Validator does not promote integer types across signedness

[t-b]

Related to NeurodataWithoutBorders/pynwb#1321 and https://dandiarchive.slack.com/archives/C011LRNU2F7/p1605978955012100?thread_ts=1605798117.007200&cid=C011LRNU2F7.

The file
HardwareTests-V2-MIES-187d9143.zip validates against the cached spec (2.2.4 core and 1.1.3 hdmf). But fails against the stock schemas of pynwb 1.4.0.

$ python -m pynwb.validate --no-cached-namespace HardwareTests-V2-MIES-187d9143.nwb
Validating HardwareTests-V2-MIES-187d9143.nwb against pynwb namespace information using namespace core.
 - found the following errors:
VectorIndex/description (general/intracellular_ephys/sweep_table/series_index): argument missing
VectorIndex (general/intracellular_ephys/sweep_table/series_index): incorrect type - expected 'uint8', got 'int32'
VectorIndex/description (general/intracellular_ephys/sweep_table/series_index): argument missing
VectorIndex (general/intracellular_ephys/sweep_table/series_index): incorrect type - expected 'uint8', got 'int32'
(base)
thomas@Win10-Thomas-PC MSYS /e/projekte/mies-igor/tools/unit-testing (feature/add-subject-info)
$ python -m pynwb.validate --cached-namespace HardwareTests-V2-MIES-187d9143.nwb
Validating HardwareTests-V2-MIES-187d9143.nwb against cached namespace information using namespace ndx-mies.
 - no errors found.
(base)

The validation error is incorrect as every uint8 can be represented as int32.

Edit: It might be enough to throw a couple of new values into

hdmf/src/hdmf/validate/validator.py

Lines 21 to 40 in fab5660

	__additional = {
	'float': ['double'],
	'int8': ['short', 'int', 'long'],
	'short': ['int', 'long'],
	'int': ['long'],
	'uint8': ['uint16', 'uint32', 'uint64'],
	'uint16': ['uint32', 'uint64'],
	'uint32': ['uint64'],
	'utf': ['ascii']
	}
	# if the spec dtype is a key in __allowable, then all types in __allowable[key] are valid
	__allowable = dict()
	for dt, dt_syn in __synonyms.items():
	allow = copy(dt_syn)
	if dt in __additional:
	for addl in __additional[dt]:
	allow.extend(__synonyms[addl])
	for syn in dt_syn:
	__allowable[syn] = allow

.