blob: 6e7af242126833d287d39977bb9abdf0af78c24b [file] [log] [blame]
"""Control of and utilities for debugging."""
import os
# When debugging, it can be helpful to force some options, especially when
# debugging the configuration mechanisms you usually use to control debugging!
# This is a list of forced debugging options.
FORCED_DEBUG = []
class DebugControl(object):
"""Control and output for debugging."""
def __init__(self, options, output):
"""Configure the options and output file for debugging."""
self.options = options
self.output = output
def should(self, option):
"""Decide whether to output debug information in category `option`."""
return (option in self.options or option in FORCED_DEBUG)
def write(self, msg):
"""Write a line of debug output."""
if self.should('pid'):
msg = "pid %5d: %s" % (os.getpid(), msg)
self.output.write(msg+"\n")
self.output.flush()
def write_formatted_info(self, info):
"""Write a sequence of (label,data) pairs nicely."""
for line in info_formatter(info):
self.write(" %s" % line)
def info_formatter(info):
"""Produce a sequence of formatted lines from info.
`info` is a sequence of pairs (label, data). The produced lines are
nicely formatted, ready to print.
"""
label_len = max(len(l) for l, _d in info)
for label, data in info:
if data == []:
data = "-none-"
if isinstance(data, (list, set, tuple)):
prefix = "%*s:" % (label_len, label)
for e in data:
yield "%*s %s" % (label_len+1, prefix, e)
prefix = ""
else:
yield "%*s: %s" % (label_len, label, data)