hgweb: do not import uuid immediately to avoid its side effect...
hgweb: do not import uuid immediately to avoid its side effect
With hgdemandimport disabled (chg's case), `import uuid` has an immediate
side effect calling `ctypes.util.find_library` trying to locate the
`libuuid` library. This happens at `import` time before `dispatch.run()`.
The call trace is like:
File "hg/hg", line 54, in <module>
from mercurial import (
File "hg/mercurial/dispatch.py", line 24, in <module>
from . import (
File "hg/mercurial/commands.py", line 23, in <module>
from . import (
File "hg/mercurial/help.py", line 33, in <module>
from .hgweb import (
File "hg/mercurial/hgweb/__init__.py", line 20, in <module>
from . import (
File "hg/mercurial/hgweb/hgweb_mod.py", line 14, in <module>
from .common import (
File "hg/mercurial/hgweb/common.py", line 15, in <module>
import uuid
File "/usr/lib64/python2.7/uuid.py", line 404, in <module>
lib = ctypes.CDLL(ctypes.util.find_library(libname))
The problem is, `ctypes.util.find_library` will execute
`sh -c '/sbin/ldconfig -p 2>/dev/null'` on Python <= 2.7.12. The output of
`sh` may pollute the terminal:
shell-init: error retrieving current directory: getcwd: cannot access
parent directories: No such file or directory
This patch moves `import uuid` so its side-effect can only happen after the
cwd check in `dispatch._getlocal`. Therefore the terminal won't be
polluted by importing `uuid`.
Differential Revision:
https://phab.mercurial-scm.org/D1024
