convert: add a mode where mercurial_sink skips empty revisions.
The getchanges function of some converter_source classes can return
some false positives. I.e. they sometimes claim that a file "foo"
was changed in some revision, even though its contents are still the
same.
convert_svn is particularly bad, but I think this can also happen with
convert_cvs and, at least in theory, with mercurial_source.
For regular conversions this is not really a problem - as long as
getfile returns the right contents, we'll get a converted revision
with the right contents. But when we use --filemap, this could lead
to superfluous revisions being converted.
Instead of fixing every converter_source, I decided to change
mercurial_sink to work around this problem.
When --filemap is used, we're interested only in revisions that touch
some specific files. If a revision doesn't change any of these files,
then we're not interested in it (at least for revisions with a single
parent; merges are special).
For mercurial_sink, we abuse this property and rollback a commit if
the manifest text hasn't changed. This avoids duplicating the logic
from localrepo.filecommit to detect unchanged files.
#header#
<title>#repo|escape#: Summary</title>
<link rel="alternate" type="application/atom+xml"
href="{url}atom-log" title="Atom feed for #repo|escape#">
<link rel="alternate" type="application/rss+xml"
href="{url}rss-log" title="RSS feed for #repo|escape#">
</head>
<body>
<div class="page_header">
<a href="http://www.selenic.com/mercurial/" title="Mercurial"><div style="float:right;">Mercurial</div></a><a href="{url}summary{sessionvars%urlparameter}">#repo|escape#</a> / summary
<form action="{url}log">
{sessionvars%hiddenformentry}
<div class="search">
<input type="text" name="rev" />
</div>
</form>
</div>
<div class="page_nav">
summary |
<a href="{url}shortlog{sessionvars%urlparameter}">shortlog</a> |
<a href="{url}log{sessionvars%urlparameter}">changelog</a> |
<a href="{url}tags{sessionvars%urlparameter}">tags</a> |
<a href="{url}file/#node|short#{sessionvars%urlparameter}">manifest</a>#archives%archiveentry#
<br/>
</div>
<div class="title"> </div>
<table cellspacing="0">
<tr><td>description</td><td>#desc#</td></tr>
<tr><td>owner</td><td>#owner|escape#</td></tr>
<tr><td>last change</td><td>#lastchange|rfc822date#</td></tr>
</table>
<div><a class="title" href="{url}shortlog{sessionvars%urlparameter}">changes</a></div>
<table cellspacing="0">
#shortlog#
<tr class="light"><td colspan="4"><a class="list" href="{url}shortlog{sessionvars%urlparameter}">...</a></td></tr>
</table>
<div><a class="title" href="{url}tags{sessionvars%urlparameter}">tags</a></div>
<table cellspacing="0">
#tags#
<tr class="light"><td colspan="3"><a class="list" href="{url}tags{sessionvars%urlparameter}">...</a></td></tr>
</table>
<div><a class="title" href="#">branches</a></div>
<table cellspacing="0">
{branches%branchentry}
<tr class="light">
<td colspan="4"><a class="list" href="#">...</a></td>
</tr>
</table>
#footer#