contrib/hgweb.wsgi

url: refactor util.drop_scheme() and hg.localpath() into url.localpath()

This replaces util.drop_scheme() with url.localpath(), using url.url for
parsing instead of doing it on its own. The function is moved from
util to url to avoid an import cycle.

hg.localpath() is removed in favor of using url.localpath(). This
provides more consistent behavior between "hg clone" and other
commands.

To preserve backwards compatibility, URLs like bundle://../foo still
refer to ../foo, not /foo.

If a URL contains a scheme, percent-encoded entities are decoded. When
there's no scheme, all characters are left untouched.

Comparison of old and new behaviors:

URL                      drop_scheme()   hg.localpath()    url.localpath()
===                      =============   ==============    ===============
file://foo/foo           /foo            foo/foo           /foo
file://localhost:80/foo  /foo            localhost:80/foo  /foo
file://localhost:/foo    /foo            localhost:/foo    /foo
file://localhost/foo     /foo            /foo              /foo
file:///foo              /foo            /foo              /foo
file://foo               (empty string)  foo               /
file:/foo                /foo            /foo              /foo
file:foo                 foo             foo               foo
file:foo%23bar           foo%23bar       foo%23bar         foo#bar
foo%23bar                foo%23bar       foo%23bar         foo%23bar
/foo                     /foo            /foo              /foo

Windows-related paths on Windows:

URL                      drop_scheme()   hg.localpath()    url.localpath()
===                      =============   ==============    ===============
file:///C:/foo           C:/C:/foo       /C:/foo           C:/foo
file:///D:/foo           C:/D:/foo       /D:/foo           D:/foo
file://C:/foo            C:/foo          C:/foo            C:/foo
file://D:/foo            C:/foo          D:/foo            D:/foo
file:////foo/bar         //foo/bar       //foo/bar         //foo/bar
//foo/bar                //foo/bar       //foo/bar         //foo/bar
\\foo\bar                //foo/bar       //foo/bar         \\foo\bar

Windows-related paths on other platforms:

file:///C:/foo           C:/C:/foo       /C:/foo           C:/foo
file:///D:/foo           C:/D:/foo       /D:/foo           D:/foo
file://C:/foo            C:/foo          C:/foo            C:/foo
file://D:/foo            C:/foo          D:/foo            D:/foo
file:////foo/bar         //foo/bar       //foo/bar         //foo/bar
//foo/bar                //foo/bar       //foo/bar         //foo/bar
\\foo\bar                //foo/bar       //foo/bar         \\foo\bar

For more information about file:// URL handling, see:
http://www-archive.mozilla.org/quality/networking/testing/filetests.html

Related issues:

- issue1153: File URIs aren't handled correctly in windows

  This patch should preserve the fix implemented in
  2770d03ae49f. However, it goes a step further and "promotes"
  Windows-style drive letters from being interpreted as host names to
  being part of the path.

- issue2154: Cannot escape '#' in Mercurial URLs (#1172 in THG)

  The fragment is still interpreted as a revision or a branch, even in
  paths to bundles. However, when file: is used, percent-encoded
  entities are decoded, so file:test%23bundle.hg can refer to
  test#bundle.hg ond isk.

# An example WSGI for use with mod_wsgi, edit as necessary
# See http://mercurial.selenic.com/wiki/modwsgi for more information

# Path to repo or hgweb config to serve (see 'hg help hgweb')
config = "/path/to/repo/or/config"

# Uncomment and adjust if Mercurial is not installed system-wide:
#import sys; sys.path.insert(0, "/path/to/python/lib")

# Uncomment to send python tracebacks to the browser if an error occurs:
#import cgitb; cgitb.enable()

# enable demandloading to reduce startup time
from mercurial import demandimport; demandimport.enable()

from mercurial.hgweb import hgweb
application = hgweb(config)