hg debuginstall
  $ hg debuginstall
  checking encoding (ascii)...
  checking Python executable (*) (glob)
  checking Python version (2.*) (glob)
  checking Python lib (*lib*)... (glob)
  checking installed modules (*mercurial)... (glob)
  checking templates (*mercurial?templates)... (glob)
  checking commit editor...
  checking username...
  no problems detected

hg debuginstall with no username
  $ HGUSER= hg debuginstall
  checking encoding (ascii)...
  checking Python executable (*) (glob)
  checking Python version (2.*) (glob)
  checking Python lib (*lib*)... (glob)
  checking installed modules (*mercurial)... (glob)
  checking templates (*mercurial?templates)... (glob)
  checking commit editor...
  checking username...
   no username supplied
   (specify a username in your configuration file)
  1 problems detected, please check your install!
  [1]

path variables are expanded (~ is the same as $TESTTMP)
  $ mkdir tools
  $ touch tools/testeditor.exe
#if execbit
  $ chmod 755 tools/testeditor.exe
#endif
  $ hg debuginstall --config ui.editor=~/tools/testeditor.exe
  checking encoding (ascii)...
  checking Python executable (*) (glob)
  checking Python version (*) (glob)
  checking Python lib (*lib*)... (glob)
  checking installed modules (*mercurial)... (glob)
  checking templates (*mercurial?templates)... (glob)
  checking commit editor...
  checking username...
  no problems detected

  $ cat >> wixxml.py << EOF
  > import os, subprocess, sys
  > import xml.etree.ElementTree as ET
  > 
  > # MSYS mangles the path if it expands $TESTDIR
  > testdir = os.environ['TESTDIR']
  > ns = {'wix' : 'http://schemas.microsoft.com/wix/2006/wi'}
  > 
  > def directory(node, relpath):
  >     '''generator of files in the xml node, rooted at relpath'''
  >     dirs = node.findall('./wix:Directory', ns)
  > 
  >     for d in dirs:
  >         for subfile in directory(d, relpath + d.attrib['Name'] + '/'):
  >             yield subfile
  > 
  >     files = node.findall('./wix:Component/wix:File', ns)
  > 
  >     for f in files:
  >         yield relpath + f.attrib['Name']
  > 
  > def hgdirectory(relpath):
  >     '''generator of tracked files, rooted at relpath'''
  >     hgdir = "%s/../mercurial" % (testdir)
  >     args = ['hg', '--cwd', hgdir, 'files', '--rev', '.', relpath]
  >     proc = subprocess.Popen(args, stdout=subprocess.PIPE,
  >                             stderr=subprocess.PIPE)
  >     output = proc.communicate()[0]
  > 
  >     slash = '/'
  >     for line in output.splitlines():
  >         if os.name == 'nt':
  >             yield line.replace(os.sep, slash)
  >         else:
  >             yield line
  > 
  > tracked = [f for f in hgdirectory(sys.argv[1])]
  > 
  > xml = ET.parse("%s/../contrib/wix/%s.wxs" % (testdir, sys.argv[1]))
  > root = xml.getroot()
  > dir = root.find('.//wix:DirectoryRef', ns)
  > 
  > installed = [f for f in directory(dir, '')]
  > 
  > print('Not installed:')
  > for f in sorted(set(tracked) - set(installed)):
  >     print('  %s' % f)
  > 
  > print('Not tracked:')
  > for f in sorted(set(installed) - set(tracked)):
  >     print('  %s' % f)
  > EOF

  $ python wixxml.py help
  Not installed:
    help/common.txt
    help/hg.1.txt
    help/hgignore.5.txt
    help/hgrc.5.txt
    help/internals/bundles.txt
    help/internals/changegroups.txt
  Not tracked:

  $ python wixxml.py templates
  Not installed:
    templates/map-cmdline.status
  Not tracked: