ListOffsetArray type tracers (from form) raise exception when printing #2042
Description
Version of Awkward Array
2.0.4
Description and code to reproduce
requires dask_awkward
import dask_awkward as dak
import awkward as ak
form = ak.forms.ListOffsetForm("i64", ak.forms.NumpyForm("float32", inner_shape=(2,)))
tt = dak.typetracer_from_form(form)
print(tt)results in:
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/Users/lgray/miniforge3/envs/coffea-dev/lib/python3.8/site-packages/awkward/highlevel.py", line 1192, in __str__
return awkward._prettyprint.valuestr(self, 1, 80)
File "/Users/lgray/miniforge3/envs/coffea-dev/lib/python3.8/site-packages/awkward/_prettyprint.py", line 232, in valuestr
_, strs = valuestr_horiz(data, limit_cols)
File "/Users/lgray/miniforge3/envs/coffea-dev/lib/python3.8/site-packages/awkward/_prettyprint.py", line 99, in valuestr_horiz
if len(data) == 0:
TypeError: 'UnknownLengthType' object cannot be interpreted as an integer
Strangely, tt.__repr__() executes just fine but when going through tt.__str__() I get the error!
This seems to have some knock-on problems elsewhere in dask_awkward when automatically determining typetracer metadata.