cmdutil: return a dummy, closable file object if it cannot be duped
If the ui I/O descriptors aren't real descriptors, they cannot be duped.
Instead, we return a wrapper object that behaves the same, and
can be closed (by overriding close and doing nothing).
Mercurial's internal web server, hgweb, can serve either a single
repository, or a collection of them. In the latter case, a special
configuration file can be used to specify the repository paths to use
and global web configuration options.
This file uses the same syntax as other Mercurial configuration files,
but only the following sections are recognized:
- web
- paths
- collections
The ``web`` section can specify all the settings described in the web
section of the hgrc(5) documentation. See :hg:`help config` for
information on where to find the manual page.
The ``paths`` section provides mappings of physical repository
paths to virtual ones. For instance::
[paths]
projects/a = /foo/bar
projects/b = /baz/quux
web/root = /real/root/*
/ = /real/root2/*
virtual/root2 = /real/root2/**
- The first two entries make two repositories in different directories
appear under the same directory in the web interface
- The third entry maps every Mercurial repository found in '/real/root'
into 'web/root'. This format is preferred over the [collections] one,
since using absolute paths as configuration keys is not supported on every
platform (especially on Windows).
- The fourth entry is a special case mapping all repositories in
'/real/root2' in the root of the virtual directory.
- The fifth entry recursively finds all repositories under the real
root, and maps their relative paths under the virtual root.
The ``collections`` section provides mappings of trees of physical
repositories paths to virtual ones, though the paths syntax is generally
preferred. For instance::
[collections]
/foo = /foo
Here, the left side will be stripped off all repositories found in the
right side. Thus ``/foo/bar`` and ``foo/quux/baz`` will be listed as
``bar`` and ``quux/baz`` respectively.