shortest: extract function for checking if a prefix is a revnum
Much of isvalid() was about testing if a prefix is a valid revnum. I
want to reuse that soon, so let's move it out.
There is no significant slowdown from the function call overhead.
Differential Revision: https://phab.mercurial-scm.org/D3460
{header}
<title>{repo|escape}: diff {file|escape}</title>
<link rel="alternate" type="application/atom+xml" href="{url|urlescape}atom-log" title="Atom feed for {repo|escape}"/>
<link rel="alternate" type="application/rss+xml" href="{url|urlescape}rss-log" title="RSS feed for {repo|escape}"/>
</head>
<body>
<div id="container">
<div class="page-header">
<h1 class="breadcrumb"><a href="/">Mercurial</a> {pathdef%breadcrumb} / file diff</h1>
{searchform}
<ul class="page-nav">
<li><a href="{url|urlescape}summary{sessionvars%urlparameter}">summary</a></li>
<li><a href="{url|urlescape}shortlog{sessionvars%urlparameter}">shortlog</a></li>
<li><a href="{url|urlescape}log{sessionvars%urlparameter}">changelog</a></li>
<li><a href="{url|urlescape}graph/{symrev}{sessionvars%urlparameter}">graph</a></li>
<li><a href="{url|urlescape}tags{sessionvars%urlparameter}">tags</a></li>
<li><a href="{url|urlescape}bookmarks{sessionvars%urlparameter}">bookmarks</a></li>
<li><a href="{url|urlescape}branches{sessionvars%urlparameter}">branches</a></li>
<li><a href="{url|urlescape}file/{symrev}{path|urlescape}{sessionvars%urlparameter}">files</a></li>
<li><a href="{url|urlescape}help{sessionvars%urlparameter}">help</a></li>
</ul>
</div>
<ul class="submenu">
<li><a href="{url|urlescape}file/{symrev}/{file|urlescape}{sessionvars%urlparameter}">file</a></li>
<li><a href="{url|urlescape}file/tip/{file|urlescape}{sessionvars%urlparameter}">latest</a></li>
<li><a href="{url|urlescape}log/{symrev}/{file|urlescape}{sessionvars%urlparameter}">revisions</a></li>
<li><a href="{url|urlescape}annotate/{symrev}/{file|urlescape}{sessionvars%urlparameter}">annotate</a></li>
<li class="current">diff</li>
<li><a href="{url|urlescape}comparison/{symrev}/{file|urlescape}{sessionvars%urlparameter}">comparison</a></li>
<li><a href="{url|urlescape}raw-diff/{symrev}/{file|urlescape}">raw</a></li>
</ul>
<h2 class="no-link no-border">diff: {file|escape}</h2>
<h3 class="changeset">{file|escape}</h3>
<dl class="overview">
{branch%filerevbranch}
<dt>changeset {rev}</dt>
<dd><a href="{url|urlescape}rev/{node|short}{sessionvars%urlparameter}">{node|short}</a></dd>
{parent%filediffparent}
{child%filediffchild}
</dl>
<div class="diff diffblocks">
{diff}
</div>
{footer}