tests/test-hgweb-no-request-uri.t

util: add utility function to skip avoiding file stat ambiguity if EPERM

Now, advancing stat.st_mtime by os.utime() is used to avoid file stat
ambiguity. But according to POSIX specification, utime(2) with an
explicit time information is permitted only for a process with:

  - the effective user ID equal to the user ID of the file, or
  - appropriate privileges

  http://pubs.opengroup.org/onlinepubs/9699919799/functions/utime.html

Therefore, just having group write access to a file causes EPERM at
applying os.utime() on it (e.g. working on the repository shared by
group access permission).

This patch adds class filestat utility function avoidamgig() to avoid
file stat ambiguity but skip it if EPERM.

It is reasonable to always ignore EPERM, because utime(2) causes EPERM
only in the case described above (EACCES is used only for utime(2)
with NULL).

This tests if hgweb and hgwebdir still work if the REQUEST_URI variable is
no longer passed with the request. Instead, SCRIPT_NAME and PATH_INFO
should be used from d74fc8dec2b4 onward to route the request.

  $ hg init repo
  $ cd repo
  $ echo foo > bar
  $ hg add bar
  $ hg commit -m "test"
  $ hg tip
  changeset:   0:61c9426e69fe
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     test
  
  $ cat > request.py <<EOF
  > from __future__ import absolute_import
  > import os
  > import sys
  > from mercurial.hgweb import (
  >     hgweb,
  >     hgwebdir,
  > )
  > from mercurial import (
  >     util,
  > )
  > stringio = util.stringio
  > 
  > errors = stringio()
  > input = stringio()
  > 
  > def startrsp(status, headers):
  >     print '---- STATUS'
  >     print status
  >     print '---- HEADERS'
  >     print [i for i in headers if i[0] != 'ETag']
  >     print '---- DATA'
  >     return output.write
  > 
  > env = {
  >     'wsgi.version': (1, 0),
  >     'wsgi.url_scheme': 'http',
  >     'wsgi.errors': errors,
  >     'wsgi.input': input,
  >     'wsgi.multithread': False,
  >     'wsgi.multiprocess': False,
  >     'wsgi.run_once': False,
  >     'REQUEST_METHOD': 'GET',
  >     'SCRIPT_NAME': '',
  >     'SERVER_NAME': '127.0.0.1',
  >     'SERVER_PORT': os.environ['HGPORT'],
  >     'SERVER_PROTOCOL': 'HTTP/1.0'
  > }
  > 
  > def process(app):
  >     content = app(env, startrsp)
  >     sys.stdout.write(output.getvalue())
  >     sys.stdout.write(''.join(content))
  >     getattr(content, 'close', lambda : None)()
  >     print '---- ERRORS'
  >     print errors.getvalue()
  > 
  > output = stringio()
  > env['PATH_INFO'] = '/'
  > env['QUERY_STRING'] = 'style=atom'
  > process(hgweb('.', name = 'repo'))
  > 
  > output = stringio()
  > env['PATH_INFO'] = '/file/tip/'
  > env['QUERY_STRING'] = 'style=raw'
  > process(hgweb('.', name = 'repo'))
  > 
  > output = stringio()
  > env['PATH_INFO'] = '/'
  > env['QUERY_STRING'] = 'style=raw'
  > process(hgwebdir({'repo': '.'}))
  > 
  > output = stringio()
  > env['PATH_INFO'] = '/repo/file/tip/'
  > env['QUERY_STRING'] = 'style=raw'
  > process(hgwebdir({'repo': '.'}))
  > EOF
  $ python request.py
  ---- STATUS
  200 Script output follows
  ---- HEADERS
  [('Content-Type', 'application/atom+xml; charset=ascii')]
  ---- DATA
  <?xml version="1.0" encoding="ascii"?>
  <feed xmlns="http://www.w3.org/2005/Atom">
   <!-- Changelog -->
   <id>http://127.0.0.1:$HGPORT/</id> (glob)
   <link rel="self" href="http://127.0.0.1:$HGPORT/atom-log"/> (glob)
   <link rel="alternate" href="http://127.0.0.1:$HGPORT/"/> (glob)
   <title>repo Changelog</title>
   <updated>1970-01-01T00:00:00+00:00</updated>
  
   <entry>
    <title>[default] test</title>
    <id>http://127.0.0.1:$HGPORT/#changeset-61c9426e69fef294feed5e2bbfc97d39944a5b1c</id> (glob)
    <link href="http://127.0.0.1:$HGPORT/rev/61c9426e69fe"/> (glob)
    <author>
     <name>test</name>
     <email>&#116;&#101;&#115;&#116;</email>
    </author>
    <updated>1970-01-01T00:00:00+00:00</updated>
    <published>1970-01-01T00:00:00+00:00</published>
    <content type="xhtml">
     <table xmlns="http://www.w3.org/1999/xhtml">
      <tr>
       <th style="text-align:left;">changeset</th>
       <td>61c9426e69fe</td>
      </tr>
      <tr>
       <th style="text-align:left;">branch</th>
       <td>default</td>
      </tr>
      <tr>
       <th style="text-align:left;">bookmark</th>
       <td></td>
      </tr>
      <tr>
       <th style="text-align:left;">tag</th>
       <td>tip</td>
      </tr>
      <tr>
       <th style="text-align:left;">user</th>
       <td>&#116;&#101;&#115;&#116;</td>
      </tr>
      <tr>
       <th style="text-align:left;vertical-align:top;">description</th>
       <td>test</td>
      </tr>
      <tr>
       <th style="text-align:left;vertical-align:top;">files</th>
       <td>bar<br /></td>
      </tr>
     </table>
    </content>
   </entry>
  
  </feed>
  ---- ERRORS
  
  ---- STATUS
  200 Script output follows
  ---- HEADERS
  [('Content-Type', 'text/plain; charset=ascii')]
  ---- DATA
  
  -rw-r--r-- 4 bar
  
  
  ---- ERRORS
  
  ---- STATUS
  200 Script output follows
  ---- HEADERS
  [('Content-Type', 'text/plain; charset=ascii')]
  ---- DATA
  
  /repo/
  
  ---- ERRORS
  
  ---- STATUS
  200 Script output follows
  ---- HEADERS
  [('Content-Type', 'text/plain; charset=ascii')]
  ---- DATA
  
  -rw-r--r-- 4 bar
  
  
  ---- ERRORS
  

  $ cd ..