Add a test run without Flask-Babel installed

Adds a `flask_babel` mark to any tests that explicitly require
`Flask-Babel` to be installed.

Configures tox and GitHub Actions to run a test suite with Flask-Babel
removed. This validates a codepath through `flask_admin.babel`, which
should essentially be passthrough/noop behaviour if Flask-Babel is
unavailable.

.github/workflows/tests.yaml

@@ -15,13 +15,20 @@ on:
       - '*.rst'
 jobs:
   tests:
-    name: ${{ format('py{0}-wtforms{1}', matrix.python, matrix.wtforms) }}
+    name: ${{ matrix.tox == 'normal' && format('py{0}-flask{1}-wtforms{2}', matrix.python, matrix.flask, matrix.wtforms) || matrix.tox }}
     runs-on: ${{ matrix.os || 'ubuntu-latest' }}
     strategy:
       fail-fast: false
       matrix:
         python: ['3.8', '3.9', '3.10', '3.11', '3.12']
+        flask: ['2']
         wtforms: ['2']
+        tox: ['normal']
+        include:
+          - python: '3.12'
+            flask: '2'
+            wtforms: '2'
+            tox: 'py312-flask2-wtforms2-no-flask-babel'
     services:
       # Label used to access the service container
       postgres:
@@ -68,7 +75,7 @@ jobs:
           PGPASSWORD: postgres
         run: psql -U postgres -h localhost -c 'CREATE EXTENSION hstore;' flask_admin_test
       - run: pip install tox
-      - run: tox run -e ${{ matrix.tox || format('py{0}-wtforms{1}', matrix.python, matrix.wtforms) }}
+      - run: tox run -e ${{ matrix.tox == 'normal' && format('py{0}-flask{1}-wtforms{2}', matrix.python, matrix.flask, matrix.wtforms) || matrix.tox }}
   not_tests:
     name: ${{ matrix.tox }}
     runs-on: ubuntu-latest

flask_admin/tests/sqla/test_basic.py

@@ -2181,6 +2181,7 @@ def test_extra_field_order(app, db, admin):
         ('zh_TW', '首頁'),
     )
 )
+@pytest.mark.flask_babel
 def test_modelview_localization(request, app, locale, expect_text):
     # We need to configure the default Babel locale _before_ the `babel` fixture is
     # initialised, so we have to use `request.getfixturevalue` to pull the fixture
@@ -2210,6 +2211,7 @@ def test_modelview_localization(request, app, locale, expect_text):
         assert rv.status_code == 200
 
 
+@pytest.mark.flask_babel
 def test_modelview_named_filter_localization(request, app):
     # We need to configure the default Babel locale _before_ the `babel` fixture is
     # initialised, so we have to use `request.getfixturevalue` to pull the fixture

flask_admin/tests/sqla/test_translation.py

@@ -1,8 +1,11 @@
+import pytest
+
 from flask_admin.babel import lazy_gettext
 
 from .test_basic import CustomModelView, create_models
 
 
+@pytest.mark.flask_babel
 def test_column_label_translation(request, app):
     # We need to configure the default Babel locale _before_ the `babel` fixture is
     # initialised, so we have to use `request.getfixturevalue` to pull the fixture

pyproject.toml

@@ -41,6 +41,9 @@ name = "flask_admin"
 
 [tool.pytest.ini_options]
 testpaths = ["tests"]
+markers = [
+    "flask_babel: requires Flask-Babel to be installed"
+]
 filterwarnings = [
     "error",
     # TODO: remove the ignored deprecation warning when support for WTForms 3 has been added.

tox.ini

@@ -1,6 +1,7 @@
 [tox]
 envlist =
     py3{8,9,10,11,12}-flask{2}-wtforms{2}
+    py312-flask2-wtforms2-no-flask-babel  # only tested against latest of all configurations, sans flask-babel
 #     style
     typing
     docs
@@ -23,6 +24,11 @@ deps =
     wtforms2: WTForms>=2.0,<3
 commands = pytest -v --tb=short --basetemp={envtmpdir} flask_admin/tests {posargs}
 
+[testenv:py312-flask2-wtforms2-no-flask-babel]
+commands =
+    pip uninstall -y flask-babel
+    pytest -v --tb=short --basetemp={envtmpdir} flask_admin/tests -m "not flask_babel" {posargs}
+
 [testenv:style]
 deps = pre-commit
 skip_install = true