hgweb: display diff for a changeset against any parents (issue2810)

hgweb: display diff for a changeset against any parents (issue2810)

During merge of branches, it is useful to compare merge results against
the two parents.  This change adds this support to hgweb.  To specify
which parent to compare to, use rev/12300:12345 where 12300 is a
parent changeset number.  Two links are added to changeset web page so
that one can choose which parent to compare to.

--- a/mercurial/hgweb/webcommands.py	Thu Nov 29 08:49:21 2012 -0500
+++ b/mercurial/hgweb/webcommands.py	Mon Nov 12 14:05:39 2012 -0800
@@ -256,6 +256,9 @@
 
 def changeset(web, req, tmpl):
     ctx = webutil.changectx(web.repo, req)
+    basectx = webutil.basechangectx(web.repo, req)
+    if basectx is None:
+        basectx = ctx.p1()
     showtags = webutil.showtag(web.repo, tmpl, 'changesettag', ctx.node())
     showbookmarks = webutil.showbookmark(web.repo, tmpl, 'changesetbookmark',
                                          ctx.node())
@@ -274,10 +277,10 @@
         style = req.form['style'][0]
 
     parity = paritygen(web.stripecount)
-    diffs = webutil.diffs(web.repo, tmpl, ctx, None, parity, style)
+    diffs = webutil.diffs(web.repo, tmpl, ctx, basectx, None, parity, style)
 
     parity = paritygen(web.stripecount)
-    diffstatgen = webutil.diffstatgen(ctx)
+    diffstatgen = webutil.diffstatgen(ctx, basectx)
     diffstat = webutil.diffstat(tmpl, ctx, diffstatgen, parity)
 
     return tmpl('changeset',
@@ -286,6 +289,7 @@
                 node=ctx.hex(),
                 parent=webutil.parents(ctx),
                 child=webutil.children(ctx),
+                currentbaseline=basectx.hex(),
                 changesettag=showtags,
                 changesetbookmark=showbookmarks,
                 changesetbranch=showbranch,
@@ -567,7 +571,7 @@
     if 'style' in req.form:
         style = req.form['style'][0]
 
-    diffs = webutil.diffs(web.repo, tmpl, ctx, [path], parity, style)
+    diffs = webutil.diffs(web.repo, tmpl, ctx, None, [path], parity, style)
     rename = fctx and webutil.renamelink(fctx) or []
     ctx = fctx and fctx or ctx
     return tmpl("filediff",

--- a/mercurial/hgweb/webutil.py	Thu Nov 29 08:49:21 2012 -0500
+++ b/mercurial/hgweb/webutil.py	Mon Nov 12 14:05:39 2012 -0800
@@ -140,13 +140,7 @@
     path = path.lstrip('/')
     return scmutil.canonpath(repo.root, '', path)
 
-def changectx(repo, req):
-    changeid = "tip"
-    if 'node' in req.form:
-        changeid = req.form['node'][0]
-    elif 'manifest' in req.form:
-        changeid = req.form['manifest'][0]
-
+def changeidctx (repo, changeid):
     try:
         ctx = repo[changeid]
     except error.RepoError:
@@ -155,6 +149,28 @@
 
     return ctx
 
+def changectx (repo, req):
+    changeid = "tip"
+    if 'node' in req.form:
+        changeid = req.form['node'][0]
+        ipos=changeid.find(':')
+        if ipos != -1:
+            changeid = changeid[(ipos + 1):]
+    elif 'manifest' in req.form:
+        changeid = req.form['manifest'][0]
+
+    return changeidctx(repo, changeid)
+
+def basechangectx(repo, req):
+    if 'node' in req.form:
+        changeid = req.form['node'][0]
+        ipos=changeid.find(':')
+        if ipos != -1:
+            changeid = changeid[:ipos]
+            return changeidctx(repo, changeid)
+
+    return None
+
 def filectx(repo, req):
     if 'file' not in req.form:
         raise ErrorResponse(HTTP_NOT_FOUND, 'file not given')
@@ -178,7 +194,7 @@
     if len(files) > max:
         yield tmpl('fileellipses')
 
-def diffs(repo, tmpl, ctx, files, parity, style):
+def diffs(repo, tmpl, ctx, basectx, files, parity, style):
 
     def countgen():
         start = 1
@@ -209,8 +225,11 @@
         m = match.always(repo.root, repo.getcwd())
 
     diffopts = patch.diffopts(repo.ui, untrusted=True)
-    parents = ctx.parents()
-    node1 = parents and parents[0].node() or nullid
+    if basectx is None:
+        parents = ctx.parents()
+        node1 = parents and parents[0].node() or nullid
+    else:
+        node1 = basectx.node()
     node2 = ctx.node()
 
     block = []
@@ -274,10 +293,10 @@
         for oc in s.get_grouped_opcodes(n=context):
             yield tmpl('comparisonblock', lines=getblock(oc))
 
-def diffstatgen(ctx):
+def diffstatgen(ctx, basectx):
     '''Generator function that provides the diffstat data.'''
 
-    stats = patch.diffstatdata(util.iterlines(ctx.diff()))
+    stats = patch.diffstatdata(util.iterlines(ctx.diff(basectx)))
     maxname, maxtotal, addtotal, removetotal, binary = patch.diffstatsum(stats)
     while True:
         yield stats, maxname, maxtotal, addtotal, removetotal, binary

--- a/mercurial/templater.py	Thu Nov 29 08:49:21 2012 -0500
+++ b/mercurial/templater.py	Mon Nov 12 14:05:39 2012 -0800
@@ -184,6 +184,7 @@
     for i in d:
         if isinstance(i, dict):
             lm.update(i)
+            lm['originalnode'] = mapping.get('node')
             yield runtemplate(context, lm, ctmpl)
         else:
             # v is not an iterable of dicts, this happen when 'key'

--- a/mercurial/templates/paper/changeset.tmpl	Thu Nov 29 08:49:21 2012 -0500
+++ b/mercurial/templates/paper/changeset.tmpl	Mon Nov 12 14:05:39 2012 -0800
@@ -74,6 +74,14 @@
     </div>
   </td>
 </tr>
+<tr>
+ <th class="author">change baseline</th>
+ <td class="author">{parent%changesetbaseline}</td>
+</tr>
+<tr>
+ <th class="author">current baseline</th>
+ <td class="author"><a href="{url}rev/{currentbaseline|short}{sessionvars%urlparameter}">{currentbaseline|short}</a></td>
+</tr>
 </table>
 
 <div class="overflow">

--- a/mercurial/templates/paper/map	Thu Nov 29 08:49:21 2012 -0500
+++ b/mercurial/templates/paper/map	Mon Nov 12 14:05:39 2012 -0800
@@ -101,6 +101,8 @@
 
 changesetparent = '<a href="{url}rev/{node|short}{sessionvars%urlparameter}">{node|short}</a> '
 
+changesetbaseline = '<a href="{url}rev/{node|short}:{originalnode|short}{sessionvars%urlparameter}">{node|short}</a> '
+
 filerevparent = '<a href="{url}file/{node|short}/{file|urlescape}{sessionvars%urlparameter}">{rename%filerename}{node|short}</a> '
 filerevchild = '<a href="{url}file/{node|short}/{file|urlescape}{sessionvars%urlparameter}">{node|short}</a> '
 

--- a/tests/test-hgweb-commands.t	Thu Nov 29 08:49:21 2012 -0500
+++ b/tests/test-hgweb-commands.t	Mon Nov 12 14:05:39 2012 -0800
@@ -441,6 +441,14 @@
       </div>
     </td>
   </tr>
+  <tr>
+   <th class="author">change baseline</th>
+   <td class="author"></td>
+  </tr>
+  <tr>
+   <th class="author">current baseline</th>
+   <td class="author"><a href="/rev/000000000000">000000000000</a></td>
+  </tr>
   </table>
   
   <div class="overflow">

--- a/tests/test-hgweb-diffs.t	Thu Nov 29 08:49:21 2012 -0500
+++ b/tests/test-hgweb-diffs.t	Mon Nov 12 14:05:39 2012 -0800
@@ -139,6 +139,14 @@
       </div>
     </td>
   </tr>
+  <tr>
+   <th class="author">change baseline</th>
+   <td class="author"></td>
+  </tr>
+  <tr>
+   <th class="author">current baseline</th>
+   <td class="author"><a href="/rev/000000000000">000000000000</a></td>
+  </tr>
   </table>
   
   <div class="overflow">
@@ -400,6 +408,14 @@
       </div>
     </td>
   </tr>
+  <tr>
+   <th class="author">change baseline</th>
+   <td class="author"></td>
+  </tr>
+  <tr>
+   <th class="author">current baseline</th>
+   <td class="author"><a href="/rev/000000000000">000000000000</a></td>
+  </tr>
   </table>
   
   <div class="overflow">

--- a/tests/test-hgweb-removed.t	Thu Nov 29 08:49:21 2012 -0500
+++ b/tests/test-hgweb-removed.t	Mon Nov 12 14:05:39 2012 -0800
@@ -112,6 +112,14 @@
       </div>
     </td>
   </tr>
+  <tr>
+   <th class="author">change baseline</th>
+   <td class="author"><a href="/rev/cb9a9f314b8b:c78f6c5cbea9">cb9a9f314b8b</a> </td>
+  </tr>
+  <tr>
+   <th class="author">current baseline</th>
+   <td class="author"><a href="/rev/cb9a9f314b8b">cb9a9f314b8b</a></td>
+  </tr>
   </table>
   
   <div class="overflow">