.csrf_token,
+                                           self.encoded_next_uri)
         form["currency-1-debit-1-original_line_item_id"] \
             = str(self.data.l_r_of1c.id)
         form["currency-1-debit-1-account_code"] = self.data.l_r_of1c.account
@@ -452,21 +491,24 @@ class OffsetTestCase(unittest.TestCase):
         self.assertEqual(response.headers["Location"], create_uri)
 
         # Not the same currency
-        form = journal_entry_data.new_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.new_form(self.csrf_token,
+                                           self.encoded_next_uri)
         form["currency-1-code"] = "EUR"
         response = self.client.post(store_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], create_uri)
 
         # Not the same account
-        form = journal_entry_data.new_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.new_form(self.csrf_token,
+                                           self.encoded_next_uri)
         form["currency-1-debit-1-account_code"] = Accounts.NOTES_PAYABLE
         response = self.client.post(store_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], create_uri)
 
         # Not exceeding net balance - partially offset
-        form = journal_entry_data.new_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.new_form(self.csrf_token,
+                                           self.encoded_next_uri)
         form["currency-1-debit-1-amount"] \
             = str(journal_entry_data.currencies[0].debit[0].amount
                   + Decimal("0.01"))
@@ -475,7 +517,8 @@ class OffsetTestCase(unittest.TestCase):
         self.assertEqual(response.headers["Location"], create_uri)
 
         # Not exceeding net balance - unmatched
-        form = journal_entry_data.new_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.new_form(self.csrf_token,
+                                           self.encoded_next_uri)
         form["currency-1-debit-3-amount"] \
             = str(journal_entry_data.currencies[0].debit[2].amount
                   + Decimal("0.01"))
@@ -486,14 +529,16 @@ class OffsetTestCase(unittest.TestCase):
         # Not before the original line items
         old_days: int = journal_entry_data.days
         journal_entry_data.days = old_days + 1
-        form = journal_entry_data.new_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.new_form(self.csrf_token,
+                                           self.encoded_next_uri)
         response = self.client.post(store_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], create_uri)
         journal_entry_data.days = old_days
 
         # Success
-        form = journal_entry_data.new_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.new_form(self.csrf_token,
+                                           self.encoded_next_uri)
         response = self.client.post(store_uri, data=form)
         self.assertEqual(response.status_code, 302)
         journal_entry_id: int \
@@ -510,7 +555,8 @@ class OffsetTestCase(unittest.TestCase):
         """
         from accounting.models import Account, JournalEntry
         journal_entry_data: JournalEntryData = self.data.j_p_of2
-        edit_uri: str = f"{PREFIX}/{journal_entry_data.id}/edit?next=%2F_next"
+        edit_uri: str = (f"{PREFIX}/{journal_entry_data.id}/edit?"
+                         f"next={self.encoded_next_uri}")
         update_uri: str = f"{PREFIX}/{journal_entry_data.id}/update"
         form: dict[str, str]
         response: httpx.Response
@@ -522,14 +568,16 @@ class OffsetTestCase(unittest.TestCase):
         journal_entry_data.currencies[0].credit[2].amount = Decimal("900")
 
         # Non-existing original line item ID
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-debit-1-original_line_item_id"] = "9999"
         response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], edit_uri)
 
         # The same debit or credit
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-debit-1-original_line_item_id"] \
             = str(self.data.l_r_or1d.id)
         form["currency-1-debit-1-account_code"] = self.data.l_r_or1d.account
@@ -546,7 +594,8 @@ class OffsetTestCase(unittest.TestCase):
             db.session.commit()
         response = self.client.post(
             update_uri,
-            data=journal_entry_data.update_form(self.csrf_token, NEXT_URI))
+            data=journal_entry_data.update_form(self.csrf_token,
+                                                self.encoded_next_uri))
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], edit_uri)
         with self.app.app_context():
@@ -555,7 +604,8 @@ class OffsetTestCase(unittest.TestCase):
             db.session.commit()
 
         # The original line item is also an offset
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-debit-1-original_line_item_id"] \
             = str(self.data.l_r_of1c.id)
         form["currency-1-debit-1-account_code"] = self.data.l_r_of1c.account
@@ -564,21 +614,24 @@ class OffsetTestCase(unittest.TestCase):
         self.assertEqual(response.headers["Location"], edit_uri)
 
         # Not the same currency
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-code"] = "EUR"
         response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], edit_uri)
 
         # Not the same account
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-debit-1-account_code"] = Accounts.NOTES_PAYABLE
         response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], edit_uri)
 
         # Not exceeding net balance - partially offset
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-debit-1-amount"] \
             = str(journal_entry_data.currencies[0].debit[0].amount
                   + Decimal("0.01"))
@@ -590,7 +643,8 @@ class OffsetTestCase(unittest.TestCase):
         self.assertEqual(response.headers["Location"], edit_uri)
 
         # Not exceeding net balance - unmatched
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-debit-3-amount"] \
             = str(journal_entry_data.currencies[0].debit[2].amount
                   + Decimal("0.01"))
@@ -604,14 +658,16 @@ class OffsetTestCase(unittest.TestCase):
         # Not before the original line items
         old_days: int = journal_entry_data.days
         journal_entry_data.days = old_days + 1
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], edit_uri)
         journal_entry_data.days = old_days
 
         # Success
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
         journal_entry_id: int \
@@ -628,7 +684,8 @@ class OffsetTestCase(unittest.TestCase):
         """
         from accounting.models import JournalEntry
         journal_entry_data: JournalEntryData = self.data.j_p_or1
-        edit_uri: str = f"{PREFIX}/{journal_entry_data.id}/edit?next=%2F_next"
+        edit_uri: str = (f"{PREFIX}/{journal_entry_data.id}/edit?"
+                         f"next={self.encoded_next_uri}")
         update_uri: str = f"{PREFIX}/{journal_entry_data.id}/update"
         form: dict[str, str]
         response: httpx.Response
@@ -640,21 +697,24 @@ class OffsetTestCase(unittest.TestCase):
         journal_entry_data.currencies[0].credit[1].amount = Decimal("0.9")
 
         # Not the same currency
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-code"] = "EUR"
         response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], edit_uri)
 
         # Not the same account
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-credit-1-account_code"] = Accounts.NOTES_PAYABLE
         response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], edit_uri)
 
         # Not less than offset total - partially offset
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-debit-1-amount"] \
             = str(journal_entry_data.currencies[0].debit[0].amount
                   - Decimal("0.01"))
@@ -666,7 +726,8 @@ class OffsetTestCase(unittest.TestCase):
         self.assertEqual(response.headers["Location"], edit_uri)
 
         # Not less than offset total - fully offset
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         form["currency-1-debit-2-amount"] \
             = str(journal_entry_data.currencies[0].debit[1].amount
                   - Decimal("0.01"))
@@ -680,25 +741,29 @@ class OffsetTestCase(unittest.TestCase):
         # Not after the offset items
         old_days: int = journal_entry_data.days
         journal_entry_data.days = old_days - 1
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], edit_uri)
         journal_entry_data.days = old_days
 
         # Not deleting matched original line items
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         del form["currency-1-credit-1-id"]
         response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], edit_uri)
 
         # Success
-        form = journal_entry_data.update_form(self.csrf_token, NEXT_URI)
+        form = journal_entry_data.update_form(self.csrf_token,
+                                              self.encoded_next_uri)
         response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"],
-                         f"{PREFIX}/{journal_entry_data.id}?next=%2F_next")
+                         f"{PREFIX}/{journal_entry_data.id}?"
+                         f"next={self.encoded_next_uri}")
 
         # The original line item is always before the offset item, even when
         # they happen in the same day

tests/test_option.py

@@ -23,17 +23,12 @@ import unittest
 import httpx
 from flask import Flask
 
+from accounting.utils.next_uri import encode_next
 from test_site import db
 from testlib import NEXT_URI, Accounts, create_test_app, get_client
 
 PREFIX: str = "/accounting/options"
 """The URL prefix for the option management."""
-DETAIL_URI: str = f"{PREFIX}?next=%2F_next"
-"""THE URI for the option detail."""
-EDIT_URI: str = f"{PREFIX}/edit?next=%2F_next"
-"""THE URI for the form to edit the options."""
-UPDATE_URI: str = f"{PREFIX}/update"
-"""THE URI to update the options."""
 
 
 class OptionTestCase(unittest.TestCase):
@@ -50,6 +45,7 @@ class OptionTestCase(unittest.TestCase):
         with self.app.app_context():
             from accounting.models import Option
             Option.query.delete()
+            self.encoded_next_uri: str = encode_next(NEXT_URI)
 
         self.client, self.csrf_token = get_client(self.app, "admin")
 
@@ -59,15 +55,18 @@ class OptionTestCase(unittest.TestCase):
         :return: None.
         """
         client, csrf_token = get_client(self.app, "nobody")
+        detail_uri: str = f"{PREFIX}?next={self.encoded_next_uri}"
+        edit_uri: str = f"{PREFIX}/edit?next={self.encoded_next_uri}"
+        update_uri: str = f"{PREFIX}/update"
         response: httpx.Response
 
-        response = client.get(DETAIL_URI)
+        response = client.get(detail_uri)
         self.assertEqual(response.status_code, 403)
 
-        response = client.get(EDIT_URI)
+        response = client.get(edit_uri)
         self.assertEqual(response.status_code, 403)
 
-        response = client.post(UPDATE_URI, data=self.__get_form(csrf_token))
+        response = client.post(update_uri, data=self.__get_form(csrf_token))
         self.assertEqual(response.status_code, 403)
 
     def test_viewer(self) -> None:
@@ -76,15 +75,18 @@ class OptionTestCase(unittest.TestCase):
         :return: None.
         """
         client, csrf_token = get_client(self.app, "viewer")
+        detail_uri: str = f"{PREFIX}?next={self.encoded_next_uri}"
+        edit_uri: str = f"{PREFIX}/edit?next={self.encoded_next_uri}"
+        update_uri: str = f"{PREFIX}/update"
         response: httpx.Response
 
-        response = client.get(DETAIL_URI)
+        response = client.get(detail_uri)
         self.assertEqual(response.status_code, 403)
 
-        response = client.get(EDIT_URI)
+        response = client.get(edit_uri)
         self.assertEqual(response.status_code, 403)
 
-        response = client.post(UPDATE_URI, data=self.__get_form(csrf_token))
+        response = client.post(update_uri, data=self.__get_form(csrf_token))
         self.assertEqual(response.status_code, 403)
 
     def test_editor(self) -> None:
@@ -93,15 +95,18 @@ class OptionTestCase(unittest.TestCase):
         :return: None.
         """
         client, csrf_token = get_client(self.app, "editor")
+        detail_uri: str = f"{PREFIX}?next={self.encoded_next_uri}"
+        edit_uri: str = f"{PREFIX}/edit?next={self.encoded_next_uri}"
+        update_uri: str = f"{PREFIX}/update"
         response: httpx.Response
 
-        response = client.get(DETAIL_URI)
+        response = client.get(detail_uri)
         self.assertEqual(response.status_code, 403)
 
-        response = client.get(EDIT_URI)
+        response = client.get(edit_uri)
         self.assertEqual(response.status_code, 403)
 
-        response = client.post(UPDATE_URI, data=self.__get_form(csrf_token))
+        response = client.post(update_uri, data=self.__get_form(csrf_token))
         self.assertEqual(response.status_code, 403)
 
     def test_admin(self) -> None:
@@ -109,17 +114,20 @@ class OptionTestCase(unittest.TestCase):
 
         :return: None.
         """
+        detail_uri: str = f"{PREFIX}?next={self.encoded_next_uri}"
+        edit_uri: str = f"{PREFIX}/edit?next={self.encoded_next_uri}"
+        update_uri: str = f"{PREFIX}/update"
         response: httpx.Response
 
-        response = self.client.get(DETAIL_URI)
+        response = self.client.get(detail_uri)
         self.assertEqual(response.status_code, 200)
 
-        response = self.client.get(EDIT_URI)
+        response = self.client.get(edit_uri)
         self.assertEqual(response.status_code, 200)
 
-        response = self.client.post(UPDATE_URI, data=self.__get_form())
+        response = self.client.post(update_uri, data=self.__get_form())
         self.assertEqual(response.status_code, 302)
-        self.assertEqual(response.headers["Location"], DETAIL_URI)
+        self.assertEqual(response.headers["Location"], detail_uri)
 
     def test_set(self) -> None:
         """Test to set the options.
@@ -127,59 +135,62 @@ class OptionTestCase(unittest.TestCase):
         :return: None.
         """
         from accounting.utils.options import options
+        detail_uri: str = f"{PREFIX}?next={self.encoded_next_uri}"
+        edit_uri: str = f"{PREFIX}/edit?next={self.encoded_next_uri}"
+        update_uri: str = f"{PREFIX}/update"
         form: dict[str, str]
         response: httpx.Response
 
         # Empty currency code
         form = self.__get_form()
         form["default_currency_code"] = " "
-        response = self.client.post(UPDATE_URI, data=form)
+        response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
-        self.assertEqual(response.headers["Location"], EDIT_URI)
+        self.assertEqual(response.headers["Location"], edit_uri)
 
         # Non-existing currency code
         form = self.__get_form()
         form["default_currency_code"] = "ZZZ"
-        response = self.client.post(UPDATE_URI, data=form)
+        response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
-        self.assertEqual(response.headers["Location"], EDIT_URI)
+        self.assertEqual(response.headers["Location"], edit_uri)
 
         # Empty current account
         form = self.__get_form()
         form["default_ie_account_code"] = " "
-        response = self.client.post(UPDATE_URI, data=form)
+        response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
-        self.assertEqual(response.headers["Location"], EDIT_URI)
+        self.assertEqual(response.headers["Location"], edit_uri)
 
         # Non-existing current account
         form = self.__get_form()
         form["default_ie_account_code"] = "9999-999"
-        response = self.client.post(UPDATE_URI, data=form)
+        response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
-        self.assertEqual(response.headers["Location"], EDIT_URI)
+        self.assertEqual(response.headers["Location"], edit_uri)
 
         # Not a current account
         form = self.__get_form()
         form["default_ie_account_code"] = Accounts.MEAL
-        response = self.client.post(UPDATE_URI, data=form)
+        response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
-        self.assertEqual(response.headers["Location"], EDIT_URI)
+        self.assertEqual(response.headers["Location"], edit_uri)
 
         # Recurring item name empty
         form = self.__get_form()
         key = [x for x in form if x.endswith("-name")][0]
         form[key] = " "
-        response = self.client.post(UPDATE_URI, data=form)
+        response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
-        self.assertEqual(response.headers["Location"], EDIT_URI)
+        self.assertEqual(response.headers["Location"], edit_uri)
 
         # Recurring item account empty
         form = self.__get_form()
         key = [x for x in form if x.endswith("-account_code")][0]
         form[key] = " "
-        response = self.client.post(UPDATE_URI, data=form)
+        response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
-        self.assertEqual(response.headers["Location"], EDIT_URI)
+        self.assertEqual(response.headers["Location"], edit_uri)
 
         # Recurring item non-expense account
         form = self.__get_form()
@@ -187,9 +198,9 @@ class OptionTestCase(unittest.TestCase):
                if x.startswith("recurring-expense-")
                and x.endswith("-account_code")][0]
         form[key] = Accounts.SERVICE
-        response = self.client.post(UPDATE_URI, data=form)
+        response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
-        self.assertEqual(response.headers["Location"], EDIT_URI)
+        self.assertEqual(response.headers["Location"], edit_uri)
 
         # Recurring item non-income account
         form = self.__get_form()
@@ -197,9 +208,9 @@ class OptionTestCase(unittest.TestCase):
                if x.startswith("recurring-income-")
                and x.endswith("-account_code")][0]
         form[key] = Accounts.UTILITIES
-        response = self.client.post(UPDATE_URI, data=form)
+        response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
-        self.assertEqual(response.headers["Location"], EDIT_URI)
+        self.assertEqual(response.headers["Location"], edit_uri)
 
         # Recurring item payable expense
         form = self.__get_form()
@@ -207,9 +218,9 @@ class OptionTestCase(unittest.TestCase):
                if x.startswith("recurring-expense-")
                and x.endswith("-account_code")][0]
         form[key] = Accounts.PAYABLE
-        response = self.client.post(UPDATE_URI, data=form)
+        response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
-        self.assertEqual(response.headers["Location"], EDIT_URI)
+        self.assertEqual(response.headers["Location"], edit_uri)
 
         # Recurring item receivable income
         form = self.__get_form()
@@ -217,17 +228,17 @@ class OptionTestCase(unittest.TestCase):
                if x.startswith("recurring-income-")
                and x.endswith("-account_code")][0]
         form[key] = Accounts.RECEIVABLE
-        response = self.client.post(UPDATE_URI, data=form)
+        response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
-        self.assertEqual(response.headers["Location"], EDIT_URI)
+        self.assertEqual(response.headers["Location"], edit_uri)
 
         # Recurring item description template empty
         form = self.__get_form()
         key = [x for x in form if x.endswith("-description_template")][0]
         form[key] = " "
-        response = self.client.post(UPDATE_URI, data=form)
+        response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
-        self.assertEqual(response.headers["Location"], EDIT_URI)
+        self.assertEqual(response.headers["Location"], edit_uri)
 
         # Success, with malformed order
         with self.app.app_context():
@@ -236,9 +247,9 @@ class OptionTestCase(unittest.TestCase):
             self.assertEqual(len(options.recurring.expenses), 0)
             self.assertEqual(len(options.recurring.incomes), 0)
 
-        response = self.client.post(UPDATE_URI, data=self.__get_form())
+        response = self.client.post(update_uri, data=self.__get_form())
         self.assertEqual(response.status_code, 302)
-        self.assertEqual(response.headers["Location"], DETAIL_URI)
+        self.assertEqual(response.headers["Location"], detail_uri)
 
         with self.app.app_context():
             self.assertEqual(options.default_currency_code, "EUR")
@@ -261,9 +272,9 @@ class OptionTestCase(unittest.TestCase):
         # Success, with no recurring data
         form = self.__get_form()
         form = {x: form[x] for x in form if not x.startswith("recurring-")}
-        response = self.client.post(UPDATE_URI, data=form)
+        response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
-        self.assertEqual(response.headers["Location"], DETAIL_URI)
+        self.assertEqual(response.headers["Location"], detail_uri)
 
         with self.app.app_context():
             self.assertEqual(len(options.recurring.expenses), 0)
@@ -275,13 +286,15 @@ class OptionTestCase(unittest.TestCase):
         :return: None.
         """
         from accounting.models import Option
+        detail_uri: str = f"{PREFIX}?next={self.encoded_next_uri}"
+        update_uri: str = f"{PREFIX}/update"
         form: dict[str, str]
         option: Option | None
         resource: httpx.Response
 
-        response = self.client.post(UPDATE_URI, data=self.__get_form())
+        response = self.client.post(update_uri, data=self.__get_form())
         self.assertEqual(response.status_code, 302)
-        self.assertEqual(response.headers["Location"], DETAIL_URI)
+        self.assertEqual(response.headers["Location"], detail_uri)
 
         with self.app.app_context():
             option = db.session.get(Option, "recurring")
@@ -295,9 +308,9 @@ class OptionTestCase(unittest.TestCase):
         # The recurring setting was not modified
         form = self.__get_form()
         form["default_currency_code"] = "JPY"
-        response = self.client.post(UPDATE_URI, data=form)
+        response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
-        self.assertEqual(response.headers["Location"], DETAIL_URI)
+        self.assertEqual(response.headers["Location"], detail_uri)
 
         with self.app.app_context():
             option = db.session.get(Option, "recurring")
@@ -311,9 +324,9 @@ class OptionTestCase(unittest.TestCase):
                     if x.startswith("recurring-expense-")
                     and x.endswith("-account_code")][0]
         form[key] = Accounts.MEAL
-        response = self.client.post(UPDATE_URI, data=form)
+        response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
-        self.assertEqual(response.headers["Location"], DETAIL_URI)
+        self.assertEqual(response.headers["Location"], detail_uri)
 
         with self.app.app_context():
             option = db.session.get(Option, "recurring")
@@ -328,12 +341,14 @@ class OptionTestCase(unittest.TestCase):
         from accounting.models import Option
         from accounting.utils.user import get_user_pk
         admin_username, editor_username = "admin", "editor"
+        detail_uri: str = f"{PREFIX}?next={self.encoded_next_uri}"
+        update_uri: str = f"{PREFIX}/update"
         option: Option | None
         response: httpx.Response
 
-        response = self.client.post(UPDATE_URI, data=self.__get_form())
+        response = self.client.post(update_uri, data=self.__get_form())
         self.assertEqual(response.status_code, 302)
-        self.assertEqual(response.headers["Location"], DETAIL_URI)
+        self.assertEqual(response.headers["Location"], detail_uri)
 
         with self.app.app_context():
             editor_pk: int = get_user_pk(editor_username)
@@ -348,9 +363,9 @@ class OptionTestCase(unittest.TestCase):
                     if x.startswith("recurring-expense-")
                     and x.endswith("-account_code")][0]
         form[key] = Accounts.MEAL
-        response = self.client.post(UPDATE_URI, data=form)
+        response = self.client.post(update_uri, data=form)
         self.assertEqual(response.status_code, 302)
-        self.assertEqual(response.headers["Location"], DETAIL_URI)
+        self.assertEqual(response.headers["Location"], detail_uri)
 
         with self.app.app_context():
             option = db.session.get(Option, "recurring")
@@ -367,7 +382,7 @@ class OptionTestCase(unittest.TestCase):
         if csrf_token is None:
             csrf_token = self.csrf_token
         return {"csrf_token": csrf_token,
-                "next": NEXT_URI,
+                "next": self.encoded_next_uri,
                 "default_currency_code": "EUR",
                 "default_ie_account_code": "0000-000",
                 "recurring-expense-1-name": "Water bill",

tests/test_site/__init__.py

@@ -23,13 +23,15 @@ from typing import Type
 
 from click.testing import Result
 from flask import Flask, Blueprint, render_template, redirect, Response, \
-    url_for
+    url_for, request
 from flask.testing import FlaskCliRunner
 from flask_babel_js import BabelJS
 from flask_sqlalchemy import SQLAlchemy
 from flask_wtf import CSRFProtect
 from sqlalchemy import Column
 
+from accounting.utils.next_uri import encode_next
+
 bp: Blueprint = Blueprint("home", __name__)
 """The global blueprint."""
 babel_js: BabelJS = BabelJS()
@@ -66,6 +68,7 @@ def create_app(is_testing: bool = False) -> Flask:
     db.init_app(app)
 
     app.register_blueprint(bp, url_prefix="/")
+    app.add_template_global(__as_next, "accounting_as_next")
 
     from . import locale
     locale.init_app(app)
@@ -146,3 +149,12 @@ def get_home() -> str:
     :return: The home page.
     """
     return render_template("home.html")
+
+
+def __as_next() -> str:
+    """Encodes the current request URI as value for the next URI.
+
+    :return: The current request URI as value for the next URI.
+    """
+    return encode_next(
+        request.full_path if request.query_string else request.path)

tests/test_site/lib.py

@@ -140,36 +140,38 @@ class JournalEntryData:
             for line_item in currency.credit:
                 line_item.journal_entry = self
 
-    def new_form(self, csrf_token: str, next_uri: str) -> dict[str, str]:
+    def new_form(self, csrf_token: str, encoded_next_uri: str) \
+            -> dict[str, str]:
         """Returns the journal entry as a creation form.
 
         :param csrf_token: The CSRF token.
-        :param next_uri: The next URI.
+        :param encoded_next_uri: The encoded next URI.
         :return: The journal entry as a creation form.
         """
-        return self.__form(csrf_token, next_uri, is_update=False)
+        return self.__form(csrf_token, encoded_next_uri, is_update=False)
 
-    def update_form(self, csrf_token: str, next_uri: str) -> dict[str, str]:
+    def update_form(self, csrf_token: str, encoded_next_uri: str) \
+            -> dict[str, str]:
         """Returns the journal entry as an update form.
 
         :param csrf_token: The CSRF token.
-        :param next_uri: The next URI.
+        :param encoded_next_uri: The encoded next URI.
         :return: The journal entry as an update form.
         """
-        return self.__form(csrf_token, next_uri, is_update=True)
+        return self.__form(csrf_token, encoded_next_uri, is_update=True)
 
-    def __form(self, csrf_token: str, next_uri: str, is_update: bool = False) \
-            -> dict[str, str]:
+    def __form(self, csrf_token: str, encoded_next_uri: str,
+               is_update: bool = False) -> dict[str, str]:
         """Returns the journal entry as a form.
 
         :param csrf_token: The CSRF token.
-        :param next_uri: The next URI.
+        :param encoded_next_uri: The encoded next URI.
         :param is_update: True for an update operation, or False otherwise
         :return: The journal entry as a form.
         """
         date: dt.date = dt.date.today() - dt.timedelta(days=self.days)
         form: dict[str, str] = {"csrf_token": csrf_token,
-                                "next": next_uri,
+                                "next": encoded_next_uri,
                                 "date": date.isoformat()}
         for i in range(len(self.currencies)):
             form.update(self.currencies[i].form(i + 1, is_update))

tests/test_site/templates/base.html

@@ -96,7 +96,7 @@ First written: 2023/1/27
           </span>
           <form action="{{ url_for("locale.set-locale") }}" method="post">
             <input type="hidden" name="csrf_token" value="{{ csrf_token() }}">
-            <input type="hidden" name="next" value="{{ request.full_path if request.query_string else request.path }}">
+            <input type="hidden" name="next" value="{{ accounting_as_next() }}">
             <ul class="dropdown-menu dropdown-menu-end">
               {% for locale_code, locale_name in get_all_linguas().items() %}
                 <li>

tests/test_unmatched_offset.py

@@ -22,6 +22,7 @@ import unittest
 import httpx
 from flask import Flask
 
+from accounting.utils.next_uri import encode_next
 from test_site import db
 from test_site.lib import JournalEntryCurrencyData, JournalEntryData, \
     BaseTestData
@@ -46,6 +47,7 @@ class UnmatchedOffsetTestCase(unittest.TestCase):
             from accounting.models import JournalEntry, JournalEntryLineItem
             JournalEntry.query.delete()
             JournalEntryLineItem.query.delete()
+            self.encoded_next_uri: str = encode_next(NEXT_URI)
 
         self.client, self.csrf_token = get_client(self.app, "editor")
 
@@ -60,7 +62,7 @@ class UnmatchedOffsetTestCase(unittest.TestCase):
 
         response = client.post(f"{PREFIX}/{Accounts.PAYABLE}",
                                data={"csrf_token": csrf_token,
-                                     "next": NEXT_URI})
+                                     "next": self.encoded_next_uri})
         self.assertEqual(response.status_code, 403)
 
     def test_viewer(self) -> None:
@@ -74,7 +76,7 @@ class UnmatchedOffsetTestCase(unittest.TestCase):
 
         response = client.post(f"{PREFIX}/{Accounts.PAYABLE}",
                                data={"csrf_token": csrf_token,
-                                     "next": NEXT_URI})
+                                     "next": self.encoded_next_uri})
         self.assertEqual(response.status_code, 403)
 
     def test_editor(self) -> None:
@@ -87,7 +89,7 @@ class UnmatchedOffsetTestCase(unittest.TestCase):
 
         response = self.client.post(f"{PREFIX}/{Accounts.PAYABLE}",
                                     data={"csrf_token": self.csrf_token,
-                                          "next": NEXT_URI})
+                                          "next": self.encoded_next_uri})
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], NEXT_URI)
 
@@ -100,7 +102,7 @@ class UnmatchedOffsetTestCase(unittest.TestCase):
 
         response = self.client.post(f"{PREFIX}/{Accounts.PAYABLE}",
                                     data={"csrf_token": self.csrf_token,
-                                          "next": NEXT_URI})
+                                          "next": self.encoded_next_uri})
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], NEXT_URI)
 
@@ -150,7 +152,7 @@ class UnmatchedOffsetTestCase(unittest.TestCase):
         match_uri = f"{PREFIX}/{Accounts.RECEIVABLE}"
         response = self.client.post(match_uri,
                                     data={"csrf_token": self.csrf_token,
-                                          "next": NEXT_URI})
+                                          "next": self.encoded_next_uri})
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], NEXT_URI)
 
@@ -200,7 +202,7 @@ class UnmatchedOffsetTestCase(unittest.TestCase):
         match_uri = f"{PREFIX}/{Accounts.PAYABLE}"
         response = self.client.post(match_uri,
                                     data={"csrf_token": self.csrf_token,
-                                          "next": NEXT_URI})
+                                          "next": self.encoded_next_uri})
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], NEXT_URI)
 
@@ -278,7 +280,7 @@ class UnmatchedOffsetTestCase(unittest.TestCase):
         match_uri = f"{PREFIX}/{Accounts.RECEIVABLE}"
         response = self.client.post(match_uri,
                                     data={"csrf_token": self.csrf_token,
-                                          "next": NEXT_URI})
+                                          "next": self.encoded_next_uri})
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], NEXT_URI)
 
@@ -344,7 +346,7 @@ class UnmatchedOffsetTestCase(unittest.TestCase):
         match_uri = f"{PREFIX}/{Accounts.PAYABLE}"
         response = self.client.post(match_uri,
                                     data={"csrf_token": self.csrf_token,
-                                          "next": NEXT_URI})
+                                          "next": self.encoded_next_uri})
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response.headers["Location"], NEXT_URI)
 

tests/test_utils.py

@@ -22,11 +22,12 @@ from urllib.parse import quote_plus
 
 import httpx
 from flask import Flask, request
+from itsdangerous import URLSafeSerializer
 
 from accounting.utils.next_uri import append_next, inherit_next, or_next
 from accounting.utils.pagination import Pagination, DEFAULT_PAGE_SIZE
 from accounting.utils.query import parse_query_keywords
-from testlib import TEST_SERVER, create_test_app, get_csrf_token
+from testlib import TEST_SERVER, create_test_app, get_csrf_token, NEXT_URI
 
 
 class NextUriTestCase(unittest.TestCase):
@@ -40,6 +41,8 @@ class NextUriTestCase(unittest.TestCase):
         :return: None.
         """
         self.app: Flask = create_test_app()
+        self.serializer: URLSafeSerializer \
+            = URLSafeSerializer(self.app.config["SECRET_KEY"])
 
     def test_next_uri(self) -> None:
         """Tests the next URI utilities with the next URI.
@@ -51,12 +54,12 @@ class NextUriTestCase(unittest.TestCase):
             current_uri: str = request.full_path if request.query_string \
                 else request.path
             self.assertEqual(append_next(self.TARGET),
-                             f"{self.TARGET}?next={quote_plus(current_uri)}")
+                             f"{self.TARGET}?next={self.__encode(current_uri)}")
             next_uri: str = request.form["next"] if request.method == "POST" \
                 else request.args["next"]
             self.assertEqual(inherit_next(self.TARGET),
-                             f"{self.TARGET}?next={quote_plus(next_uri)}")
-            self.assertEqual(or_next(self.TARGET), next_uri)
+                             f"{self.TARGET}?next={next_uri}")
+            self.assertEqual(or_next(self.TARGET), self.__decode(next_uri))
             return ""
 
         self.app.add_url_rule("/test-next", view_func=test_next_uri_view,
@@ -66,10 +69,11 @@ class NextUriTestCase(unittest.TestCase):
         csrf_token: str = get_csrf_token(client)
         response: httpx.Response
 
-        response = client.get("/test-next?next=/next&q=abc&page-no=4")
+        encoded_uri: str = self.__encode(NEXT_URI)
+        response = client.get(f"/test-next?next={encoded_uri}&q=abc&page-no=4")
         self.assertEqual(response.status_code, 200)
         response = client.post("/test-next", data={"csrf_token": csrf_token,
-                                                   "next": "/next",
+                                                   "next": encoded_uri,
                                                    "name": "viewer"})
         self.assertEqual(response.status_code, 200)
 
@@ -80,10 +84,6 @@ class NextUriTestCase(unittest.TestCase):
         """
         def test_no_next_uri_view() -> str:
             """The test view without the next URI."""
-            current_uri: str = request.full_path if request.query_string \
-                else request.path
-            self.assertEqual(append_next(self.TARGET),
-                             f"{self.TARGET}?next={quote_plus(current_uri)}")
             self.assertEqual(inherit_next(self.TARGET), self.TARGET)
             self.assertEqual(or_next(self.TARGET), self.TARGET)
             return ""
@@ -108,10 +108,8 @@ class NextUriTestCase(unittest.TestCase):
         """
         def test_invalid_next_uri_view() -> str:
             """The test view without the next URI."""
-            self.assertEqual(inherit_next(self.TARGET),
-                             request.args.get("inherit-expected"))
-            self.assertEqual(or_next(self.TARGET),
-                             request.args.get("or-expected"))
+            self.assertEqual(inherit_next(self.TARGET), self.TARGET)
+            self.assertEqual(or_next(self.TARGET), self.TARGET)
             return ""
 
         self.app.add_url_rule("/test-invalid-next",
@@ -127,19 +125,29 @@ class NextUriTestCase(unittest.TestCase):
 
         # A foreign URI
         next_uri = "https://example.com"
-        expected1 = self.TARGET
-        expected2 = self.TARGET
-        response = client.get(f"/test-invalid-next?next={quote_plus(next_uri)}"
-                              f"&inherit-expected={quote_plus(expected1)}"
-                              f"&or-expected={quote_plus(expected2)}")
+        response = client.get(f"/test-invalid-next?next={quote_plus(next_uri)}")
         self.assertEqual(response.status_code, 200)
-        response = client.post("/test-invalid-next"
-                               f"?inherit-expected={quote_plus(expected1)}"
-                               f"&or-expected={quote_plus(expected2)}",
+        response = client.post("/test-invalid-next",
                                data={"csrf_token": csrf_token,
                                      "next": next_uri})
         self.assertEqual(response.status_code, 200)
 
+    def __encode(self, uri: str) -> str:
+        """Encodes the next URI.
+
+        :param uri: The next URI.
+        :return: The encoded next URI.
+        """
+        return self.serializer.dumps(uri, "next")
+
+    def __decode(self, uri: str) -> str:
+        """Decodes the next URI.
+
+        :param uri: The encoded next URI.
+        :return: The next URI.
+        """
+        return self.serializer.loads(uri, "next")
+
 
 class QueryKeywordParserTestCase(unittest.TestCase):
     """The test case for the query keyword parser."""

tests/testlib.py

@@ -25,6 +25,7 @@ from typing import Literal
 import httpx
 from flask import Flask, render_template_string
 
+from accounting.utils.next_uri import encode_next
 from test_site import create_app
 
 TEST_SERVER: str = "https://testserver"
@@ -71,9 +72,9 @@ def create_test_app() -> Flask:
         """The test view to return the CSRF token."""
         return render_template_string("{{csrf_token()}}")
 
-    @app.get("/.errors")
-    def get_errors_view() -> str:
-        """The test view to return the CSRF token."""
+    @app.get("/.messages")
+    def get_messages_view() -> str:
+        """The test view to return the flashed messages."""
         return render_template_string("{{get_flashed_messages()|tojson}}")
 
     return app
@@ -98,30 +99,35 @@ def get_client(app: Flask, username: str) -> tuple[httpx.Client, str]:
     client: httpx.Client = httpx.Client(app=app, base_url=TEST_SERVER)
     client.headers["Referer"] = TEST_SERVER
     csrf_token: str = get_csrf_token(client)
+    with app.app_context():
+        encoded_next_uri: str = encode_next(NEXT_URI)
     response: httpx.Response = client.post("/login",
                                            data={"csrf_token": csrf_token,
-                                                 "next": "/",
+                                                 "next": encoded_next_uri,
                                                  "username": username})
     assert response.status_code == 302
-    assert response.headers["Location"] == "/"
+    assert response.headers["Location"] == NEXT_URI
     return client, csrf_token
 
 
-def set_locale(client: httpx.Client, csrf_token: str,
+def set_locale(app: Flask, client: httpx.Client, csrf_token: str,
                locale: Literal["en", "zh_Hant", "zh_Hans"]) -> None:
     """Sets the current locale.
 
+    :param app: The Flask application.
     :param client: The test client.
     :param csrf_token: The CSRF token.
     :param locale: The locale.
     :return: None.
     """
+    with app.app_context():
+        encoded_next_uri: str = encode_next(NEXT_URI)
     response: httpx.Response = client.post("/locale",
                                            data={"csrf_token": csrf_token,
                                                  "locale": locale,
-                                                 "next": "/next"})
+                                                 "next": encoded_next_uri})
     assert response.status_code == 302
-    assert response.headers["Location"] == "/next"
+    assert response.headers["Location"] == NEXT_URI
 
 
 def add_journal_entry(client: httpx.Client, form: dict[str, str]) -> int:
@@ -152,6 +158,6 @@ def match_journal_entry_detail(location: str) -> int:
     :raise AssertionError: When the location is not the journal entry detail.
     """
     m: re.Match = re.match(
-        r"^/accounting/journal-entries/(\d+)\?next=%2F_next", location)
+        r"^/accounting/journal-entries/(\d+)\?next=", location)
     assert m is not None
     return int(m.group(1))

tests/testlib_journal_entry.py

@@ -33,14 +33,15 @@ EMPTY_NOTE: str = " \n\n  "
 """The empty note content."""
 
 
-def get_add_form(csrf_token: str) -> dict[str, str]:
+def get_add_form(csrf_token: str, encoded_next_uri: str) -> dict[str, str]:
     """Returns the form data to add a new journal entry.
 
     :param csrf_token: The CSRF token.
+    :param encoded_next_uri: The encoded next URI.
     :return: The form data to add a new journal entry.
     """
     return {"csrf_token": csrf_token,
-            "next": NEXT_URI,
+            "next": encoded_next_uri,
             "date": dt.date.today().isoformat(),
             "currency-0-code": "USD",
             "currency-0-debit-0-no": "16",
@@ -102,13 +103,15 @@ def get_add_form(csrf_token: str) -> dict[str, str]:
 
 
 def get_unchanged_update_form(journal_entry_id: int, app: Flask,
-                              csrf_token: str) -> dict[str, str]:
+                              csrf_token: str, encoded_next_uri: str) \
+        -> dict[str, str]:
     """Returns the form data to update a journal entry, where the data are not
     changed.
 
     :param journal_entry_id: The journal entry ID.
     :param app: The Flask application.
     :param csrf_token: The CSRF token.
+    :param encoded_next_uri: The encoded next URI.
     :return: The form data to update the journal entry, where the data are not
         changed.
     """
@@ -121,7 +124,7 @@ def get_unchanged_update_form(journal_entry_id: int, app: Flask,
 
     form: dict[str, str] \
         = {"csrf_token": csrf_token,
-           "next": NEXT_URI,
+           "next": encoded_next_uri,
            "date": journal_entry.date,
            "note": "  \n \n\n  " if journal_entry.note is None
            else f"\n    \n\n \n  \n{journal_entry.note}  \n\n   "}
@@ -182,20 +185,22 @@ def __get_new_index(indices_used: set[int]) -> int:
 
 
 def get_update_form(journal_entry_id: int, app: Flask,
-                    csrf_token: str, is_debit: bool | None) -> dict[str, str]:
+                    csrf_token: str, encoded_next_uri: str,
+                    is_debit: bool | None) -> dict[str, str]:
     """Returns the form data to update a journal entry, where the data are
     changed.
 
     :param journal_entry_id: The journal entry ID.
     :param app: The Flask application.
     :param csrf_token: The CSRF token.
+    :param encoded_next_uri: The encoded next URI.
     :param is_debit: True for a cash disbursement journal entry, False for a
         cash receipt journal entry, or None for a transfer journal entry.
     :return: The form data to update the journal entry, where the data are
         changed.
     """
     form: dict[str, str] = get_unchanged_update_form(
-        journal_entry_id, app, csrf_token)
+        journal_entry_id, app, csrf_token, encoded_next_uri)
 
     # Mess up the line items in a currency
     currency_prefix: str = __get_currency_prefix(form, "USD")