Easy switching between revisions while previewing a file in browser

[pete@…]

While previewing a file in the browser it is helpful to be able to quickly jump back and forth between revisions. Attatched is a patch to the current /trunk/versioncontrol/web/browser.py to add links to the oldest, previous, next, and most recent revisions to a file being previewed. I'm not familiar with hacking the templates, so the links simply appear in the 'alternate' file downloads area.

--- browser.py	2006-01-04 10:16:03.000000000 -0500
+++ browser.py	2006-01-04 10:19:30.000000000 -0500
@@ -25,6 +25,7 @@
 from trac.web.chrome import add_link, add_stylesheet, INavigationContributor
 from trac.wiki import wiki_to_html, wiki_to_oneliner, IWikiSyntaxProvider
 from trac.versioncontrol.web_ui.util import *
+from trac.versioncontrol.svn_authz import SubversionAuthorizer
 
 
 IMG_RE = re.compile(r"\.(gif|jpg|jpeg|png)(\?.*)?$", re.IGNORECASE)
@@ -211,6 +212,34 @@
             mime_type = get_mime_type(content)
             use_rev = rev and node.rev
             
+            newestchgset = repos.get_youngest_rev()
+            nodehistory = repos.get_path_history(node.path, newestchgset)
+            allrevs = list(nodehistory)
+            oldest_rev_num = len(allrevs) - 1
+            oldest_rev = allrevs[oldest_rev_num]
+            oldest_path = '%s' % oldest_rev[0]
+            youngest_rev = allrevs[0]
+            youngest_path = '%s' % youngest_rev[0]
+            temprev = 0
+       ##find the current rev     
+            for revision in allrevs:
+            	if revision[1] == int(node.rev):
+            		break
+            	else:
+            		temprev += 1
+            		continue
+           		
+            current_rev = allrevs[temprev]
+            
+            if current_rev != oldest_rev:
+            	previous_rev = allrevs[temprev + 1]
+            	prev_path = '%s' % previous_rev[0]
+            	if previous_rev != oldest_rev:
+	             	add_link(req, 'alternate', self.env.href.browser(oldest_path, rev=oldest_rev[1]), 'Oldest Revision')
+	             	add_link(req, 'alternate', self.env.href.browser(prev_path, rev=previous_rev[1]), 'Previous Revision')
+                else:
+	             	add_link(req, 'alternate', self.env.href.browser(oldest_path, rev=oldest_rev[1]), 'Previous (Oldest) Revision')
+            
             if not is_binary(content):
                 if mime_type != 'text/plain':
                     plain_href = self.env.href.browser(node.path, rev=use_rev,
@@ -230,6 +259,16 @@
             add_link(req, 'alternate', raw_href, 'Original Format', mime_type)
             req.hdf['file.raw_href'] = raw_href
 
+            if current_rev != youngest_rev:
+            	next_rev = allrevs[temprev - 1]
+            	next_path = '%s' % next_rev[0]
+                if temprev - 1 > 0 and next_rev != youngest_rev:
+	             	add_link(req, 'alternate', self.env.href.browser(next_path, rev=next_rev[1]), 'Next Revision')
+	             	add_link(req, 'alternate', self.env.href.browser(youngest_path, rev=youngest_rev[1]), 'Most Recent Revision')
+                else:
+	             	add_link(req, 'alternate', self.env.href.browser(youngest_path, rev=youngest_rev[1]), 'Next (Most Recent) Revision')
+
+
             add_stylesheet(req, 'common/css/code.css')
 
     # IWikiSyntaxProvider methods

[Christopher Lenz]

Using diff to compare versions sounds like a better idea to me. Anyway, no enhancements on the maintenance branch.

[Christian Boos]

The trunk has now this feature, since the merging of the TracDiff branch.

See TracChangeset#CheckingtheLastChange.

[Christian Boos]

PS: also, in the patch, the usage of repos.get_path_history() seems to be quite inappropriate here. That method has a very specific usage and should be used only in some situations (it's actually used to implement the Show only add, removes mode of TracRevisionLog, and for the search link shown in the TracBrowser when a path is not found). You should have used simply Repository.get_node() then Node.get_history().

I also realize that the documentation for this method is misleading… I'll fix that.