Update old string formatting to f-strings (#1018)

docs/conf.py

@@ -27,7 +27,7 @@
 
 # General information about the project.
 project = 'pytest-django'
-copyright = '%d, Andreas Pelme and contributors' % datetime.date.today().year
+copyright = f'{datetime.date.today().year}, Andreas Pelme and contributors'
 
 exclude_patterns = ['_build']
 

pytest_django/fixtures.py

@@ -132,7 +132,7 @@ def teardown_database() -> None:
             except Exception as exc:
                 request.node.warn(
                     pytest.PytestWarning(
-                        "Error when trying to teardown test databases: %r" % exc
+                        f"Error when trying to teardown test databases: {exc!r}"
                     )
                 )
 
@@ -287,7 +287,7 @@ def _set_suffix_to_test_databases(suffix: str) -> None:
         if not test_name:
             if db_settings["ENGINE"] == "django.db.backends.sqlite3":
                 continue
-            test_name = "test_{}".format(db_settings["NAME"])
+            test_name = f"test_{db_settings['NAME']}"
 
         if test_name == ":memory:":
             continue
@@ -591,13 +591,11 @@ def _assert_num_queries(
         else:
             failed = num_performed > num
         if failed:
-            msg = "Expected to perform {} queries {}{}".format(
-                num,
-                "" if exact else "or less ",
-                "but {} done".format(
-                    num_performed == 1 and "1 was" or f"{num_performed} were"
-                ),
-            )
+            msg = f"Expected to perform {num} queries "
+            if not exact:
+                msg += "or less "
+            verb = "was" if num_performed == 1 else "were"
+            msg += f"but {num_performed} {verb} done"
             if info:
                 msg += f"\n{info}"
             if verbose:

pytest_django/live_server_helper.py

@@ -78,4 +78,4 @@ def __add__(self, other) -> str:
         return f"{self}{other}"
 
     def __repr__(self) -> str:
-        return "<LiveServer listening at %s>" % self.url
+        return f"<LiveServer listening at {self.url}>"

pytest_django/plugin.py

@@ -251,9 +251,9 @@ def _get_boolean_value(
     try:
         return possible_values[x.lower()]
     except KeyError:
+        possible = ", ".join(possible_values)
         raise ValueError(
-            "{} is not a valid value for {}. "
-            "It must be one of {}.".format(x, name, ", ".join(possible_values.keys()))
+            f"{x} is not a valid value for {name}. It must be one of {possible}."
         )
 
 
@@ -621,7 +621,7 @@ def __mod__(self, var: str) -> str:
             if origin:
                 msg = f"Undefined template variable '{var}' in '{origin}'"
             else:
-                msg = "Undefined template variable '%s'" % var
+                msg = f"Undefined template variable '{var}'"
             if self.fail:
                 pytest.fail(msg)
             else:

pytest_django_test/app/views.py

@@ -11,4 +11,4 @@ def admin_required_view(request: HttpRequest) -> HttpResponse:
 
 
 def item_count(request: HttpRequest) -> HttpResponse:
-    return HttpResponse("Item count: %d" % Item.objects.count())
+    return HttpResponse(f"Item count: {Item.objects.count()}")

pytest_django_test/db_helpers.py

@@ -102,18 +102,18 @@ def drop_database(db_suffix=None):
     db_engine = get_db_engine()
 
     if db_engine == "postgresql":
-        r = run_psql("postgres", "-c", "DROP DATABASE %s" % name)
+        r = run_psql("postgres", "-c", f"DROP DATABASE {name}")
         assert "DROP DATABASE" in force_str(
             r.std_out
         ) or "does not exist" in force_str(r.std_err)
         return
 
     if db_engine == "mysql":
-        r = run_mysql("-e", "DROP DATABASE %s" % name)
+        r = run_mysql("-e", f"DROP DATABASE {name}")
         assert "database doesn't exist" in force_str(r.std_err) or r.status_code == 0
         return
 
-    assert db_engine == "sqlite3", "%s cannot be tested properly!" % db_engine
+    assert db_engine == "sqlite3", f"{db_engine} cannot be tested properly!"
     assert name != ":memory:", "sqlite in-memory database cannot be dropped!"
     if os.path.exists(name):  # pragma: no branch
         os.unlink(name)
@@ -131,7 +131,7 @@ def db_exists(db_suffix=None):
         r = run_mysql(name, "-e", "SELECT 1")
         return r.status_code == 0
 
-    assert db_engine == "sqlite3", "%s cannot be tested properly!" % db_engine
+    assert db_engine == "sqlite3", f"{db_engine} cannot be tested properly!"
     assert TEST_DB_NAME != ":memory:", (
         "sqlite in-memory database cannot be checked for existence!")
     return os.path.exists(name)
@@ -150,7 +150,7 @@ def mark_database():
         assert r.status_code == 0
         return
 
-    assert db_engine == "sqlite3", "%s cannot be tested properly!" % db_engine
+    assert db_engine == "sqlite3", f"{db_engine} cannot be tested properly!"
     assert TEST_DB_NAME != ":memory:", (
         "sqlite in-memory database cannot be marked!")
 
@@ -175,7 +175,7 @@ def mark_exists():
 
         return r.status_code == 0
 
-    assert db_engine == "sqlite3", "%s cannot be tested properly!" % db_engine
+    assert db_engine == "sqlite3", f"{db_engine} cannot be tested properly!"
     assert TEST_DB_NAME != ":memory:", (
         "sqlite in-memory database cannot be checked for mark!")
 

tests/test_django_settings_module.py

@@ -310,12 +310,10 @@ def test_debug_is_false():
 @pytest.mark.parametrize('django_debug_mode', (False, True))
 def test_django_debug_mode_true_false(testdir, monkeypatch, django_debug_mode: bool) -> None:
     monkeypatch.delenv("DJANGO_SETTINGS_MODULE")
-    testdir.makeini(
-        """
+    testdir.makeini(f"""
        [pytest]
-       django_debug_mode = {}
-    """.format(django_debug_mode)
-    )
+       django_debug_mode = {django_debug_mode}
+    """)
     testdir.makeconftest(
         """
         from django.conf import settings
@@ -331,13 +329,11 @@ def pytest_configure():
     """ % (not django_debug_mode)
     )
 
-    testdir.makepyfile(
-        """
+    testdir.makepyfile(f"""
         from django.conf import settings
         def test_debug_is_false():
-            assert settings.DEBUG is {}
-    """.format(django_debug_mode)
-    )
+            assert settings.DEBUG is {django_debug_mode}
+    """)
 
     r = testdir.runpytest_subprocess()
     assert r.ret == 0
@@ -368,11 +364,11 @@ def pytest_configure():
     )
 
     testdir.makepyfile(
-        """
+        f"""
         from django.conf import settings
         def test_debug_is_false():
-            assert settings.DEBUG is {}
-    """.format(settings_debug)
+            assert settings.DEBUG is {settings_debug}
+    """
     )
 
     r = testdir.runpytest_subprocess()

tests/test_environment.py

@@ -96,9 +96,7 @@ def test_ignore(client):
     result.stdout.fnmatch_lines_random(
         [
             "tpkg/test_the_test.py F.*",
-            "E * Failed: Undefined template variable 'invalid_var' in {}".format(
-                origin
-            ),
+            f"E * Failed: Undefined template variable 'invalid_var' in {origin}",
         ]
     )
 

tests/test_fixtures.py

@@ -546,7 +546,7 @@ def test_with_live_server(live_server):
             % port
         )
 
-        django_testdir.runpytest_subprocess("--liveserver=localhost:%s" % port)
+        django_testdir.runpytest_subprocess(f"--liveserver=localhost:{port}")
 
 
 @pytest.mark.parametrize("username_field", ("email", "identifier"))
@@ -565,7 +565,7 @@ def test_with_live_server(live_server):
 )
 def test_custom_user_model(django_testdir, username_field) -> None:
     django_testdir.create_app_file(
-        """
+        f"""
         from django.contrib.auth.models import AbstractBaseUser, BaseUserManager, PermissionsMixin
         from django.db import models
 
@@ -599,7 +599,7 @@ class MyCustomUser(AbstractBaseUser, PermissionsMixin):
             objects = MyCustomUserManager()
 
             USERNAME_FIELD = '{username_field}'
-        """.format(username_field=username_field),
+        """,
         "models.py",
     )
     django_testdir.create_app_file(