# HG changeset patch
# User Denis Laxalde <denis.laxalde@logilab.fr>
# Date 1493022735 -7200
# Node ID a298f5c61b34237579205d9ece9855e998446ab6
# Parent  a457da5296a5ad25c2b5cc22509c3340fd4e48f8
hgweb: do not show "descending" link in followlines UI for filelog heads

When on a filelog head, we are certain that there will be no descendant so the
target of the "descending" link will lead to an empty log result. Do not
display the link in this case.

diff -r a457da5296a5 -r a298f5c61b34 mercurial/hgweb/webcommands.py
--- a/mercurial/hgweb/webcommands.py	Mon Apr 24 18:33:23 2017 +0200
+++ b/mercurial/hgweb/webcommands.py	Mon Apr 24 10:32:15 2017 +0200
@@ -131,6 +131,7 @@
     f = fctx.path()
     text = fctx.data()
     parity = paritygen(web.stripecount)
+    ishead = fctx.filerev() in fctx.filelog().headrevs()
 
     if util.binary(text):
         mt = mimetypes.guess_type(f)[0] or 'application/octet-stream'
@@ -150,6 +151,7 @@
                 symrev=webutil.symrevorshortnode(req, fctx),
                 rename=webutil.renamelink(fctx),
                 permissions=fctx.manifest().flags(f),
+                ishead=int(ishead),
                 **webutil.commonentry(web.repo, fctx))
 
 @webcommand('file')
diff -r a457da5296a5 -r a298f5c61b34 mercurial/templates/gitweb/filerevision.tmpl
--- a/mercurial/templates/gitweb/filerevision.tmpl	Mon Apr 24 18:33:23 2017 +0200
+++ b/mercurial/templates/gitweb/filerevision.tmpl	Mon Apr 24 10:32:15 2017 +0200
@@ -64,7 +64,7 @@
 </div>
 
 <div class="page_body">
-<pre class="sourcelines stripes" data-logurl="{url|urlescape}log/{symrev}/{file|urlescape}">{text%fileline}</pre>
+<pre class="sourcelines stripes" data-logurl="{url|urlescape}log/{symrev}/{file|urlescape}" data-ishead="{ishead}">{text%fileline}</pre>
 </div>
 
 <script type="text/javascript" src="{staticurl|urlescape}followlines.js"></script>
diff -r a457da5296a5 -r a298f5c61b34 mercurial/templates/paper/filerevision.tmpl
--- a/mercurial/templates/paper/filerevision.tmpl	Mon Apr 24 18:33:23 2017 +0200
+++ b/mercurial/templates/paper/filerevision.tmpl	Mon Apr 24 10:32:15 2017 +0200
@@ -71,7 +71,7 @@
 <div class="overflow">
 <div class="sourcefirst linewraptoggle">line wrap: <a class="linewraplink" href="javascript:toggleLinewrap()">on</a></div>
 <div class="sourcefirst"> line source</div>
-<pre class="sourcelines stripes4 wrap bottomline" data-logurl="{url|urlescape}log/{symrev}/{file|urlescape}">{text%fileline}</pre>
+<pre class="sourcelines stripes4 wrap bottomline" data-logurl="{url|urlescape}log/{symrev}/{file|urlescape}" data-ishead="{ishead}">{text%fileline}</pre>
 </div>
 
 <script type="text/javascript" src="{staticurl|urlescape}followlines.js"></script>
diff -r a457da5296a5 -r a298f5c61b34 mercurial/templates/static/followlines.js
--- a/mercurial/templates/static/followlines.js	Mon Apr 24 18:33:23 2017 +0200
+++ b/mercurial/templates/static/followlines.js	Mon Apr 24 10:32:15 2017 +0200
@@ -17,6 +17,8 @@
         return;
     }
 
+    var isHead = parseInt(sourcelines.dataset.ishead || "0");
+
     // tooltip to invite on lines selection
     var tooltip = document.createElement('div');
     tooltip.id = 'followlines-tooltip';
@@ -153,7 +155,7 @@
 
             // append the <div id="followlines"> element to last line of the
             // selection block
-            var divAndButton = followlinesBox(targetUri, startId, endId);
+            var divAndButton = followlinesBox(targetUri, startId, endId, isHead);
             var div = divAndButton[0],
                 button = divAndButton[1];
             inviteElement.appendChild(div);
@@ -186,7 +188,7 @@
     sourcelines.addEventListener('click', lineSelectStart);
 
     //** return a <div id="followlines"> and inner cancel <button> elements */
-    function followlinesBox(targetUri, fromline, toline) {
+    function followlinesBox(targetUri, fromline, toline, isHead) {
         // <div id="followlines">
         var div = document.createElement('div');
         div.id = 'followlines';
@@ -213,13 +215,16 @@
         aAsc.setAttribute('href', url);
         aAsc.textContent = 'ascending';
         aDiv.appendChild(aAsc);
-        var sep = document.createTextNode(' / ');
-        aDiv.appendChild(sep);
-        //     link to "descending" followlines
-        var aDesc = document.createElement('a');
-        aDesc.setAttribute('href', url + '&descend=');
-        aDesc.textContent = 'descending';
-        aDiv.appendChild(aDesc);
+
+        if (!isHead) {
+            var sep = document.createTextNode(' / ');
+            aDiv.appendChild(sep);
+            //     link to "descending" followlines
+            var aDesc = document.createElement('a');
+            aDesc.setAttribute('href', url + '&descend=');
+            aDesc.textContent = 'descending';
+            aDiv.appendChild(aDesc);
+        }
 
         div.appendChild(aDiv);
 
diff -r a457da5296a5 -r a298f5c61b34 tests/test-hgweb-commands.t
--- a/tests/test-hgweb-commands.t	Mon Apr 24 18:33:23 2017 +0200
+++ b/tests/test-hgweb-commands.t	Mon Apr 24 10:32:15 2017 +0200
@@ -1343,7 +1343,7 @@
   <div class="overflow">
   <div class="sourcefirst linewraptoggle">line wrap: <a class="linewraplink" href="javascript:toggleLinewrap()">on</a></div>
   <div class="sourcefirst"> line source</div>
-  <pre class="sourcelines stripes4 wrap bottomline" data-logurl="/log/1/foo">
+  <pre class="sourcelines stripes4 wrap bottomline" data-logurl="/log/1/foo" data-ishead="0">
   <span id="l1">foo</span><a href="#l1"></a></pre>
   </div>
   
@@ -1471,7 +1471,7 @@
   <div class="overflow">
   <div class="sourcefirst linewraptoggle">line wrap: <a class="linewraplink" href="javascript:toggleLinewrap()">on</a></div>
   <div class="sourcefirst"> line source</div>
-  <pre class="sourcelines stripes4 wrap bottomline" data-logurl="/log/2/foo">
+  <pre class="sourcelines stripes4 wrap bottomline" data-logurl="/log/2/foo" data-ishead="1">
   <span id="l1">another</span><a href="#l1"></a></pre>
   </div>
   
diff -r a457da5296a5 -r a298f5c61b34 tests/test-highlight.t
--- a/tests/test-highlight.t	Mon Apr 24 18:33:23 2017 +0200
+++ b/tests/test-highlight.t	Mon Apr 24 10:32:15 2017 +0200
@@ -149,7 +149,7 @@
   <div class="overflow">
   <div class="sourcefirst linewraptoggle">line wrap: <a class="linewraplink" href="javascript:toggleLinewrap()">on</a></div>
   <div class="sourcefirst"> line source</div>
-  <pre class="sourcelines stripes4 wrap bottomline" data-logurl="/log/tip/primes.py">
+  <pre class="sourcelines stripes4 wrap bottomline" data-logurl="/log/tip/primes.py" data-ishead="1">
   <span id="l1"><span class="c">#!/usr/bin/env python</span></span><a href="#l1"></a>
   <span id="l2"></span><a href="#l2"></a>
   <span id="l3"><span class="sd">&quot;&quot;&quot;Fun with generators. Corresponding Haskell implementation:</span></span><a href="#l3"></a>