view tests/heredoctest.py @ 51550:463e63aa547c

stream-clone: disable gc for `_entries_walk` duration

The number of small container created turn Python in a gc-frenzy that seriously
impact performance.

This significantly boost performance. The following number comes from a large
private repository using perf::stream-locked-section:

base-line:   35.04 seconds
prev-change: 24.51 seconds (-30%)
this-change: 20.88 seconds (-40% from baseline; -15% from previous changes)

import sys


def flush():
    sys.stdout.flush()
    sys.stderr.flush()


globalvars = {}
lines = sys.stdin.readlines()
while lines:
    l = lines.pop(0)
    if l.startswith('SALT'):
        print(l[:-1])
    elif l.startswith('>>> '):
        snippet = l[4:]
        while lines and lines[0].startswith('... '):
            l = lines.pop(0)
            snippet += l[4:]
        c = compile(snippet, '<heredoc>', 'single')
        try:
            flush()
            exec(c, globalvars)
            flush()
        except Exception as inst:
            flush()
            print(repr(inst))