tests/filtertraceback.py

hgcli: add stub PyOxidizer project

Using commit c772a1379c3026314eda1c8ea244b86c0658951d of
PyOxidizer, I ran `pyoxidizer init-rust-project hgcli` to
create a stub Rust project. The only modifications I made from
what that command produced are:

* Update location of pyembed crate to PyOxidizer's Git repository.
* Removed some trailing whitespace from pyoxidizer.bzl
* Added auto-generated Cargo.lock file

Subsequent commits will modify the stub project to Mercurial's
needs.

Differential Revision: https://phab.mercurial-scm.org/D8350

#!/usr/bin/env python

# Filters traceback lines from stdin.

from __future__ import absolute_import, print_function

import sys

state = 'none'

for line in sys.stdin:
    if state == 'none':
        if line.startswith('Traceback '):
            state = 'tb'

    elif state == 'tb':
        if line.startswith('  File '):
            state = 'file'
            continue

        elif not line.startswith(' '):
            state = 'none'

    elif state == 'file':
        # Ignore lines after "  File "
        state = 'tb'
        continue

    print(line, end='')