view tests/filtertraceback.py @ 43786:421ea5772039

copies: split the combination of the copies mapping in its own function

In some case, this part take up to 95% of the copy tracing that take about a
hundred second. This poor performance comes from the fact we keep duplciating
and merging dictionary that are mostly similar.

I want to experiment with smarter native code to do this, so I need to isolate
the function first.

#!/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='')