Added branch and tag support to the git repository viewer. (#1406)

Many thanks to Adam Soltys and everyone else who tested this patch.

* Updated git test repository so it has a branch with some differences from the master branch
* Moved redmine diff class into a module so as not to clash with diff-lcs gem which is required by grit
* Find changesets from all branches, not just master
* Got revision browsing working
* Got file actions working properly
* Allow browsing by short form of commit identifier
* Added a method to retrieve repository branches
* Allow browsing by branch names as well as commit numbers
* Handle the case where a git repository has no master branch
* Expand revision box and handle finding revisions by first 8 characters
* Added branches dropdown to repository show page
* Combined repository browse and show into a single action.  Moved branch/revision navigation into a partial.
* Renamed partial navigation -> breadcrumbs
* Made it so latest revisions list uses branch and path context
* Preserve current path when changing branch or revision
* Perform slightly more graceful error handling in the case of invalid repository URLs
* Allow branch names to contain periods
* Allow dashes in branch names
* Sort branches by name
* Adding tags dropdown
* Need to disable both branches and tags dropdowns before submitting revision form
* Support underscores in revision (branch/tag) names
* Making file history sensitive to current branch/tag/revision, adding common navigation to changes page
* Updated translation files to include labels for 'branch', 'tag', and 'view all revisions'
* Reenable fields after submit so they don't look disabled and don't stay disabled on browser back button
* Instead of dashes just use empty string for default dropdown value
* Individual entry views now sport the upgraded revision navigation
* Don't display dropdowns with no entries
* Consider all revisions when doing initial load
* Fixed bug grabbing changesets.  Thanks to Bernhard Furtmueller for catching.
* Always check the entire log to find new revisions, rather than trying to go forward from the latest known one
* Added some cleverness to avoid selecting the whole changesets table any time someone views the repository root
* File copies and renames being detected properly
* Return gracefully if no revisions are found in the git log
* Applied patch from Babar Le Lapin to improve Windows compatibility

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@2840 e93f8b46-1217-0410-a6f0-8f06a7374b81

2 files changed, 67 insertions, 34 deletions

diff --git a/app/models/repository.rb b/app/models/repository.rb
index bf181bfad..860395b5c 100644
--- a/app/models/repository.rb
+++ b/app/models/repository.rb
@@ -62,6 +62,18 @@ class Repository < ActiveRecord::Base
   def entries(path=nil, identifier=nil)
     scm.entries(path, identifier)
   end
+
+  def branches
+    scm.branches
+  end
+
+  def tags
+    scm.tags
+  end
+
+  def default_branch
+    scm.default_branch
+  end
   
   def properties(path, identifier=nil)
     scm.properties(path, identifier)
@@ -92,11 +104,15 @@ class Repository < ActiveRecord::Base
   def latest_changeset
     @latest_changeset ||= changesets.find(:first)
   end
+
+  def latest_changesets(path,rev,limit=10)
+    @latest_changesets ||= changesets.find(:all, limit, :order => "committed_on DESC")
+  end
     
   def scan_changesets_for_issue_ids
     self.changesets.each(&:scan_comment_for_issue_ids)
   end
-  
+
   # Returns an array of committers usernames and associated user_id
   def committers
     @committers ||= Changeset.connection.select_rows("SELECT DISTINCT committer, user_id FROM #{Changeset.table_name} WHERE repository_id = #{id}")
diff --git a/app/models/repository/git.rb b/app/models/repository/git.rb
index f721b938f..b3cdf3643 100644
--- a/app/models/repository/git.rb
+++ b/app/models/repository/git.rb
@@ -29,43 +29,60 @@ class Repository::Git < Repository
     'Git'
   end
 
+  def branches
+    scm.branches
+  end
+
+  def tags
+    scm.tags
+  end
+
   def changesets_for_path(path, options={})
-    Change.find(:all, :include => {:changeset => :user}, 
-                :conditions => ["repository_id = ? AND path = ?", id, path],
-                :order => "committed_on DESC, #{Changeset.table_name}.revision DESC",
-                :limit => options[:limit]).collect(&:changeset)
+    Change.find(
+      :all, 
+      :include => {:changeset => :user}, 
+      :conditions => ["repository_id = ? AND path = ?", id, path],
+      :order => "committed_on DESC, #{Changeset.table_name}.revision DESC",
+      :limit => options[:limit]
+    ).collect(&:changeset)
   end
 
+  # With SCM's that have a sequential commit numbering, redmine is able to be
+  # clever and only fetch changesets going forward from the most recent one
+  # it knows about.  However, with git, you never know if people have merged
+  # commits into the middle of the repository history, so we always have to
+  # parse the entire log.
   def fetch_changesets
-    scm_info = scm.info
-    if scm_info
-      # latest revision found in database
-      db_revision = latest_changeset ? latest_changeset.revision : nil
-      # latest revision in the repository
-      scm_revision = scm_info.lastrev.scmid
+    # Save ourselves an expensive operation if we're already up to date
+    return if scm.num_revisions == changesets.count
+
+    revisions = scm.revisions('', nil, nil, :all => true)
+    return if revisions.nil? || revisions.empty?
+
+    # Find revisions that redmine knows about already
+    existing_revisions = changesets.find(:all).map!{|c| c.scmid}
+
+    # Clean out revisions that are no longer in git
+    Changeset.delete_all(["scmid NOT IN (?) AND repository_id = (?)", revisions.map{|r| r.scmid}, self.id])
+
+    # Subtract revisions that redmine already knows about
+    revisions.reject!{|r| existing_revisions.include?(r.scmid)}
+
+    # Save the remaining ones to the database
+    revisions.each{|r| r.save(self)} unless revisions.nil?
+  end
+
+  def latest_changesets(path,rev,limit=10)
+    revisions = scm.revisions(path, nil, rev, :limit => limit, :all => false)
+    return [] if revisions.nil? || revisions.empty?
 
-      unless changesets.find_by_scmid(scm_revision)
-        scm.revisions('', db_revision, nil, :reverse => true) do |revision|
-          if changesets.find_by_scmid(revision.scmid.to_s).nil?
-            transaction do
-              changeset = Changeset.create!(:repository => self,
-                                           :revision => revision.identifier,
-                                           :scmid => revision.scmid,
-                                           :committer => revision.author, 
-                                           :committed_on => revision.time,
-                                           :comments => revision.message)
-              
-              revision.paths.each do |change|
-                Change.create!(:changeset => changeset,
-                              :action => change[:action],
-                              :path => change[:path],
-                              :from_path => change[:from_path],
-                              :from_revision => change[:from_revision])
-              end
-            end
-          end
-        end
-      end
-    end
+    changesets.find(
+      :all, 
+      :conditions => [
+        "scmid IN (?)", 
+        revisions.map!{|c| c.scmid}
+      ],
+      :order => 'committed_on DESC'
+    )
   end
 end