# HG changeset patch
# User wujek srujek
# Date 1341760622 -7200
# Node ID 1ae119269ddcbf818217a37608518b27a26ae4e2
# Parent  afd75476939e0a229816e6683607fbe5ab222c11
hgweb: side-by-side comparison functionality

Adds new web command to the core, ``comparison``, which enables colorful
side-by-side change display, which for some might be much easier to work with
than the standard line diff output. The idea how to implement comes from the
SonicHq extension.
The web interface gets a new link to call the comparison functionality. It lets
users configure the amount of context lines around change blocks, or to show
full files - check help (also in this changeset) for details and defaults. The
setting in hgrc can be overridden by adding ``context=<value>`` to the request
query string. The comparison creates addressable lines, so as to enable sharing
links to specific lines, just as standard diff does.
Incorporates updates to all web related styles.

Known limitations:
* the column diff is done against the first parent, just as the standard diff
* this change allows examining diffs for single files only (as I am not sure if
  examining the whole changeset in this way would be helpful)
* syntax highlighting of the output changes is not performed (enabling the
  highlight extension has no influence on it)

diff -r afd75476939e -r 1ae119269ddc mercurial/help/config.txt
--- a/mercurial/help/config.txt	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/help/config.txt	Sun Jul 08 17:17:02 2012 +0200
@@ -1377,6 +1377,12 @@
 ``errorlog``
     Where to output the error log. Default is stderr.
 
+``comparisoncontext``
+    Number of lines of context to show in side-by-side file comparison. If
+    negative or the value ``full``, whole files are shown. Default is 5.
+    This setting can be overridden by a ``context`` request parameter to the
+    ``comparison`` command, taking the same values.
+
 ``hidden``
     Whether to hide the repository in the hgwebdir index.
     Default is False.
diff -r afd75476939e -r 1ae119269ddc mercurial/hgweb/webcommands.py
--- a/mercurial/hgweb/webcommands.py	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/hgweb/webcommands.py	Sun Jul 08 17:17:02 2012 +0200
@@ -22,7 +22,7 @@
 __all__ = [
    'log', 'rawfile', 'file', 'changelog', 'shortlog', 'changeset', 'rev',
    'manifest', 'tags', 'bookmarks', 'branches', 'summary', 'filediff', 'diff',
-   'annotate', 'filelog', 'archive', 'static', 'graph', 'help',
+   'comparison', 'annotate', 'filelog', 'archive', 'static', 'graph', 'help',
 ]
 
 def log(web, req, tmpl):
@@ -586,6 +586,31 @@
 
 diff = filediff
 
+def comparison(web, req, tmpl):
+    ctx = webutil.changectx(web.repo, req)
+    path = webutil.cleanpath(web.repo, req.form['file'][0])
+    rename = path in ctx and webutil.renamelink(ctx[path]) or []
+
+    parsecontext = lambda v: v == 'full' and -1 or int(v)
+    if 'context' in req.form:
+        context = parsecontext(req.form['context'][0])
+    else:
+        context = parsecontext(web.config('web', 'comparisoncontext', '5'))
+
+    comparison = webutil.compare(tmpl, ctx, path, context)
+    return tmpl('filecomparison',
+                file=path,
+                node=hex(ctx.node()),
+                rev=ctx.rev(),
+                date=ctx.date(),
+                desc=ctx.description(),
+                author=ctx.user(),
+                rename=rename,
+                branch=webutil.nodebranchnodefault(ctx),
+                parent=webutil.parents(ctx),
+                child=webutil.children(ctx),
+                comparison=comparison)
+
 def annotate(web, req, tmpl):
     fctx = webutil.filectx(web.repo, req)
     f = fctx.path()
diff -r afd75476939e -r 1ae119269ddc mercurial/hgweb/webutil.py
--- a/mercurial/hgweb/webutil.py	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/hgweb/webutil.py	Sun Jul 08 17:17:02 2012 +0200
@@ -6,10 +6,11 @@
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
-import os, copy
+import os, mimetypes, copy
 from mercurial import match, patch, scmutil, error, ui, util
 from mercurial.i18n import _
 from mercurial.node import hex, nullid
+import difflib
 
 def up(p):
     if p[0] != "/":
@@ -220,6 +221,92 @@
     yield tmpl('diffblock', parity=parity.next(), blockno=blockno,
                lines=prettyprintlines(''.join(block), blockno))
 
+def compare(tmpl, ctx, path, context):
+    '''Generator function that provides side-by-side comparison data.'''
+
+    def filelines(f):
+        if util.binary(f.data()):
+            mt = mimetypes.guess_type(f.path())[0]
+            if not mt:
+                mt = 'application/octet-stream'
+            return [_('(binary file %s, hash: %s)') % (mt, hex(f.filenode()))]
+        return f.data().splitlines()
+
+    def compline(type, leftlineno, leftline, rightlineno, rightline):
+        lineid = leftlineno and ("l%s" % leftlineno) or ''
+        lineid += rightlineno and ("r%s" % rightlineno) or ''
+        return tmpl('comparisonline',
+                    type=type,
+                    lineid=lineid,
+                    leftlinenumber="% 6s" % (leftlineno or ''),
+                    leftline=leftline or '',
+                    rightlinenumber="% 6s" % (rightlineno or ''),
+                    rightline=rightline or '')
+
+    def getblock(opcodes):
+        for type, llo, lhi, rlo, rhi in opcodes:
+            len1 = lhi - llo
+            len2 = rhi - rlo
+            count = min(len1, len2)
+            for i in xrange(count):
+                yield compline(type=type,
+                               leftlineno=llo + i + 1,
+                               leftline=leftlines[llo + i],
+                               rightlineno=rlo + i + 1,
+                               rightline=rightlines[rlo + i])
+            if len1 > len2:
+                for i in xrange(llo + count, lhi):
+                    yield compline(type=type,
+                                   leftlineno=i + 1,
+                                   leftline=leftlines[i],
+                                   rightlineno=None,
+                                   rightline=None)
+            elif len2 > len1:
+                for i in xrange(rlo + count, rhi):
+                    yield compline(type=type,
+                                   leftlineno=None,
+                                   leftline=None,
+                                   rightlineno=i + 1,
+                                   rightline=rightlines[i])
+
+    if path in ctx:
+        fctx = ctx[path]
+        rightrev = fctx.filerev()
+        rightnode = fctx.filenode()
+        rightlines = filelines(fctx)
+        parents = fctx.parents()
+        if not parents:
+            leftrev = -1
+            leftnode = nullid
+            leftlines = ()
+        else:
+            pfctx = parents[0]
+            leftrev = pfctx.filerev()
+            leftnode = pfctx.filenode()
+            leftlines = filelines(pfctx)
+    else:
+        rightrev = -1
+        rightnode = nullid
+        rightlines = ()
+        fctx = ctx.parents()[0][path]
+        leftrev = fctx.filerev()
+        leftnode = fctx.filenode()
+        leftlines = filelines(fctx)
+
+    s = difflib.SequenceMatcher(None, leftlines, rightlines)
+    if context < 0:
+        blocks = [tmpl('comparisonblock', lines=getblock(s.get_opcodes()))]
+    else:
+        blocks = (tmpl('comparisonblock', lines=getblock(oc))
+                     for oc in s.get_grouped_opcodes(n=context))
+
+    yield tmpl('comparison',
+               leftrev=leftrev,
+               leftnode=hex(leftnode),
+               rightrev=rightrev,
+               rightnode=hex(rightnode),
+               blocks=blocks)
+
 def diffstatgen(ctx):
     '''Generator function that provides the diffstat data.'''
 
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/coal/map
--- a/mercurial/templates/coal/map	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/templates/coal/map	Sun Jul 08 17:17:02 2012 +0200
@@ -63,6 +63,7 @@
 filerevision = ../paper/filerevision.tmpl
 fileannotate = ../paper/fileannotate.tmpl
 filediff = ../paper/filediff.tmpl
+filecomparison = ../paper/filecomparison.tmpl
 filelog = ../paper/filelog.tmpl
 fileline = '
   <div class="parity{parity} source"><a href="#{lineid}" id="{lineid}">{linenumber}</a> {line|escape}</div>'
@@ -83,6 +84,26 @@
 difflineat = '<a href="#{lineid}" id="{lineid}">{linenumber}</a> <span class="atline">{line|escape}</span>'
 diffline = '<a href="#{lineid}" id="{lineid}">{linenumber}</a> {line|escape}'
 
+comparison = '
+  <table class="bigtable">
+    <thead class="header">
+      <tr>
+        <th>{leftrev}:{leftnode|short}</th>
+        <th>{rightrev}:{rightnode|short}</th>
+      </tr>
+    </thead>
+    {blocks}
+  </table>'
+comparisonblock ='
+  <tbody class="block">
+  {lines}
+  </tbody>'
+comparisonline = '
+  <tr>
+    <td class="source {type}"><a href="#{lineid}" id="{lineid}">{leftlinenumber}</a> {leftline|escape}</td>
+    <td class="source {type}"><a href="#{lineid}" id="{lineid}">{rightlinenumber}</a> {rightline|escape}</td>
+  </tr>'
+
 changelogparent = '
   <tr>
     <th class="parent">parent {rev}:</th>
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/gitweb/fileannotate.tmpl
--- a/mercurial/templates/gitweb/fileannotate.tmpl	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/templates/gitweb/fileannotate.tmpl	Sun Jul 08 17:17:02 2012 +0200
@@ -26,6 +26,7 @@
 <a href="{url}log/{node|short}/{file|urlescape}{sessionvars%urlparameter}">revisions</a> |
 annotate |
 <a href="{url}diff/{node|short}/{file|urlescape}{sessionvars%urlparameter}">diff</a> |
+<a href="{url}comparison/{node|short}/{file|urlescape}{sessionvars%urlparameter}">comparison</a> |
 <a href="{url}raw-annotate/{node|short}/{file|urlescape}">raw</a> |
 <a href="{url}help{sessionvars%urlparameter}">help</a>
 <br/>
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/gitweb/filecomparison.tmpl
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mercurial/templates/gitweb/filecomparison.tmpl	Sun Jul 08 17:17:02 2012 +0200
@@ -0,0 +1,63 @@
+{header}
+<title>{repo|escape}: comparison {file|escape}</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="{logourl}" title="Mercurial" style="float: right;">Mercurial</a><a href="{url}summary{sessionvars%urlparameter}">{repo|escape}</a> / comparison
+</div>
+
+<div class="page_nav">
+<a href="{url}summary{sessionvars%urlparameter}">summary</a> |
+<a href="{url}shortlog{sessionvars%urlparameter}">shortlog</a> |
+<a href="{url}log{sessionvars%urlparameter}">changelog</a> |
+<a href="{url}graph{sessionvars%urlparameter}">graph</a> |
+<a href="{url}tags{sessionvars%urlparameter}">tags</a> |
+<a href="{url}bookmarks{sessionvars%urlparameter}">bookmarks</a> |
+<a href="{url}branches{sessionvars%urlparameter}">branches</a> |
+<a href="{url}file/{node|short}{path|urlescape}{sessionvars%urlparameter}">files</a> |
+<a href="{url}rev/{node|short}{sessionvars%urlparameter}">changeset</a> |
+<a href="{url}file/{node|short}/{file|urlescape}{sessionvars%urlparameter}">file</a> |
+<a href="{url}file/tip/{file|urlescape}{sessionvars%urlparameter}">latest</a> |
+<a href="{url}log/{node|short}/{file|urlescape}{sessionvars%urlparameter}">revisions</a> |
+<a href="{url}annotate/{node|short}/{file|urlescape}{sessionvars%urlparameter}">annotate</a> |
+<a href="{url}diff/{node|short}/{file|urlescape}{sessionvars%urlparameter}">diff</a> |
+comparison |
+<a href="{url}raw-diff/{node|short}/{file|urlescape}">raw</a> |
+<a href="{url}help{sessionvars%urlparameter}">help</a>
+<br/>
+</div>
+
+<div class="title">{file|escape}</div>
+
+<table>
+{branch%filerevbranch}
+<tr>
+ <td>changeset {rev}</td>
+ <td style="font-family:monospace"><a class="list" href="{url}rev/{node|short}{sessionvars%urlparameter}">{node|short}</a></td></tr>
+{parent%filecompparent}
+{child%filecompchild}
+</table>
+
+<div class="list_head"></div>
+
+<div class="page_body">
+
+<div class="legend">
+  <span class="legendinfo equal">equal</span>
+  <span class="legendinfo delete">deleted</span>
+  <span class="legendinfo insert">inserted</span>
+  <span class="legendinfo replace">replaced</span>
+</div>
+
+<div class="comparison">
+{comparison}
+</div>
+
+</div>
+
+{footer}
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/gitweb/filediff.tmpl
--- a/mercurial/templates/gitweb/filediff.tmpl	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/templates/gitweb/filediff.tmpl	Sun Jul 08 17:17:02 2012 +0200
@@ -26,6 +26,7 @@
 <a href="{url}log/{node|short}/{file|urlescape}{sessionvars%urlparameter}">revisions</a> |
 <a href="{url}annotate/{node|short}/{file|urlescape}{sessionvars%urlparameter}">annotate</a> |
 diff |
+<a href="{url}comparison/{node|short}/{file|urlescape}{sessionvars%urlparameter}">comparison</a> |
 <a href="{url}raw-diff/{node|short}/{file|urlescape}">raw</a> |
 <a href="{url}help{sessionvars%urlparameter}">help</a>
 <br/>
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/gitweb/filelog.tmpl
--- a/mercurial/templates/gitweb/filelog.tmpl	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/templates/gitweb/filelog.tmpl	Sun Jul 08 17:17:02 2012 +0200
@@ -23,6 +23,7 @@
 revisions |
 <a href="{url}annotate/{node|short}/{file|urlescape}{sessionvars%urlparameter}">annotate</a> |
 <a href="{url}diff/{node|short}/{file|urlescape}{sessionvars%urlparameter}">diff</a> |
+<a href="{url}comparison/{node|short}/{file|urlescape}{sessionvars%urlparameter}">comparison</a> |
 <a href="{url}rss-log/tip/{file|urlescape}">rss</a> |
 <a href="{url}help{sessionvars%urlparameter}">help</a>
 <br/>
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/gitweb/filerevision.tmpl
--- a/mercurial/templates/gitweb/filerevision.tmpl	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/templates/gitweb/filerevision.tmpl	Sun Jul 08 17:17:02 2012 +0200
@@ -26,6 +26,7 @@
 <a href="{url}log/{node|short}/{file|urlescape}{sessionvars%urlparameter}">revisions</a> |
 <a href="{url}annotate/{node|short}/{file|urlescape}{sessionvars%urlparameter}">annotate</a> |
 <a href="{url}diff/{node|short}/{file|urlescape}{sessionvars%urlparameter}">diff</a> |
+<a href="{url}comparison/{node|short}/{file|urlescape}{sessionvars%urlparameter}">comparison</a> |
 <a href="{url}raw-file/{node|short}/{file|urlescape}">raw</a> |
 <a href="{url}help{sessionvars%urlparameter}">help</a>
 <br/>
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/gitweb/map
--- a/mercurial/templates/gitweb/map	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/templates/gitweb/map	Sun Jul 08 17:17:02 2012 +0200
@@ -26,6 +26,7 @@
       <a href="{url}file/{node|short}/{file|urlescape}{sessionvars%urlparameter}">file</a> |
       <a href="{url}annotate/{node|short}/{file|urlescape}{sessionvars%urlparameter}">annotate</a> |
       <a href="{url}diff/{node|short}/{file|urlescape}{sessionvars%urlparameter}">diff</a> |
+      <a href="{url}comparison/{node|short}/{file|urlescape}{sessionvars%urlparameter}">comparison</a> |
       <a href="{url}log/{node|short}/{file|urlescape}{sessionvars%urlparameter}">revisions</a>
     </td>
   </tr>'
@@ -37,6 +38,7 @@
       file |
       annotate |
       <a href="{url}diff/{node|short}/{file|urlescape}{sessionvars%urlparameter}">diff</a> |
+      <a href="{url}comparison/{node|short}/{file|urlescape}{sessionvars%urlparameter}">comparison</a> |
       <a href="{url}log/{node|short}/{file|urlescape}{sessionvars%urlparameter}">revisions</a>
     </td>
   </tr>'
@@ -81,6 +83,7 @@
 filerevision = filerevision.tmpl
 fileannotate = fileannotate.tmpl
 filediff = filediff.tmpl
+filecomparison = filecomparison.tmpl
 filelog = filelog.tmpl
 fileline = '
   <div style="font-family:monospace" class="parity{parity}">
@@ -99,6 +102,27 @@
 difflineminus = '<span style="color:#cc0000;"><a class="linenr" href="#{lineid}" id="{lineid}">{linenumber}</a> {line|escape}</span>'
 difflineat = '<span style="color:#990099;"><a class="linenr" href="#{lineid}" id="{lineid}">{linenumber}</a> {line|escape}</span>'
 diffline = '<span><a class="linenr" href="#{lineid}" id="{lineid}">{linenumber}</a> {line|escape}</span>'
+
+comparison = '
+  <table style="border-collapse:collapse;">
+    <thead class="header">
+      <tr>
+        <th>{leftrev}:{leftnode|short}</th>
+        <th>{rightrev}:{rightnode|short}</th>
+      </tr>
+    </thead>
+    {blocks}
+  </table>'
+comparisonblock ='
+  <tbody class="block">
+  {lines}
+  </tbody>'
+comparisonline = '
+  <tr style="font-family:monospace">
+    <td class="{type}"><pre><a class="linenr" href="#{lineid}" id="{lineid}">{leftlinenumber}</a> {leftline|escape}</pre></td>
+    <td class="{type}"><pre><a class="linenr" href="#{lineid}" id="{lineid}">{rightlinenumber}</a> {rightline|escape}</pre></td>
+  </tr>'
+
 changelogparent = '
   <tr>
     <th class="parent">parent {rev}:</th>
@@ -203,6 +227,15 @@
       </a>
     </td>
   </tr>'
+filecompparent = '
+  <tr>
+    <td>parent {rev}</td>
+    <td style="font-family:monospace">
+      <a class="list" href="{url}comparison/{node|short}/{file|urlescape}{sessionvars%urlparameter}">
+        {node|short}
+      </a>
+    </td>
+  </tr>'
 filelogparent = '
   <tr>
     <td align="right">parent {rev}:&nbsp;</td>
@@ -215,6 +248,13 @@
       <a class="list" href="{url}diff/{node|short}/{file|urlescape}{sessionvars%urlparameter}">{node|short}</a>
     </td>
   </tr>'
+filecompchild = '
+  <tr>
+    <td>child {rev}</td>
+    <td style="font-family:monospace">
+      <a class="list" href="{url}comparison/{node|short}/{file|urlescape}{sessionvars%urlparameter}">{node|short}</a>
+    </td>
+  </tr>'
 filelogchild = '
   <tr>
     <td align="right">child {rev}:&nbsp;</td>
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/monoblue/fileannotate.tmpl
--- a/mercurial/templates/monoblue/fileannotate.tmpl	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/templates/monoblue/fileannotate.tmpl	Sun Jul 08 17:17:02 2012 +0200
@@ -35,6 +35,7 @@
         <li><a href="{url}log/{node|short}/{file|urlescape}{sessionvars%urlparameter}">revisions</a></li>
         <li class="current">annotate</li>
         <li><a href="{url}diff/{node|short}/{file|urlescape}{sessionvars%urlparameter}">diff</a></li>
+        <li><a href="{url}comparison/{node|short}/{file|urlescape}{sessionvars%urlparameter}">comparison</a></li>
         <li><a href="{url}raw-annotate/{node|short}/{file|urlescape}">raw</a></li>
     </ul>
 
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/monoblue/filecomparison.tmpl
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mercurial/templates/monoblue/filecomparison.tmpl	Sun Jul 08 17:17:02 2012 +0200
@@ -0,0 +1,64 @@
+{header}
+<title>{repo|escape}: comparison {file|escape}</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 id="container">
+    <div class="page-header">
+        <h1><a href="{url}summary{sessionvars%urlparameter}">{repo|escape}</a> / file comparison</h1>
+
+        <form action="{url}log">
+            {sessionvars%hiddenformentry}
+            <dl class="search">
+                <dt><label>Search: </label></dt>
+                <dd><input type="text" name="rev" /></dd>
+            </dl>
+        </form>
+
+        <ul class="page-nav">
+            <li><a href="{url}summary{sessionvars%urlparameter}">summary</a></li>
+            <li><a href="{url}shortlog{sessionvars%urlparameter}">shortlog</a></li>
+            <li><a href="{url}log{sessionvars%urlparameter}">changelog</a></li>
+            <li><a href="{url}graph/{node|short}{sessionvars%urlparameter}">graph</a></li>
+            <li><a href="{url}tags{sessionvars%urlparameter}">tags</a></li>
+            <li><a href="{url}bookmarks{sessionvars%urlparameter}">bookmarks</a></li>
+            <li><a href="{url}branches{sessionvars%urlparameter}">branches</a></li>
+            <li><a href="{url}file/{node|short}{path|urlescape}{sessionvars%urlparameter}">files</a></li>
+            <li><a href="{url}help{sessionvars%urlparameter}">help</a></li>
+        </ul>
+    </div>
+
+    <ul class="submenu">
+        <li><a href="{url}file/{node|short}/{file|urlescape}{sessionvars%urlparameter}">file</a></li>
+        <li><a href="{url}log/{node|short}/{file|urlescape}{sessionvars%urlparameter}">revisions</a></li>
+        <li><a href="{url}annotate/{node|short}/{file|urlescape}{sessionvars%urlparameter}">annotate</a></li>
+        <li><a href="{url}diff/{node|short}/{file|urlescape}{sessionvars%urlparameter}">diff</a></li>
+        <li class="current">comparison</li>
+        <li><a href="{url}raw-diff/{node|short}/{file|urlescape}">raw</a></li>
+    </ul>
+
+    <h2 class="no-link no-border">comparison: {file|escape}</h2>
+    <h3 class="changeset">{file|escape}</h3>
+
+    <dl class="overview">
+        {branch%filerevbranch}
+        <dt>changeset {rev}</dt>
+        <dd><a href="{url}rev/{node|short}{sessionvars%urlparameter}">{node|short}</a></dd>
+        {parent%filecompparent}
+        {child%filecompchild}
+    </dl>
+
+    <div class="legend">
+      <span class="legendinfo equal">equal</span>
+      <span class="legendinfo delete">deleted</span>
+      <span class="legendinfo insert">inserted</span>
+      <span class="legendinfo replace">replaced</span>
+    </div>
+
+    <div class="comparison">
+    {comparison}
+    </div>
+
+{footer}
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/monoblue/filediff.tmpl
--- a/mercurial/templates/monoblue/filediff.tmpl	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/templates/monoblue/filediff.tmpl	Sun Jul 08 17:17:02 2012 +0200
@@ -35,6 +35,7 @@
         <li><a href="{url}log/{node|short}/{file|urlescape}{sessionvars%urlparameter}">revisions</a></li>
         <li><a href="{url}annotate/{node|short}/{file|urlescape}{sessionvars%urlparameter}">annotate</a></li>
         <li class="current">diff</li>
+        <li><a href="{url}comparison/{node|short}/{file|urlescape}{sessionvars%urlparameter}">comparison</a></li>
         <li><a href="{url}raw-diff/{node|short}/{file|urlescape}">raw</a></li>
     </ul>
 
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/monoblue/filelog.tmpl
--- a/mercurial/templates/monoblue/filelog.tmpl	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/templates/monoblue/filelog.tmpl	Sun Jul 08 17:17:02 2012 +0200
@@ -35,6 +35,7 @@
         <li class="current">revisions</li>
         <li><a href="{url}annotate/{node|short}/{file|urlescape}{sessionvars%urlparameter}">annotate</a></li>
         <li><a href="{url}diff/{node|short}/{file|urlescape}{sessionvars%urlparameter}">diff</a></li>
+        <li><a href="{url}comparison/{node|short}/{file|urlescape}{sessionvars%urlparameter}">comparison</a></li>
         <li><a href="{url}rss-log/tip/{file|urlescape}">rss</a></li>
     </ul>
 
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/monoblue/filerevision.tmpl
--- a/mercurial/templates/monoblue/filerevision.tmpl	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/templates/monoblue/filerevision.tmpl	Sun Jul 08 17:17:02 2012 +0200
@@ -35,6 +35,7 @@
         <li><a href="{url}log/{node|short}/{file|urlescape}{sessionvars%urlparameter}">revisions</a></li>
         <li><a href="{url}annotate/{node|short}/{file|urlescape}{sessionvars%urlparameter}">annotate</a></li>
         <li><a href="{url}diff/{node|short}/{file|urlescape}{sessionvars%urlparameter}">diff</a></li>
+        <li><a href="{url}comparison/{node|short}/{file|urlescape}{sessionvars%urlparameter}">comparison</a></li>
         <li><a href="{url}raw-file/{node|short}/{file|urlescape}">raw</a></li>
     </ul>
 
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/monoblue/map
--- a/mercurial/templates/monoblue/map	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/templates/monoblue/map	Sun Jul 08 17:17:02 2012 +0200
@@ -26,6 +26,7 @@
       <a href="{url}file/{node|short}/{file|urlescape}{sessionvars%urlparameter}">file</a> |
       <a href="{url}annotate/{node|short}/{file|urlescape}{sessionvars%urlparameter}">annotate</a> |
       <a href="{url}diff/{node|short}/{file|urlescape}{sessionvars%urlparameter}">diff</a> |
+      <a href="{url}comparison/{node|short}/{file|urlescape}{sessionvars%urlparameter}">comparison</a> |
       <a href="{url}log/{node|short}/{file|urlescape}{sessionvars%urlparameter}">revisions</a>
     </td>
   </tr>'
@@ -37,6 +38,7 @@
       file |
       annotate |
       <a href="{url}diff/{node|short}/{file|urlescape}{sessionvars%urlparameter}">diff</a> |
+      <a href="{url}comparison/{node|short}/{file|urlescape}{sessionvars%urlparameter}">comparison</a> |
       <a href="{url}log/{node|short}/{file|urlescape}{sessionvars%urlparameter}">revisions</a>
     </td>
   </tr>'
@@ -74,6 +76,7 @@
 filerevision = filerevision.tmpl
 fileannotate = fileannotate.tmpl
 filediff = filediff.tmpl
+filecomparison = filecomparison.tmpl
 filelog = filelog.tmpl
 fileline = '
   <div style="font-family:monospace" class="parity{parity}">
@@ -94,6 +97,27 @@
 difflineminus = '<span style="color:#cc0000;"><a class="linenr" href="#{lineid}" id="{lineid}">{linenumber}</a> {line|escape}</span>'
 difflineat = '<span style="color:#990099;"><a class="linenr" href="#{lineid}" id="{lineid}">{linenumber}</a> {line|escape}</span>'
 diffline = '<span><a class="linenr" href="#{lineid}" id="{lineid}">{linenumber}</a> {line|escape}</span>'
+
+comparison = '
+  <table class="bigtable">
+    <thead class="header">
+      <tr>
+        <th>{leftrev}:{leftnode|short}</th>
+        <th>{rightrev}:{rightnode|short}</th>
+      </tr>
+    </thead>
+    {blocks}
+  </table>'
+comparisonblock ='
+  <tbody class="block">
+  {lines}
+  </tbody>'
+comparisonline = '
+  <tr>
+    <td class="source {type}"><a class="linenr" href="#{lineid}" id="{lineid}">{leftlinenumber}</a> {leftline|escape}</td>
+    <td class="source {type}"><a class="linenr" href="#{lineid}" id="{lineid}">{rightlinenumber}</a> {rightline|escape}</td>
+  </tr>'
+
 changelogparent = '
   <tr>
     <th class="parent">parent {rev}:</th>
@@ -176,6 +200,9 @@
 filediffparent = '
   <dt>parent {rev}</dt>
   <dd><a href="{url}diff/{node|short}/{file|urlescape}{sessionvars%urlparameter}">{node|short}</a></dd>'
+filecompparent = '
+  <dt>parent {rev}</dt>
+  <dd><a href="{url}comparison/{node|short}/{file|urlescape}{sessionvars%urlparameter}">{node|short}</a></dd>'
 filelogparent = '
   <tr>
     <td align="right">parent {rev}:&nbsp;</td>
@@ -184,6 +211,9 @@
 filediffchild = '
   <dt>child {rev}</dt>
   <dd><a href="{url}diff/{node|short}/{file|urlescape}{sessionvars%urlparameter}">{node|short}</a></dd>'
+filecompchild = '
+  <dt>child {rev}</dt>
+  <dd><a href="{url}comparison/{node|short}/{file|urlescape}{sessionvars%urlparameter}">{node|short}</a></dd>'
 filelogchild = '
   <tr>
     <td align="right">child {rev}:&nbsp;</td>
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/paper/fileannotate.tmpl
--- a/mercurial/templates/paper/fileannotate.tmpl	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/templates/paper/fileannotate.tmpl	Sun Jul 08 17:17:02 2012 +0200
@@ -25,6 +25,7 @@
 <li><a href="{url}file/{node|short}/{file|urlescape}{sessionvars%urlparameter}">file</a></li>
 <li><a href="{url}file/tip/{file|urlescape}{sessionvars%urlparameter}">latest</a></li>
 <li><a href="{url}diff/{node|short}/{file|urlescape}{sessionvars%urlparameter}">diff</a></li>
+<li><a href="{url}comparison/{node|short}/{file|urlescape}{sessionvars%urlparameter}">comparison</a></li>
 <li class="active">annotate</li>
 <li><a href="{url}log/{node|short}/{file|urlescape}{sessionvars%urlparameter}">file log</a></li>
 <li><a href="{url}raw-annotate/{node|short}/{file|urlescape}">raw</a></li>
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/paper/filecomparison.tmpl
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mercurial/templates/paper/filecomparison.tmpl	Sun Jul 08 17:17:02 2012 +0200
@@ -0,0 +1,85 @@
+{header}
+<title>{repo|escape}: {file|escape} comparison</title>
+</head>
+<body>
+
+<div class="container">
+<div class="menu">
+<div class="logo">
+<a href="{logourl}">
+<img src="{staticurl}{logoimg}" alt="mercurial" /></a>
+</div>
+<ul>
+<li><a href="{url}shortlog/{node|short}{sessionvars%urlparameter}">log</a></li>
+<li><a href="{url}graph/{node|short}{sessionvars%urlparameter}">graph</a></li>
+<li><a href="{url}tags{sessionvars%urlparameter}">tags</a></li>
+<li><a href="{url}bookmarks{sessionvars%urlparameter}">bookmarks</a></li>
+<li><a href="{url}branches{sessionvars%urlparameter}">branches</a></li>
+</ul>
+<ul>
+<li><a href="{url}rev/{node|short}{sessionvars%urlparameter}">changeset</a></li>
+<li><a href="{url}file/{node|short}{path|urlescape}{sessionvars%urlparameter}">browse</a></li>
+</ul>
+<ul>
+<li><a href="{url}file/{node|short}/{file|urlescape}{sessionvars%urlparameter}">file</a></li>
+<li><a href="{url}file/tip/{file|urlescape}{sessionvars%urlparameter}">latest</a></li>
+<li><a href="{url}diff/{node|short}/{file|urlescape}{sessionvars%urlparameter}">diff</a></li>
+<li class="active">comparison</li>
+<li><a href="{url}annotate/{node|short}/{file|urlescape}{sessionvars%urlparameter}">annotate</a></li>
+<li><a href="{url}log/{node|short}/{file|urlescape}{sessionvars%urlparameter}">file log</a></li>
+<li><a href="{url}raw-file/{node|short}/{file|urlescape}">raw</a></li>
+</ul>
+<ul>
+<li><a href="{url}help{sessionvars%urlparameter}">help</a></li>
+</ul>
+</div>
+
+<div class="main">
+<h2><a href="{url}{sessionvars%urlparameter}">{repo|escape}</a></h2>
+<h3>comparison {file|escape} @ {rev}:{node|short}</h3>
+
+<form class="search" action="{url}log">
+<p>{sessionvars%hiddenformentry}</p>
+<p><input name="rev" id="search1" type="text" size="30" /></p>
+<div id="hint">find changesets by author, revision,
+files, or words in the commit message</div>
+</form>
+
+<div class="description">{desc|strip|escape|nonempty}</div>
+
+<table id="changesetEntry">
+<tr>
+ <th>author</th>
+ <td>{author|obfuscate}</td>
+</tr>
+<tr>
+ <th>date</th>
+ <td class="date age">{date|rfc822date}</td>
+</tr>
+<tr>
+ <th>parents</th>
+ <td>{parent%filerevparent}</td>
+</tr>
+<tr>
+ <th>children</th>
+ <td>{child%filerevchild}</td>
+</tr>
+{changesettag}
+</table>
+
+<div class="overflow">
+<div class="sourcefirst">   comparison</div>
+<div class="legend">
+  <span class="legendinfo equal">equal</span>
+  <span class="legendinfo delete">deleted</span>
+  <span class="legendinfo insert">inserted</span>
+  <span class="legendinfo replace">replaced</span>
+</div>
+
+{comparison}
+
+</div>
+</div>
+</div>
+
+{footer}
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/paper/filediff.tmpl
--- a/mercurial/templates/paper/filediff.tmpl	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/templates/paper/filediff.tmpl	Sun Jul 08 17:17:02 2012 +0200
@@ -24,6 +24,7 @@
 <li><a href="{url}file/{node|short}/{file|urlescape}{sessionvars%urlparameter}">file</a></li>
 <li><a href="{url}file/tip/{file|urlescape}{sessionvars%urlparameter}">latest</a></li>
 <li class="active">diff</li>
+<li><a href="{url}comparison/{node|short}/{file|urlescape}{sessionvars%urlparameter}">comparison</a></li>
 <li><a href="{url}annotate/{node|short}/{file|urlescape}{sessionvars%urlparameter}">annotate</a></li>
 <li><a href="{url}log/{node|short}/{file|urlescape}{sessionvars%urlparameter}">file log</a></li>
 <li><a href="{url}raw-file/{node|short}/{file|urlescape}">raw</a></li>
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/paper/filelog.tmpl
--- a/mercurial/templates/paper/filelog.tmpl	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/templates/paper/filelog.tmpl	Sun Jul 08 17:17:02 2012 +0200
@@ -27,6 +27,7 @@
 <ul>
 <li><a href="{url}file/{node|short}/{file|urlescape}{sessionvars%urlparameter}">file</a></li>
 <li><a href="{url}diff/{node|short}/{file|urlescape}{sessionvars%urlparameter}">diff</a></li>
+<li><a href="{url}comparison/{node|short}/{file|urlescape}{sessionvars%urlparameter}">comparison</a></li>
 <li><a href="{url}annotate/{node|short}/{file|urlescape}{sessionvars%urlparameter}">annotate</a></li>
 <li class="active">file log</li>
 <li><a href="{url}raw-file/{node|short}/{file|urlescape}">raw</a></li>
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/paper/filerevision.tmpl
--- a/mercurial/templates/paper/filerevision.tmpl	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/templates/paper/filerevision.tmpl	Sun Jul 08 17:17:02 2012 +0200
@@ -23,6 +23,7 @@
 <li class="active">file</li>
 <li><a href="{url}file/tip/{file|urlescape}{sessionvars%urlparameter}">latest</a></li>
 <li><a href="{url}diff/{node|short}/{file|urlescape}{sessionvars%urlparameter}">diff</a></li>
+<li><a href="{url}comparison/{node|short}/{file|urlescape}{sessionvars%urlparameter}">comparison</a></li>
 <li><a href="{url}annotate/{node|short}/{file|urlescape}{sessionvars%urlparameter}">annotate</a></li>
 <li><a href="{url}log/{node|short}/{file|urlescape}{sessionvars%urlparameter}">file log</a></li>
 <li><a href="{url}raw-file/{node|short}/{file|urlescape}">raw</a></li>
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/paper/map
--- a/mercurial/templates/paper/map	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/templates/paper/map	Sun Jul 08 17:17:02 2012 +0200
@@ -62,6 +62,7 @@
 filerevision = filerevision.tmpl
 fileannotate = fileannotate.tmpl
 filediff = filediff.tmpl
+filecomparison = filecomparison.tmpl
 filelog = filelog.tmpl
 fileline = '
   <div class="parity{parity} source"><a href="#{lineid}" id="{lineid}">{linenumber}</a> {line|escape}</div>'
@@ -82,6 +83,26 @@
 difflineat = '<a href="#{lineid}" id="{lineid}">{linenumber}</a> <span class="atline">{line|escape}</span>'
 diffline = '<a href="#{lineid}" id="{lineid}">{linenumber}</a> {line|escape}'
 
+comparison = '
+  <table class="bigtable">
+    <thead class="header">
+      <tr>
+        <th>{leftrev}:{leftnode|short}</th>
+        <th>{rightrev}:{rightnode|short}</th>
+      </tr>
+    </thead>
+    {blocks}
+  </table>'
+comparisonblock ='
+  <tbody class="block">
+  {lines}
+  </tbody>'
+comparisonline = '
+  <tr>
+    <td class="source {type}"><a href="#{lineid}" id="{lineid}">{leftlinenumber}</a> {leftline|escape}</td>
+    <td class="source {type}"><a href="#{lineid}" id="{lineid}">{rightlinenumber}</a> {rightline|escape}</td>
+  </tr>'
+
 changelogparent = '
   <tr>
     <th class="parent">parent {rev}:</th>
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/static/style-coal.css
--- a/mercurial/templates/static/style-coal.css	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/templates/static/style-coal.css	Sun Jul 08 17:17:02 2012 +0200
@@ -286,3 +286,40 @@
 	position: relative;
 	top: -3px;
 }
+
+/* Comparison */
+.legend {
+    padding: 1.5% 0 1.5% 0;
+}
+
+.legendinfo {
+    border: 1px solid #999;
+    font-size: 80%;
+    text-align: center;
+    padding: 0.5%;
+}
+
+.equal {
+    background-color: #ffffff;
+}
+
+.delete {
+    background-color: black;
+    color: white;
+}
+
+.insert {
+    background-color: #d0d0d0;
+}
+
+.replace {
+    background-color: #f9f9f9;
+}
+
+.header {
+    text-align: center;
+}
+
+.block {
+    border-top: 1px solid #999;
+}
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/static/style-gitweb.css
--- a/mercurial/templates/static/style-gitweb.css	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/templates/static/style-gitweb.css	Sun Jul 08 17:17:02 2012 +0200
@@ -126,3 +126,43 @@
 	top: -3px;
 	font-style: italic;
 }
+
+/* Comparison */
+.legend {
+    padding: 1.5% 0 1.5% 0;
+}
+
+.legendinfo {
+    border: 1px solid #d9d8d1;
+    font-size: 80%;
+    text-align: center;
+    padding: 0.5%;
+}
+
+.equal {
+    background-color: #ffffff;
+}
+
+.delete {
+    background-color: #ffc5ce;
+}
+
+.insert {
+    background-color: #c5ffc4;
+}
+
+.replace {
+    background-color: #ffff99;
+}
+
+.comparison {
+    overflow-x: auto;
+}
+
+.header th {
+    text-align: center;
+}
+
+.block {
+    border-top: 1px solid #d9d8d1;
+}
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/static/style-monoblue.css
--- a/mercurial/templates/static/style-monoblue.css	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/templates/static/style-monoblue.css	Sun Jul 08 17:17:02 2012 +0200
@@ -477,3 +477,49 @@
 	position: relative;
 }
 /** end of canvas **/
+
+/** comparison **/
+.legend {
+    margin-left: 20px;
+    padding: 1.5% 0 1.5% 0;
+}
+
+.legendinfo {
+    border: 1px solid #999;
+    font-size: 80%;
+    text-align: center;
+    padding: 0.5%;
+}
+
+.equal {
+    background-color: #ffffff;
+}
+
+.delete {
+    background-color: #ffc5ce;
+}
+
+.insert {
+    background-color: #c5ffc4;
+}
+
+.replace {
+    background-color: #ffff99;
+}
+
+.comparison {
+    overflow-x: auto;
+}
+
+.comparison table td {
+    padding: 0px 5px;
+}
+
+.header th {
+    font-weight: bold;
+}
+
+.block {
+    border-top: 1px solid #999;
+}
+/** end of comparison **/
diff -r afd75476939e -r 1ae119269ddc mercurial/templates/static/style-paper.css
--- a/mercurial/templates/static/style-paper.css	Fri Jul 06 13:56:40 2012 -0700
+++ b/mercurial/templates/static/style-paper.css	Sun Jul 08 17:17:02 2012 +0200
@@ -275,3 +275,39 @@
 	position: relative;
 	top: -3px;
 }
+
+/* Comparison */
+.legend {
+    padding: 1.5% 0 1.5% 0;
+}
+
+.legendinfo {
+    border: 1px solid #999;
+    font-size: 80%;
+    text-align: center;
+    padding: 0.5%;
+}
+
+.equal {
+    background-color: #ffffff;
+}
+
+.delete {
+    background-color: #ffc5ce;
+}
+
+.insert {
+    background-color: #c5ffc4;
+}
+
+.replace {
+    background-color: #ffff99;
+}
+
+.header {
+    text-align: center;
+}
+
+.block {
+    border-top: 1px solid #999;
+}
diff -r afd75476939e -r 1ae119269ddc tests/test-hgweb-commands.t
--- a/tests/test-hgweb-commands.t	Fri Jul 06 13:56:40 2012 -0700
+++ b/tests/test-hgweb-commands.t	Sun Jul 08 17:17:02 2012 +0200
@@ -605,6 +605,7 @@
   <li class="active">file</li>
   <li><a href="/file/tip/foo">latest</a></li>
   <li><a href="/diff/a4f92ed23982/foo">diff</a></li>
+  <li><a href="/comparison/a4f92ed23982/foo">comparison</a></li>
   <li><a href="/annotate/a4f92ed23982/foo">annotate</a></li>
   <li><a href="/log/a4f92ed23982/foo">file log</a></li>
   <li><a href="/raw-file/a4f92ed23982/foo">raw</a></li>
diff -r afd75476939e -r 1ae119269ddc tests/test-hgweb-diffs.t
--- a/tests/test-hgweb-diffs.t	Fri Jul 06 13:56:40 2012 -0700
+++ b/tests/test-hgweb-diffs.t	Sun Jul 08 17:17:02 2012 +0200
@@ -227,6 +227,7 @@
   <li><a href="/file/559edbd9ed20/b">file</a></li>
   <li><a href="/file/tip/b">latest</a></li>
   <li class="active">diff</li>
+  <li><a href="/comparison/559edbd9ed20/b">comparison</a></li>
   <li><a href="/annotate/559edbd9ed20/b">annotate</a></li>
   <li><a href="/log/559edbd9ed20/b">file log</a></li>
   <li><a href="/raw-file/559edbd9ed20/b">raw</a></li>
@@ -491,6 +492,7 @@
   <li><a href="/file/559edbd9ed20/a">file</a></li>
   <li><a href="/file/tip/a">latest</a></li>
   <li class="active">diff</li>
+  <li><a href="/comparison/559edbd9ed20/a">comparison</a></li>
   <li><a href="/annotate/559edbd9ed20/a">annotate</a></li>
   <li><a href="/log/559edbd9ed20/a">file log</a></li>
   <li><a href="/raw-file/559edbd9ed20/a">raw</a></li>
@@ -549,6 +551,378 @@
   </body>
   </html>
   
+
+comparison new file
+
+  $ "$TESTDIR/get-with-headers.py" localhost:$HGPORT 'comparison/0/a'
+  200 Script output follows
+  
+  <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
+  <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US">
+  <head>
+  <link rel="icon" href="/static/hgicon.png" type="image/png" />
+  <meta name="robots" content="index, nofollow" />
+  <link rel="stylesheet" href="/static/style-paper.css" type="text/css" />
+  <script type="text/javascript" src="/static/mercurial.js"></script>
+  
+  <title>test: a comparison</title>
+  </head>
+  <body>
+  
+  <div class="container">
+  <div class="menu">
+  <div class="logo">
+  <a href="http://mercurial.selenic.com/">
+  <img src="/static/hglogo.png" alt="mercurial" /></a>
+  </div>
+  <ul>
+  <li><a href="/shortlog/0cd96de13884">log</a></li>
+  <li><a href="/graph/0cd96de13884">graph</a></li>
+  <li><a href="/tags">tags</a></li>
+  <li><a href="/bookmarks">bookmarks</a></li>
+  <li><a href="/branches">branches</a></li>
+  </ul>
+  <ul>
+  <li><a href="/rev/0cd96de13884">changeset</a></li>
+  <li><a href="/file/0cd96de13884">browse</a></li>
+  </ul>
+  <ul>
+  <li><a href="/file/0cd96de13884/a">file</a></li>
+  <li><a href="/file/tip/a">latest</a></li>
+  <li><a href="/diff/0cd96de13884/a">diff</a></li>
+  <li class="active">comparison</li>
+  <li><a href="/annotate/0cd96de13884/a">annotate</a></li>
+  <li><a href="/log/0cd96de13884/a">file log</a></li>
+  <li><a href="/raw-file/0cd96de13884/a">raw</a></li>
+  </ul>
+  <ul>
+  <li><a href="/help">help</a></li>
+  </ul>
+  </div>
+  
+  <div class="main">
+  <h2><a href="/">test</a></h2>
+  <h3>comparison a @ 0:0cd96de13884</h3>
+  
+  <form class="search" action="/log">
+  <p></p>
+  <p><input name="rev" id="search1" type="text" size="30" /></p>
+  <div id="hint">find changesets by author, revision,
+  files, or words in the commit message</div>
+  </form>
+  
+  <div class="description">a</div>
+  
+  <table id="changesetEntry">
+  <tr>
+   <th>author</th>
+   <td>&#116;&#101;&#115;&#116;</td>
+  </tr>
+  <tr>
+   <th>date</th>
+   <td class="date age">Thu, 01 Jan 1970 00:00:00 +0000</td>
+  </tr>
+  <tr>
+   <th>parents</th>
+   <td></td>
+  </tr>
+  <tr>
+   <th>children</th>
+   <td><a href="/file/559edbd9ed20/a">559edbd9ed20</a> </td>
+  </tr>
+  
+  </table>
+  
+  <div class="overflow">
+  <div class="sourcefirst">   comparison</div>
+  <div class="legend">
+    <span class="legendinfo equal">equal</span>
+    <span class="legendinfo delete">deleted</span>
+    <span class="legendinfo insert">inserted</span>
+    <span class="legendinfo replace">replaced</span>
+  </div>
+  
+  
+  <table class="bigtable">
+  <thead class="header">
+  <tr>
+  <th>-1:000000000000</th>
+  <th>0:b789fdd96dc2</th>
+  </tr>
+  </thead>
+  
+  <tbody class="block">
+  
+  <tr>
+  <td class="source insert"><a href="#r1" id="r1">      </a> </td>
+  <td class="source insert"><a href="#r1" id="r1">     1</a> a</td>
+  </tr>
+  </tbody>
+  </table>
+  
+  </div>
+  </div>
+  </div>
+  
+  <script type="text/javascript">process_dates()</script>
+  
+  
+  </body>
+  </html>
+  
+
+comparison existing file
+
+  $ hg up
+  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
+  $ echo a >> a
+  $ hg ci -mc
+  $ "$TESTDIR/get-with-headers.py" localhost:$HGPORT 'comparison/tip/a'
+  200 Script output follows
+  
+  <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
+  <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US">
+  <head>
+  <link rel="icon" href="/static/hgicon.png" type="image/png" />
+  <meta name="robots" content="index, nofollow" />
+  <link rel="stylesheet" href="/static/style-paper.css" type="text/css" />
+  <script type="text/javascript" src="/static/mercurial.js"></script>
+  
+  <title>test: a comparison</title>
+  </head>
+  <body>
+  
+  <div class="container">
+  <div class="menu">
+  <div class="logo">
+  <a href="http://mercurial.selenic.com/">
+  <img src="/static/hglogo.png" alt="mercurial" /></a>
+  </div>
+  <ul>
+  <li><a href="/shortlog/d73db4d812ff">log</a></li>
+  <li><a href="/graph/d73db4d812ff">graph</a></li>
+  <li><a href="/tags">tags</a></li>
+  <li><a href="/bookmarks">bookmarks</a></li>
+  <li><a href="/branches">branches</a></li>
+  </ul>
+  <ul>
+  <li><a href="/rev/d73db4d812ff">changeset</a></li>
+  <li><a href="/file/d73db4d812ff">browse</a></li>
+  </ul>
+  <ul>
+  <li><a href="/file/d73db4d812ff/a">file</a></li>
+  <li><a href="/file/tip/a">latest</a></li>
+  <li><a href="/diff/d73db4d812ff/a">diff</a></li>
+  <li class="active">comparison</li>
+  <li><a href="/annotate/d73db4d812ff/a">annotate</a></li>
+  <li><a href="/log/d73db4d812ff/a">file log</a></li>
+  <li><a href="/raw-file/d73db4d812ff/a">raw</a></li>
+  </ul>
+  <ul>
+  <li><a href="/help">help</a></li>
+  </ul>
+  </div>
+  
+  <div class="main">
+  <h2><a href="/">test</a></h2>
+  <h3>comparison a @ 2:d73db4d812ff</h3>
+  
+  <form class="search" action="/log">
+  <p></p>
+  <p><input name="rev" id="search1" type="text" size="30" /></p>
+  <div id="hint">find changesets by author, revision,
+  files, or words in the commit message</div>
+  </form>
+  
+  <div class="description">c</div>
+  
+  <table id="changesetEntry">
+  <tr>
+   <th>author</th>
+   <td>&#116;&#101;&#115;&#116;</td>
+  </tr>
+  <tr>
+   <th>date</th>
+   <td class="date age">Thu, 01 Jan 1970 00:00:00 +0000</td>
+  </tr>
+  <tr>
+   <th>parents</th>
+   <td><a href="/file/559edbd9ed20/a">559edbd9ed20</a> </td>
+  </tr>
+  <tr>
+   <th>children</th>
+   <td></td>
+  </tr>
+  
+  </table>
+  
+  <div class="overflow">
+  <div class="sourcefirst">   comparison</div>
+  <div class="legend">
+    <span class="legendinfo equal">equal</span>
+    <span class="legendinfo delete">deleted</span>
+    <span class="legendinfo insert">inserted</span>
+    <span class="legendinfo replace">replaced</span>
+  </div>
+  
+  
+  <table class="bigtable">
+  <thead class="header">
+  <tr>
+  <th>0:b789fdd96dc2</th>
+  <th>1:a80d06849b33</th>
+  </tr>
+  </thead>
+  
+  <tbody class="block">
+  
+  <tr>
+  <td class="source equal"><a href="#l1r1" id="l1r1">     1</a> a</td>
+  <td class="source equal"><a href="#l1r1" id="l1r1">     1</a> a</td>
+  </tr>
+  <tr>
+  <td class="source insert"><a href="#r2" id="r2">      </a> </td>
+  <td class="source insert"><a href="#r2" id="r2">     2</a> a</td>
+  </tr>
+  </tbody>
+  </table>
+  
+  </div>
+  </div>
+  </div>
+  
+  <script type="text/javascript">process_dates()</script>
+  
+  
+  </body>
+  </html>
+  
+
+comparison removed file
+
+  $ hg rm a
+  $ hg ci -md
+  $ "$TESTDIR/get-with-headers.py" localhost:$HGPORT 'comparison/tip/a'
+  200 Script output follows
+  
+  <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
+  <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US">
+  <head>
+  <link rel="icon" href="/static/hgicon.png" type="image/png" />
+  <meta name="robots" content="index, nofollow" />
+  <link rel="stylesheet" href="/static/style-paper.css" type="text/css" />
+  <script type="text/javascript" src="/static/mercurial.js"></script>
+  
+  <title>test: a comparison</title>
+  </head>
+  <body>
+  
+  <div class="container">
+  <div class="menu">
+  <div class="logo">
+  <a href="http://mercurial.selenic.com/">
+  <img src="/static/hglogo.png" alt="mercurial" /></a>
+  </div>
+  <ul>
+  <li><a href="/shortlog/20e80271eb7a">log</a></li>
+  <li><a href="/graph/20e80271eb7a">graph</a></li>
+  <li><a href="/tags">tags</a></li>
+  <li><a href="/bookmarks">bookmarks</a></li>
+  <li><a href="/branches">branches</a></li>
+  </ul>
+  <ul>
+  <li><a href="/rev/20e80271eb7a">changeset</a></li>
+  <li><a href="/file/20e80271eb7a">browse</a></li>
+  </ul>
+  <ul>
+  <li><a href="/file/20e80271eb7a/a">file</a></li>
+  <li><a href="/file/tip/a">latest</a></li>
+  <li><a href="/diff/20e80271eb7a/a">diff</a></li>
+  <li class="active">comparison</li>
+  <li><a href="/annotate/20e80271eb7a/a">annotate</a></li>
+  <li><a href="/log/20e80271eb7a/a">file log</a></li>
+  <li><a href="/raw-file/20e80271eb7a/a">raw</a></li>
+  </ul>
+  <ul>
+  <li><a href="/help">help</a></li>
+  </ul>
+  </div>
+  
+  <div class="main">
+  <h2><a href="/">test</a></h2>
+  <h3>comparison a @ 3:20e80271eb7a</h3>
+  
+  <form class="search" action="/log">
+  <p></p>
+  <p><input name="rev" id="search1" type="text" size="30" /></p>
+  <div id="hint">find changesets by author, revision,
+  files, or words in the commit message</div>
+  </form>
+  
+  <div class="description">d</div>
+  
+  <table id="changesetEntry">
+  <tr>
+   <th>author</th>
+   <td>&#116;&#101;&#115;&#116;</td>
+  </tr>
+  <tr>
+   <th>date</th>
+   <td class="date age">Thu, 01 Jan 1970 00:00:00 +0000</td>
+  </tr>
+  <tr>
+   <th>parents</th>
+   <td><a href="/file/d73db4d812ff/a">d73db4d812ff</a> </td>
+  </tr>
+  <tr>
+   <th>children</th>
+   <td></td>
+  </tr>
+  
+  </table>
+  
+  <div class="overflow">
+  <div class="sourcefirst">   comparison</div>
+  <div class="legend">
+    <span class="legendinfo equal">equal</span>
+    <span class="legendinfo delete">deleted</span>
+    <span class="legendinfo insert">inserted</span>
+    <span class="legendinfo replace">replaced</span>
+  </div>
+  
+  
+  <table class="bigtable">
+  <thead class="header">
+  <tr>
+  <th>1:a80d06849b33</th>
+  <th>-1:000000000000</th>
+  </tr>
+  </thead>
+  
+  <tbody class="block">
+  
+  <tr>
+  <td class="source delete"><a href="#l1" id="l1">     1</a> a</td>
+  <td class="source delete"><a href="#l1" id="l1">      </a> </td>
+  </tr>
+  <tr>
+  <td class="source delete"><a href="#l2" id="l2">     2</a> a</td>
+  <td class="source delete"><a href="#l2" id="l2">      </a> </td>
+  </tr>
+  </tbody>
+  </table>
+  
+  </div>
+  </div>
+  </div>
+  
+  <script type="text/javascript">process_dates()</script>
+  
+  
+  </body>
+  </html>
+  
+
   $ cd ..
 
 test import rev as raw-rev
diff -r afd75476939e -r 1ae119269ddc tests/test-hgweb-filelog.t
--- a/tests/test-hgweb-filelog.t	Fri Jul 06 13:56:40 2012 -0700
+++ b/tests/test-hgweb-filelog.t	Sun Jul 08 17:17:02 2012 +0200
@@ -148,6 +148,7 @@
   <ul>
   <li><a href="/file/01de2d66a28d/a">file</a></li>
   <li><a href="/diff/01de2d66a28d/a">diff</a></li>
+  <li><a href="/comparison/01de2d66a28d/a">comparison</a></li>
   <li><a href="/annotate/01de2d66a28d/a">annotate</a></li>
   <li class="active">file log</li>
   <li><a href="/raw-file/01de2d66a28d/a">raw</a></li>
@@ -249,6 +250,7 @@
   <ul>
   <li><a href="/file/01de2d66a28d/a">file</a></li>
   <li><a href="/diff/01de2d66a28d/a">diff</a></li>
+  <li><a href="/comparison/01de2d66a28d/a">comparison</a></li>
   <li><a href="/annotate/01de2d66a28d/a">annotate</a></li>
   <li class="active">file log</li>
   <li><a href="/raw-file/01de2d66a28d/a">raw</a></li>
@@ -350,6 +352,7 @@
   <ul>
   <li><a href="/file/5ed941583260/a">file</a></li>
   <li><a href="/diff/5ed941583260/a">diff</a></li>
+  <li><a href="/comparison/5ed941583260/a">comparison</a></li>
   <li><a href="/annotate/5ed941583260/a">annotate</a></li>
   <li class="active">file log</li>
   <li><a href="/raw-file/5ed941583260/a">raw</a></li>
@@ -446,6 +449,7 @@
   <ul>
   <li><a href="/file/5ed941583260/a">file</a></li>
   <li><a href="/diff/5ed941583260/a">diff</a></li>
+  <li><a href="/comparison/5ed941583260/a">comparison</a></li>
   <li><a href="/annotate/5ed941583260/a">annotate</a></li>
   <li class="active">file log</li>
   <li><a href="/raw-file/5ed941583260/a">raw</a></li>
diff -r afd75476939e -r 1ae119269ddc tests/test-hgweb-removed.t
--- a/tests/test-hgweb-removed.t	Fri Jul 06 13:56:40 2012 -0700
+++ b/tests/test-hgweb-removed.t	Sun Jul 08 17:17:02 2012 +0200
@@ -171,6 +171,7 @@
   <li><a href="/file/c78f6c5cbea9/a">file</a></li>
   <li><a href="/file/tip/a">latest</a></li>
   <li class="active">diff</li>
+  <li><a href="/comparison/c78f6c5cbea9/a">comparison</a></li>
   <li><a href="/annotate/c78f6c5cbea9/a">annotate</a></li>
   <li><a href="/log/c78f6c5cbea9/a">file log</a></li>
   <li><a href="/raw-file/c78f6c5cbea9/a">raw</a></li>
diff -r afd75476939e -r 1ae119269ddc tests/test-hgweb.t
--- a/tests/test-hgweb.t	Fri Jul 06 13:56:40 2012 -0700
+++ b/tests/test-hgweb.t	Sun Jul 08 17:17:02 2012 +0200
@@ -437,6 +437,46 @@
   	top: -3px;
   	font-style: italic;
   }
+  
+  /* Comparison */
+  .legend {
+      padding: 1.5% 0 1.5% 0;
+  }
+  
+  .legendinfo {
+      border: 1px solid #d9d8d1;
+      font-size: 80%;
+      text-align: center;
+      padding: 0.5%;
+  }
+  
+  .equal {
+      background-color: #ffffff;
+  }
+  
+  .delete {
+      background-color: #ffc5ce;
+  }
+  
+  .insert {
+      background-color: #c5ffc4;
+  }
+  
+  .replace {
+      background-color: #ffff99;
+  }
+  
+  .comparison {
+      overflow-x: auto;
+  }
+  
+  .header th {
+      text-align: center;
+  }
+  
+  .block {
+      border-top: 1px solid #d9d8d1;
+  }
   304 Not Modified
   
 
diff -r afd75476939e -r 1ae119269ddc tests/test-highlight.t
--- a/tests/test-highlight.t	Fri Jul 06 13:56:40 2012 -0700
+++ b/tests/test-highlight.t	Sun Jul 08 17:17:02 2012 +0200
@@ -92,6 +92,7 @@
   <li class="active">file</li>
   <li><a href="/file/tip/primes.py">latest</a></li>
   <li><a href="/diff/853dcd4de2a6/primes.py">diff</a></li>
+  <li><a href="/comparison/853dcd4de2a6/primes.py">comparison</a></li>
   <li><a href="/annotate/853dcd4de2a6/primes.py">annotate</a></li>
   <li><a href="/log/853dcd4de2a6/primes.py">file log</a></li>
   <li><a href="/raw-file/853dcd4de2a6/primes.py">raw</a></li>
@@ -222,6 +223,7 @@
   <li><a href="/file/853dcd4de2a6/primes.py">file</a></li>
   <li><a href="/file/tip/primes.py">latest</a></li>
   <li><a href="/diff/853dcd4de2a6/primes.py">diff</a></li>
+  <li><a href="/comparison/853dcd4de2a6/primes.py">comparison</a></li>
   <li class="active">annotate</li>
   <li><a href="/log/853dcd4de2a6/primes.py">file log</a></li>
   <li><a href="/raw-annotate/853dcd4de2a6/primes.py">raw</a></li>