Support apps with custom label.

CHANGELOG.md

@@ -1,8 +1,11 @@
-## x.y.z
+## 6.0.0
+
+Feature:
+- **Breaking change**: Handle custom Django app label when gathering migrations from git reference. (#262)
+This means that, an app that was previously referenced by its folder name, will now be referenced by its Django app label.
 
 Miscellaneous:
-
-- Add py.typed file
+- Add py.typed file (#303)
 
 ## 5.2.0
 

src/django_migration_linter/migration_linter.py

@@ -7,8 +7,9 @@ import logging
 import os
 import re
 from enum import Enum, unique
+from importlib.util import find_spec
 from subprocess import PIPE, Popen
-from typing import Callable, Iterable
+from typing import Callable, Dict, Iterable
 
 from django.conf import settings
 from django.core.management import call_command
@@ -389,7 +390,6 @@ class MigrationLinter:
     def _gather_migrations_git(
         self, git_commit_id: str, migrations_list: list[tuple[str, str]] | None = None
     ) -> Iterable[Migration]:
-        migrations = []
         # Get changes since specified commit
         git_diff_command = [
             "git",
@@ -406,19 +406,44 @@ class MigrationLinter:
             stderr=PIPE,
             cwd=self.django_path,
         )
+
+        diskpath_and_migration: Dict[str, Migration] = {}
+        for migration in self._gather_all_migrations():
+            spec = find_spec(migration.__module__)
+            if spec:
+                diskpath_and_migration[str(spec.origin)] = migration
+
+        migrations = []
         for line in map(
             clean_bytes_to_str, diff_process.stdout.readlines()  # type: ignore
         ):
-            # Only gather lines that include added migrations
+            # Only gather lines that include added migrations.
             if self.is_migration_file(line):
-                app_label, name = split_migration_path(line)
-                if migrations_list is None or (app_label, name) in migrations_list:
-                    if (app_label, name) in self.migration_loader.disk_migrations:
-                        migration = self.migration_loader.disk_migrations[
-                            app_label, name
+                # Find the migration objects with similar path.
+                suitable_migrations = [
+                    migration
+                    for path, migration in diskpath_and_migration.items()
+                    if path.endswith(line)
                 ]
+                if suitable_migrations:
+                    migration = suitable_migrations[0]
+                    if (
+                        migrations_list is None
+                        or (migration.app_label, migration.name) in migrations_list
+                    ):
                         migrations.append(migration)
+                    if len(suitable_migrations) > 1:
+                        # If multiple migration founds, we chose one randomly, but need
+                        # to alert that it's not very precise.
+                        logger.warning(
+                            "Found multiple migration files matching altered "
+                            "file path %s. Choose (%s, %s) opportunistically.",
+                            line,
+                            migration.app_label,
+                            migration.name,
+                        )
                 else:
+                    app_label, name = split_migration_path(line)
                     logger.info(
                         "Found migration file (%s, %s) "
                         "that is not present in loaded migration.",

tests/fixtures.py

@@ -19,3 +19,5 @@ DATA_MIGRATIONS = "app_data_migrations"
 MAKE_NOT_NULL_WITH_DJANGO_DEFAULT = "app_make_not_null_with_django_default"
 MAKE_NOT_NULL_WITH_LIB_DEFAULT = "app_make_not_null_with_lib_default"
 CREATE_INDEX_EXCLUSIVE = "app_create_index_exclusive"
+CUSTOM_APP_NAME_DIRECTORY = "app_with_custom_name"
+CUSTOM_APP_LABEL = "my_custom_name"

tests/functional/test_migration_linter.py

@@ -34,22 +34,32 @@ class BaseBackwardCompatibilityDetection:
         linter = self._launch_linter(app, commit_id)
         self.assertTrue(linter.has_errors)
         self.assertNotEqual(linter.nb_valid + linter.nb_erroneous, 0)
+        self.assertGreater(linter.nb_total, 0)
 
     def _test_linter_finds_no_errors(self, app=None, commit_id=None):
         linter = self._launch_linter(app, commit_id)
         self.assertFalse(linter.has_errors)
         self.assertNotEqual(linter.nb_valid + linter.nb_erroneous, 0)
+        self.assertGreater(linter.nb_total, 0)
+
+    def _test_linter_linted_no_migration(self, app=None, commit_id=None):
+        linter = self._launch_linter(app, commit_id)
+        self.assertEqual(linter.nb_valid, 0)
+        self.assertEqual(linter.nb_erroneous, 0)
+        self.assertEqual(linter.nb_total, 0)
 
     def _launch_linter(self, app=None, commit_id=None):
-        linter = MigrationLinter(
+        linter = self._get_linter()
+        linter.lint_all_migrations(app_label=app, git_commit_id=commit_id)
+        return linter
+
+    def _get_linter(self):
+        return MigrationLinter(
             self.test_project_path,
             database=self.database,
             no_cache=True,
         )
-        linter.lint_all_migrations(app_label=app, git_commit_id=commit_id)
-        return linter
 
-    # *** Tests ***
     def test_create_table_with_not_null_column(self):
         app = fixtures.CREATE_TABLE_WITH_NOT_NULL_COLUMN
         self._test_linter_finds_no_errors(app)
@@ -121,6 +131,22 @@ class BaseBackwardCompatibilityDetection:
         with self.assertRaises(ValueError):
             linter.get_sql("app_unique_together", "0003")
 
+    def test_custom_named_app(self):
+        # Folder name is not found.
+        app = fixtures.CUSTOM_APP_NAME_DIRECTORY
+        self._test_linter_linted_no_migration(app)
+
+        # Django app name is found.
+        app = fixtures.CUSTOM_APP_LABEL
+        self._test_linter_finds_no_errors(app)
+
+        # And with git ref:
+        app = fixtures.CUSTOM_APP_NAME_DIRECTORY
+        self._test_linter_linted_no_migration(app, commit_id="v0.1.4")
+
+        app = fixtures.CUSTOM_APP_LABEL
+        self._test_linter_finds_no_errors(app, commit_id="v0.1.4")
+
 
 class SqliteBackwardCompatibilityDetectionTestCase(
     BaseBackwardCompatibilityDetection, unittest.TestCase

tests/test_project/app_with_custom_name/apps.py

@@ -0,0 +1,8 @@
+from __future__ import annotations
+
+from django.apps import AppConfig
+
+
+class DefaultConfig(AppConfig):
+    name = "tests.test_project.app_with_custom_name"
+    label = "my_custom_name"

tests/test_project/app_with_custom_name/migrations/0001_initial.py

@@ -0,0 +1,30 @@
+# Generated by Django 2.2 on 2019-07-29 21:21
+
+from __future__ import annotations
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+    initial = True
+
+    dependencies = []
+
+    operations = [
+        migrations.CreateModel(
+            name="A",
+            fields=[
+                (
+                    "id",
+                    models.AutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                ("int_field", models.IntegerField()),
+                ("char_field", models.CharField(max_length=255)),
+            ],
+        )
+    ]

tests/test_project/app_with_custom_name/models.py

@@ -0,0 +1,8 @@
+from __future__ import annotations
+
+from django.db import models
+
+
+class A(models.Model):
+    int_field = models.IntegerField()
+    char_field = models.CharField(max_length=255)

tests/test_project/settings.py

@@ -59,6 +59,7 @@ INSTALLED_APPS = [
     "tests.test_project.app_make_not_null_with_django_default",
     "tests.test_project.app_make_not_null_with_lib_default",
     "tests.test_project.app_create_index_exclusive",
+    "tests.test_project.app_with_custom_name.apps.DefaultConfig",
 ]
 
 if django.VERSION[0] >= 5: