🐛 Fix "list" to not explode when no migrations directories are given

dbmigrator/tests/test_cli.py

@@ -10,16 +10,22 @@
 import unittest
 
 import pkg_resources
+import psycopg2
 
-from .testing import captured_output
+from . import testing
 
 
 class MainTestCase(unittest.TestCase):
+    def tearDown(self):
+        with psycopg2.connect(testing.db_connection_string) as db_conn:
+            with db_conn.cursor() as cursor:
+                cursor.execute('DROP TABLE IF EXISTS schema_migrations')
+
     def test_version(self):
         from ..cli import main
 
         version = pkg_resources.get_distribution('db-migrator').version
-        with captured_output() as (out, err):
+        with testing.captured_output() as (out, err):
             self.assertRaises(SystemExit, main, ['-V'])
 
         stdout = out.getvalue()
@@ -30,3 +36,21 @@ def test_version(self):
         else:
             self.assertEqual(stdout, '')
             self.assertEqual(stderr.strip(), version)
+
+    def test_list_no_migrations_directory(self):
+        from ..cli import main
+
+        cmd = ['--db-connection-string', testing.db_connection_string]
+        main(cmd + ['init'])
+        with testing.captured_output() as (out, err):
+            main(cmd + ['list'])
+
+        stdout = out.getvalue()
+        stderr = err.getvalue()
+
+        self.assertEqual(stdout, """\
+name                      | is applied | date applied
+----------------------------------------------------------------------\n""")
+        self.assertEqual(stderr, """\
+context undefined, using current directory name "['db-migrator']"
+migrations directory undefined\n""")

dbmigrator/tests/test_utils.py

@@ -147,6 +147,13 @@ def test_get_migrations(self):
              ('20160228210326', 'initial_data'),
              ('20160228212456', 'cool_stuff')])
 
+    def test_get_migrations_no_migrations_directories(self):
+        from ..utils import get_migrations
+
+        migrations = get_migrations([])
+
+        self.assertEqual(list(migrations), [])
+
     def test_get_pending_migrations(self):
         from ..utils import get_pending_migrations
 

dbmigrator/utils.py

@@ -94,7 +94,7 @@ def get_migrations(migration_directories, import_modules=False, reverse=False):
     paths = [os.path.join(md, '*.py') for md in migration_directories]
     python_files = functools.reduce(
         lambda a, b: a + b,
-        [glob.glob(path) for path in paths])
+        [glob.glob(path) for path in paths], [])
     for path in sorted(python_files,
                        key=lambda path: os.path.basename(path),
                        reverse=reverse):