nodemap: keep track of the ondisk id of nodemap blocks
If we are to incrementally update the files, we need to keep some details about
the data we read.
Differential Revision: https://phab.mercurial-scm.org/D7883
[tool.black]
line-length = 80
exclude = '''
build/
| wheelhouse/
| dist/
| packages/
| \.hg/
| \.mypy_cache/
| \.venv/
| mercurial/thirdparty/
'''
skip-string-normalization = true
quiet = true