Fix backwards compatibility of vocab serialization #591
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
(Hopefully) fixes the issue mentioned in #531, after the PR was merged.
Previous instances of "Vocab" didn't have the "unk_index" attribute, which the deserialization wrongly assumes will be present. This is causing issues when loading models stored with previous versions of torchtext. I added a bandaid fix as well as a test checking whether loading works on a mocked older version of the Vocab instance.
@francoishernandez I would appreciate if you can test the patch once it's merged.