[pyyaml 3.13] TypeError while dumping lambda in Python 3

[NiklasRosenstein]

import yaml
print(yaml.dump(lambda: None))

This fails with a TypeError in Python 3 (not in Python 2).

[...]
  File "/Users/nrosenstein/Projects/.venv/lib/python3.7/site-packages/yaml/emitter.py", line 228, in expect_document_root
    self.expect_node(root=True)
  File "/Users/nrosenstein/Projects/.venv/lib/python3.7/site-packages/yaml/emitter.py", line 242, in expect_node
    self.process_tag()
  File "/Users/nrosenstein/Projects/.venv/lib/python3.7/site-packages/yaml/emitter.py", line 489, in process_tag
    self.prepared_tag = self.prepare_tag(tag)
  File "/Users/nrosenstein/Projects/.venv/lib/python3.7/site-packages/yaml/emitter.py", line 607, in prepare_tag
    for ch in data:
TypeError: ord() expected string of length 1, but int found

For reference:

pyyaml/lib3/yaml/emitter.py

Lines 569 to 575 in a2d481b

	else:
	if start < end:
	chunks.append(prefix[start:end])
	start = end = end+1
	data = ch.encode('utf-8')
	for ch in data:
	chunks.append('%%%02X' % ord(ch))

On a side note, I don't know how the line numbers don't match. I have PyYAML 3.13 installed and this references the commit on the 3.13 tag.

str.encode() returns a bytes object in Python 3, which in turn yields integers and no substrings when iterated over, leading ord() to fail.

[perlpunk]

Thanks, this should actually be fixed by #129

[fersarr]

We are being hit by this too. I guess this explains the issue https://stackoverflow.com/questions/19897209/troubleshooting-typeerror-ord-expected-string-of-length-1-but-int-found

Any estimates on when #129 will be merged?

[perlpunk]

This was fixed in PyYAML 5.1 with #129