Fixed #18990: Loaddata now complains if fixture doesn't exist

The fixture named "initial_data" is exceptional though; if it
doesn't exist, the error is not raised. This allows syncdb and
flush management commands to attempt to load it without causing
an error if it doesn't exist.

django/core/management/commands/loaddata.py

@@ -162,9 +162,14 @@ class Command(BaseCommand):
         else:
             fixture_dirs = app_fixtures + list(settings.FIXTURE_DIRS) + ['']
 
+        label_found = False
         for fixture_dir in fixture_dirs:
-            self.process_dir(fixture_dir, fixture_name, compression_formats,
-                             formats)
+            found = self.process_dir(fixture_dir, fixture_name,
+                compression_formats, formats)
+            label_found = label_found or found
+
+        if fixture_name != 'initial_data' and not label_found:
+            raise CommandError("No fixture named '%s' found." % fixture_name)
 
     def process_dir(self, fixture_dir, fixture_name, compression_formats,
                     serialization_formats):
@@ -242,3 +247,5 @@ class Command(BaseCommand):
                     raise CommandError(
                         "No fixture data found for '%s'. (File format may be invalid.)" %
                             (fixture_name))
+
+        return label_found

tests/fixtures/tests.py

@@ -137,8 +137,14 @@ class FixtureLoadingTests(DumpDataAssertMixin, TestCase):
             '<Book: Music for all ages by Artist formerly known as "Prince" and Django Reinhardt>'
         ])
 
-        # Load a fixture that doesn't exist
-        management.call_command('loaddata', 'unknown.json', verbosity=0, commit=False)
+        # Loading a fixture that doesn't exist results in an error
+        with self.assertRaises(management.CommandError):
+            management.call_command('loaddata', 'unknown.json', verbosity=0,
+                commit=False)
+
+        # An attempt to load a nonexistent 'initial_data' fixture isn't an error
+        management.call_command('loaddata', 'initial_data.json', verbosity=0,
+            commit=False)
 
         # object list is unaffected
         self.assertQuerysetEqual(Article.objects.all(), [
@@ -273,9 +279,10 @@ class FixtureLoadingTests(DumpDataAssertMixin, TestCase):
 
     def test_unmatched_identifier_loading(self):
         # Try to load db fixture 3. This won't load because the database identifier doesn't match
+        with self.assertRaises(management.CommandError):
             management.call_command('loaddata', 'db_fixture_3', verbosity=0, commit=False)
-        self.assertQuerysetEqual(Article.objects.all(), [])
 
+        with self.assertRaises(management.CommandError):
             management.call_command('loaddata', 'db_fixture_3', verbosity=0, using='default', commit=False)
         self.assertQuerysetEqual(Article.objects.all(), [])
 

tests/fixtures_regress/tests.py

@@ -441,6 +441,7 @@ class TestFixtures(TestCase):
 
     def test_loaddata_not_existant_fixture_file(self):
         stdout_output = StringIO()
+        with self.assertRaises(management.CommandError):
             management.call_command(
                 'loaddata',
                 'this_fixture_doesnt_exist',