state: add workaround for VACUUM bug on python 3.6 (#1315)

Fixes #1314

Signed-off-by: Ruslan Kuprieiev <[email protected]>

dvc/state.py

@@ -190,6 +190,12 @@ class State(object):
                 else:
                     raise
 
+    def _vacuum(self):
+        # NOTE: see https://bugs.python.org/issue28518
+        self.db.isolation_level = None
+        self._execute("VACUUM")
+        self.db.isolation_level = ''
+
     def dump(self):
         assert self.db is not None
 
@@ -213,7 +219,7 @@ class State(object):
                                      self.STATE_TABLE,
                                      delete))
 
-            self._execute("VACUUM")
+            self._vacuum()
 
             cmd = "SELECT COUNT(*) FROM {}"
 

tests/test_state.py

@@ -5,6 +5,7 @@ import time
 from dvc.system import System
 from dvc.state import State
 from dvc.utils import file_md5
+from dvc.main import main
 
 from tests.basic_env import TestDvc
 
@@ -39,3 +40,20 @@ class TestState(TestDvc):
 
             entry_md5 = state.update(path)
             self.assertEqual(entry_md5, md5)
+
+
+class TestStateOverflow(TestDvc):
+    def test(self):
+        # NOTE: trying to add more entries than state can handle,
+        # to see if it will clean up and vacuum successfully
+        ret = main(['config', 'state.row_limit', '10'])
+        self.assertEqual(ret, 0)
+
+        dname = 'dir'
+        os.mkdir(dname)
+        for i in range(20):
+            with open(os.path.join(dname, str(i)), 'w+') as fobj:
+                fobj.write(str(i))
+
+        ret = main(['add', 'dir'])
+        self.assertEqual(ret, 0)