Refs #36680 -- Avoided manipulating PATH in AdminScriptTestCase.

This mostly reverts 6436ec321073bf0622af815e0af08f54c97f9b30,
which was fragile. Instead, if black is present, we use it to format the
expected and actual results, instead of hard-coding the expected
formatted value.

Co-authored-by: Natalia <124304+nessita@users.noreply.github.com>

1 files changed, 28 insertions, 45 deletions

diff --git a/tests/admin_scripts/tests.py b/tests/admin_scripts/tests.py
index c01a5571dc..0c27194568 100644
--- a/tests/admin_scripts/tests.py
+++ b/tests/admin_scripts/tests.py
@@ -33,13 +33,11 @@ from django.core.management.base import LabelCommand, SystemCheckError
 from django.core.management.commands.loaddata import Command as LoaddataCommand
 from django.core.management.commands.runserver import Command as RunserverCommand
 from django.core.management.commands.testserver import Command as TestserverCommand
-from django.core.management.utils import find_formatters
 from django.db import ConnectionHandler, connection
 from django.db.migrations.recorder import MigrationRecorder
 from django.test import LiveServerTestCase, SimpleTestCase, TestCase, override_settings
 from django.test.utils import captured_stderr, captured_stdout
 from django.urls import path
-from django.utils.functional import cached_property
 from django.utils.version import PY313, get_docs_version
 from django.views.static import serve
 
@@ -49,6 +47,8 @@ custom_templates_dir = os.path.join(os.path.dirname(__file__), "custom_templates
 
 SYSTEM_CHECK_MSG = "System check identified no issues"
 
+HAS_BLACK = shutil.which("black")
+
 
 class AdminScriptTestCase(SimpleTestCase):
     def setUp(self):
@@ -112,21 +112,7 @@ class AdminScriptTestCase(SimpleTestCase):
                 paths.append(os.path.dirname(backend_dir))
         return paths
 
-    @cached_property
-    def path_without_formatters(self):
-        return os.pathsep.join(
-            [
-                path_component
-                for path_component in os.environ.get("PATH", "").split(os.pathsep)
-                for formatter_path in find_formatters().values()
-                if formatter_path
-                and os.path.commonpath([path_component, formatter_path]) == os.sep
-            ]
-        )
-
-    def run_test(
-        self, args, settings_file=None, apps=None, umask=-1, discover_formatters=False
-    ):
+    def run_test(self, args, settings_file=None, apps=None, umask=-1):
         base_dir = os.path.dirname(self.test_dir)
         # The base dir for Django's tests is one level up.
         tests_dir = os.path.dirname(os.path.dirname(__file__))
@@ -148,8 +134,6 @@ class AdminScriptTestCase(SimpleTestCase):
         python_path.extend(ext_backend_base_dirs)
         test_environ["PYTHONPATH"] = os.pathsep.join(python_path)
         test_environ["PYTHONWARNINGS"] = ""
-        if not discover_formatters:
-            test_environ["PATH"] = self.path_without_formatters
 
         p = subprocess.run(
             [sys.executable, *args],
@@ -161,19 +145,10 @@ class AdminScriptTestCase(SimpleTestCase):
         )
         return p.stdout, p.stderr
 
-    def run_django_admin(
-        self, args, settings_file=None, umask=-1, discover_formatters=False
-    ):
-        return self.run_test(
-            ["-m", "django", *args],
-            settings_file,
-            umask=umask,
-            discover_formatters=discover_formatters,
-        )
+    def run_django_admin(self, args, settings_file=None, umask=-1):
+        return self.run_test(["-m", "django", *args], settings_file, umask=umask)
 
-    def run_manage(
-        self, args, settings_file=None, manage_py=None, discover_formatters=False
-    ):
+    def run_manage(self, args, settings_file=None, manage_py=None):
         template_manage_py = (
             os.path.join(os.path.dirname(__file__), manage_py)
             if manage_py
@@ -192,11 +167,17 @@ class AdminScriptTestCase(SimpleTestCase):
         with open(test_manage_py, "w") as fp:
             fp.write(manage_py_contents)
 
-        return self.run_test(
-            ["./manage.py", *args],
-            settings_file,
-            discover_formatters=discover_formatters,
-        )
+        return self.run_test(["./manage.py", *args], settings_file)
+
+    def assertInAfterFormatting(self, member, container, msg=None):
+        if HAS_BLACK:
+            import black
+
+            # Black does not have a stable API, but this is still less fragile
+            # than attempting to filter out all paths where it is available.
+            member = black.format_str(member, mode=black.FileMode())
+
+        self.assertIn(member, container, msg=msg)
 
     def assertNoOutput(self, stream):
         "Utility assertion: assert that the given stream is empty"
@@ -773,7 +754,7 @@ class DjangoAdminSettingsDirectory(AdminScriptTestCase):
         with open(os.path.join(app_path, "apps.py")) as f:
             content = f.read()
             self.assertIn("class SettingsTestConfig(AppConfig)", content)
-            self.assertIn("name = 'settings_test'", content)
+            self.assertInAfterFormatting("name = 'settings_test'", content)
 
     def test_setup_environ_custom_template(self):
         """
@@ -798,7 +779,7 @@ class DjangoAdminSettingsDirectory(AdminScriptTestCase):
         with open(os.path.join(app_path, "apps.py"), encoding="utf8") as f:
             content = f.read()
             self.assertIn("class こんにちはConfig(AppConfig)", content)
-            self.assertIn("name = 'こんにちは'", content)
+            self.assertInAfterFormatting("name = 'こんにちは'", content)
 
     def test_builtin_command(self):
         """
@@ -1960,7 +1941,7 @@ class CommandTypes(AdminScriptTestCase):
     def test_version(self):
         "version is handled as a special case"
         args = ["version"]
-        out, err = self.run_manage(args, discover_formatters=True)
+        out, err = self.run_manage(args)
         self.assertNoOutput(err)
         self.assertOutput(out, get_version())
 
@@ -2713,7 +2694,7 @@ class StartProject(LiveServerTestCase, AdminScriptTestCase):
         args = ["startproject", "--template", template_path, "customtestproject"]
         testproject_dir = os.path.join(self.test_dir, "customtestproject")
 
-        _, err = self.run_django_admin(args, discover_formatters=True)
+        _, err = self.run_django_admin(args)
         self.assertNoOutput(err)
         with open(
             os.path.join(template_path, "additional_dir", "requirements.in")
@@ -2808,7 +2789,7 @@ class StartProject(LiveServerTestCase, AdminScriptTestCase):
                 f"{self.live_server_url}/user_agent_check/project_template.tgz"
             )
             args = ["startproject", "--template", template_url, "urltestproject"]
-            _, err = self.run_django_admin(args, discover_formatters=True)
+            _, err = self.run_django_admin(args)
 
             self.assertNoOutput(err)
             self.assertIn("Django/%s" % get_version(), user_agent)
@@ -2879,8 +2860,10 @@ class StartProject(LiveServerTestCase, AdminScriptTestCase):
         test_manage_py = os.path.join(testproject_dir, "manage.py")
         with open(test_manage_py) as fp:
             content = fp.read()
-            self.assertIn('project_name = "another_project"', content)
-            self.assertIn('project_directory = "%s"' % testproject_dir, content)
+            self.assertInAfterFormatting('project_name = "another_project"', content)
+            self.assertInAfterFormatting(
+                'project_directory = "%s"' % testproject_dir, content
+            )
 
     def test_no_escaping_of_project_variables(self):
         "Make sure template context variables are not html escaped"
@@ -2990,7 +2973,7 @@ class StartProject(LiveServerTestCase, AdminScriptTestCase):
         self.assertNoOutput(err)
         render_py_path = os.path.join(testproject_dir, ".hidden", "render.py")
         with open(render_py_path) as fp:
-            self.assertIn(
+            self.assertInAfterFormatting(
                 f"# The {project_name} should be rendered.",
                 fp.read(),
             )
@@ -3150,7 +3133,7 @@ class StartApp(AdminScriptTestCase):
         with open(os.path.join(app_path, "apps.py")) as f:
             content = f.read()
             self.assertIn("class NewAppConfig(AppConfig)", content)
-            self.assertIn("name = 'new_app'", content)
+            self.assertInAfterFormatting("name = 'new_app'", content)
 
     def test_creates_directory_when_custom_app_destination_missing(self):
         args = [