revset: allow rev(-1) to indicate null revision (BC)
This can simplify the conversion from numeric revision to string. Without it,
we have to handle -1 specially because repo['-1'] != repo[-1].
The -1 revision is not officially documented, but this change makes sense
assuming that "rev(%d)" exists for scripting or third-party tools.
#!/usr/bin/env python
__doc__ = """Same as `echo a >> b`, but ensures a changed mtime of b.
Without this svn will not detect workspace changes."""
import sys, os
text = sys.argv[1]
fname = sys.argv[2]
f = open(fname, "ab")
try:
before = os.fstat(f.fileno()).st_mtime
f.write(text)
f.write("\n")
finally:
f.close()
inc = 1
now = os.stat(fname).st_mtime
while now == before:
t = now + inc
inc += 1
os.utime(fname, (t, t))
now = os.stat(fname).st_mtime