Code2Vec Features Model can not be loaded

[kafkasl]

Issue Trying to load a Code2Vec_Features modelforge model does not work (traceback of the error at the end).

Model data

Code2Vec_Features:
value2index:  dict[string] = int
path2index:  dict[tuple] = int
value2freq:  dict[string] = int
path2freq:  dict[tuple] = int
path_contexts: list[ (string1, list1), (string2, list2) ...]

The model seems to be correctly saved, i.e., I've checked that all parameters of the tree passed to the asdf write asdf.AsdfFile(final_tree).write_to(file) are immutable (dictionary with tuples as keys).

What I've tried just in case

• Turn path_contexts list into tuples just in case.
• Remove empty elements (such as whitspaces or similars).

Error origin

The error appears in yaml/constructor.py file. The reason appears to be that the generator function construct_yaml_seq yields an empty list which is then associated to a node and then used as key. I don't know if this is a yaml bug or expected behavior. I'm assuming that it is not a bug but further debugging to find the reason requires more detailed inspection of the yaml setup etc... which I do not have time to do now.

Traceback

Traceback (most recent call last):
  File "/home/hydra/projects/code2vec/scripts/../src/__main__.py", line 68, in <module>
    sys.exit(main())
  File "/home/hydra/projects/code2vec/scripts/../src/__main__.py", line 64, in main
    return handler(args)
  File "/usr/local/lib/python3.6/dist-packages/sourced/ml/utils/engine.py", line 87, in wrapped_pause
    return func(cmdline_args, *args, **kwargs)
  File "/home/hydra/projects/code2vec/src/cmd/code2vec_train.py", line 18, in code2vec_train
    model = Code2VecFeatures().load(args.input)
  File "/usr/local/lib/python3.6/dist-packages/modelforge-0.6.1-py3.6.egg/modelforge/model.py", line 106, in load
    with asdf.open(source) as model:
  File "/usr/local/lib/python3.6/dist-packages/asdf/asdf.py", line 766, in open
    ignore_missing_extensions=ignore_missing_extensions)
  File "/usr/local/lib/python3.6/dist-packages/asdf/asdf.py", line 678, in _open_impl
    ignore_missing_extensions=ignore_missing_extensions)
  File "/usr/local/lib/python3.6/dist-packages/asdf/asdf.py", line 613, in _open_asdf
    tree = yamlutil.load_tree(reader, self, self._ignore_version_mismatch)
  File "/usr/local/lib/python3.6/dist-packages/asdf/yamlutil.py", line 295, in load_tree
    return yaml.load(stream, Loader=AsdfLoaderTmp)
  File "/usr/local/lib/python3.6/dist-packages/yaml/__init__.py", line 72, in load
    return loader.get_single_data()
  File "/usr/local/lib/python3.6/dist-packages/yaml/constructor.py", line 37, in get_single_data
    return self.construct_document(node)
  File "/usr/local/lib/python3.6/dist-packages/yaml/constructor.py", line 46, in construct_document
    for dummy in generator:
  File "/usr/local/lib/python3.6/dist-packages/yaml/constructor.py", line 398, in construct_yaml_map
    value = self.construct_mapping(node)
  File "/usr/local/lib/python3.6/dist-packages/yaml/constructor.py", line 204, in construct_mapping
    return super().construct_mapping(node, deep=deep)
  File "/usr/local/lib/python3.6/dist-packages/yaml/constructor.py", line 128, in construct_mapping
    "found unhashable key", key_node.start_mark)
yaml.constructor.ConstructorError: while constructing a mapping
  in "<file>", line 18, column 3
found unhashable key
  in "<file>", line 18, column 5

[r0mainK]

Fixed.