TypeError: data must be None or an array name (string), not b'NJet'

[jyn514]

Ran into this while doing the problems for GSOC. I think the problem is that the library is not compatible with Python3 unicode strings, but I may be wrong.

Traceback

>>> import oamap.source.root, uproot, functional
>>> events = uproot.open("http://scikit-hep.org/uproot/examples/HZZ.root")["events"].oamap() 
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/joshua/.local/lib/python3.6/site-packages/oamap/source/root.py", line 187, in __call__
    generator = self.schema.generator()
  File "/home/joshua/.local/lib/python3.6/site-packages/oamap/source/root.py", line 184, in schema
    return oamap.schema.List(recurse(self.tree), starts="", stops="")
  File "/home/joshua/.local/lib/python3.6/site-packages/oamap/source/root.py", line 138, in recurse
    x = frominterp(name, branch, uproot.interp.auto.interpret(branch))
  File "/home/joshua/.local/lib/python3.6/site-packages/oamap/source/root.py", line 100, in frominterp
    return oamap.schema.Primitive(interpretation.todtype, data=name)
  File "/home/joshua/.local/lib/python3.6/site-packages/oamap/schema.py", line 346, in __init__
    self.data = data
  File "/home/joshua/.local/lib/python3.6/site-packages/oamap/schema.py", line 418, in data
    raise TypeError("data must be None or an array name (string), not {0}".format(repr(value)))
TypeError: data must be None or an array name (string), not b'NJet'

[jpivarski]

That's right. Another GSoC student ran into the same thing. uproot branch names are bytes (because ROOT files have no encoding) and OAMap hasn't been made aware of that.

It is a real bug, but for now just use Python 2. (Sorry!)

[jyn514]

Tried changing basestring = str to basestring = (bytes, str), but then I got TypeError: a bytes-like object is required, not 'str'. Going to run if isinstance(input, str): str = input.encode() on all the relevant functions to keep python3 compat.

[jpivarski]

No longer relevant; that part of the code is gone and will be rewritten (with better Python 3 hygene in mind!).