debugshell: disable demand importer when importing debugger
For reasons I can't explain (but likely have something to do with a
combination of __import__ inferring default values for arguments and
the demand importer mechanism further assuming defaults), the demand
importer isn't playing well with IPython. Without this patch, we get
a failure "ValueError: Attempted relative import in non-package" when
attempting to import "IPython." The stack has numerous demandimport
calls on it and adding "IPython" to the exclude list in demandimport
isn't enough to make the problem go away, which means the issue is
likely somewhere in the bowells of IPython. It's easier to just disable
the demand importer when importing the debugger.
#!/usr/bin/env python
#
# Dumps output generated by Mercurial's command server in a formatted style to a
# given file or stderr if '-' is specified. Output is also written in its raw
# format to stdout.
#
# $ ./hg serve --cmds pipe | ./contrib/debugcmdserver.py -
# o, 52 -> 'capabilities: getencoding runcommand\nencoding: UTF-8'
import sys, struct
if len(sys.argv) != 2:
print 'usage: debugcmdserver.py FILE'
sys.exit(1)
outputfmt = '>cI'
outputfmtsize = struct.calcsize(outputfmt)
if sys.argv[1] == '-':
log = sys.stderr
else:
log = open(sys.argv[1], 'a')
def read(size):
data = sys.stdin.read(size)
if not data:
raise EOFError
sys.stdout.write(data)
sys.stdout.flush()
return data
try:
while True:
header = read(outputfmtsize)
channel, length = struct.unpack(outputfmt, header)
log.write('%s, %-4d' % (channel, length))
if channel in 'IL':
log.write(' -> waiting for input\n')
else:
data = read(length)
log.write(' -> %r\n' % data)
log.flush()
except EOFError:
pass
finally:
if log != sys.stderr:
log.close()