#1607951: Make mailbox.Maildir re-read the directories less frequently.

This is done by recording the current time -1sec, and not re-reading unless
the directory mod. times are >= the recorded time.

1 files changed, 31 insertions, 0 deletions

diff --git a/Lib/test/test_mailbox.py b/Lib/test/test_mailbox.py
index 714bf25..6342676 100644
--- a/Lib/test/test_mailbox.py
+++ b/Lib/test/test_mailbox.py
@@ -747,6 +747,37 @@ class TestMaildir(TestMailbox):
         perms = st.st_mode
         self.assertFalse((perms & 0111)) # Execute bits should all be off.
 
+    def test_reread(self):
+        # Wait for 2 seconds
+        time.sleep(2)
+
+        # Initially, the mailbox has not been read and the time is null.
+        assert getattr(self._box, '_last_read', None) is None
+
+        # Refresh mailbox; the times should now be set to something.
+        self._box._refresh()
+        assert getattr(self._box, '_last_read', None) is not None
+
+        # Try calling _refresh() again; the modification times shouldn't have
+        # changed, so the mailbox should not be re-reading.  Re-reading causes
+        # the ._toc attribute to be assigned a new dictionary object, so
+        # we'll check that the ._toc attribute isn't a different object.
+        orig_toc = self._box._toc
+        def refreshed():
+            return self._box._toc is not orig_toc
+
+        time.sleep(1)         # Wait 1sec to ensure time.time()'s value changes
+        self._box._refresh()
+        assert not refreshed()
+
+        # Now, write something into cur and remove it.  This changes
+        # the mtime and should cause a re-read.
+        filename = os.path.join(self._path, 'cur', 'stray-file')
+        f = open(filename, 'w')
+        f.close()
+        os.unlink(filename)
+        self._box._refresh()
+        assert refreshed()
 
 class _TestMboxMMDF(TestMailbox):