Merge branch 'changelog-link' into 'master'

Add changelog, license and contribution guide links to project sidebar.

If the version is known, the "Version: 7.9.0pre" button links to the changelog, otherwise a "View changelog" button is shown.

![Screen_Shot_2015-03-18_at_14.22.29](https://dev.gitlab.org/gitlab/gitlabhq/uploads/747acc018ec9a188098e0f0bc4e91cc3/Screen_Shot_2015-03-18_at_14.22.29.png)

See merge request !1708

6 files changed, 105 insertions, 41 deletions

diff --git a/app/helpers/projects_helper.rb b/app/helpers/projects_helper.rb
index 2225b110651..a14277180c7 100644
--- a/app/helpers/projects_helper.rb
+++ b/app/helpers/projects_helper.rb
@@ -232,12 +232,45 @@ module ProjectsHelper
   end
 
   def contribution_guide_url(project)
-    if project && project.repository.contribution_guide
+    if project && contribution_guide = project.repository.contribution_guide
       namespace_project_blob_path(
         project.namespace,
         project,
         tree_join(project.default_branch,
-                  project.repository.contribution_guide.name)
+                  contribution_guide.name)
+      )
+    end
+  end
+
+  def changelog_url(project)
+    if project && changelog = project.repository.changelog
+      namespace_project_blob_path(
+        project.namespace,
+        project,
+        tree_join(project.default_branch,
+                  changelog.name)
+      )
+    end
+  end
+
+  def license_url(project)
+    if project && license = project.repository.license
+      namespace_project_blob_path(
+        project.namespace,
+        project,
+        tree_join(project.default_branch,
+                  license.name)
+      )
+    end
+  end
+
+  def version_url(project)
+    if project && version = project.repository.version
+      namespace_project_blob_path(
+        project.namespace,
+        project,
+        tree_join(project.default_branch,
+                  version.name)
       )
     end
   end
diff --git a/app/models/repository.rb b/app/models/repository.rb
index 7addbca8fb1..c6eaa485b8a 100644
--- a/app/models/repository.rb
+++ b/app/models/repository.rb
@@ -122,7 +122,7 @@ class Repository
 
   def expire_cache
     %i(size branch_names tag_names commit_count graph_log
-       readme version contribution_guide).each do |key|
+       readme version contribution_guide changelog license).each do |key|
       cache.expire(key)
     end
   end
@@ -211,7 +211,27 @@ class Repository
   end
 
   def contribution_guide
-    cache.fetch(:contribution_guide) { tree(:head).contribution_guide }
+    cache.fetch(:contribution_guide) do
+      tree(:head).blobs.find do |file|
+        file.contributing?
+      end
+    end
+  end
+
+  def changelog
+    cache.fetch(:changelog) do
+      tree(:head).blobs.find do |file|
+        file.name =~ /^(changelog|history)/i
+      end
+    end
+  end
+
+  def license
+    cache.fetch(:license) do
+      tree(:head).blobs.find do |file|
+        file.name =~ /^license/i
+      end
+    end
   end
 
   def head_commit
diff --git a/app/models/tree.rb b/app/models/tree.rb
index 4f5d81f0a5e..f279e896cda 100644
--- a/app/models/tree.rb
+++ b/app/models/tree.rb
@@ -1,38 +1,38 @@
 class Tree
   include Gitlab::MarkdownHelper
 
-  attr_accessor :entries, :readme, :contribution_guide
+  attr_accessor :repository, :sha, :path, :entries
 
   def initialize(repository, sha, path = '/')
     path = '/' if path.blank?
-    git_repo = repository.raw_repository
-    @entries = Gitlab::Git::Tree.where(git_repo, sha, path)
-
-    available_readmes = @entries.select(&:readme?)
-
-    if available_readmes.count > 0
-      # If there is more than 1 readme in tree, find readme which is supported
-      # by markup renderer.
-      if available_readmes.length > 1
-        supported_readmes = available_readmes.select do |readme|
-          previewable?(readme.name)
-        end
-
-        # Take the first supported readme, or the first available readme, if we
-        # don't support any of them
-        readme_tree = supported_readmes.first || available_readmes.first
-      else
-        readme_tree = available_readmes.first
-      end
-
-      readme_path = path == '/' ? readme_tree.name : File.join(path, readme_tree.name)
-      @readme = Gitlab::Git::Blob.find(git_repo, sha, readme_path)
-    end
+    
+    @repository = repository
+    @sha = sha
+    @path = path
+
+    git_repo = @repository.raw_repository
+    @entries = Gitlab::Git::Tree.where(git_repo, @sha, @path)
+  end
+
+  def readme
+    return @readme if defined?(@readme)
 
-    if contribution_tree = @entries.find(&:contributing?)
-      contribution_path = path == '/' ? contribution_tree.name : File.join(path, contribution_tree.name)
-      @contribution_guide = Gitlab::Git::Blob.find(git_repo, sha, contribution_path)
+    available_readmes = blobs.select(&:readme?)
+
+    if available_readmes.count == 0
+      return @readme = nil 
     end
+
+    # Take the first previewable readme, or the first available readme, if we
+    # can't preview any of them
+    readme_tree = available_readmes.find do |readme|
+      previewable?(readme.name)
+    end || available_readmes.first
+
+    readme_path = path == '/' ? readme_tree.name : File.join(path, readme_tree.name)
+
+    git_repo = repository.raw_repository
+    @readme = Gitlab::Git::Blob.find(git_repo, sha, readme_path)
   end
 
   def trees
diff --git a/app/views/projects/_issuable_form.html.haml b/app/views/projects/_issuable_form.html.haml
index a7cd129b631..7fd5fe8a6e1 100644
--- a/app/views/projects/_issuable_form.html.haml
+++ b/app/views/projects/_issuable_form.html.haml
@@ -71,10 +71,10 @@
       = link_to 'Create new label', new_namespace_project_label_path(issuable.project.namespace, issuable.project), target: :blank
 
 .form-actions
-  - if !issuable.project.empty_repo? && contribution_guide_url(issuable.project) && !issuable.persisted?
+  - if !issuable.project.empty_repo? && (guide_url = contribution_guide_url(issuable.project)) && !issuable.persisted?
     %p
       Please review the
-      %strong #{link_to 'guidelines for contribution', contribution_guide_url(issuable.project)}
+      %strong #{link_to 'guidelines for contribution', guide_url}
       to this repository.
   - if issuable.new_record?
     = f.submit "Submit new #{issuable.class.model_name.human.downcase}", class: 'btn btn-create'
diff --git a/app/views/projects/merge_requests/_new_submit.html.haml b/app/views/projects/merge_requests/_new_submit.html.haml
index bf80afe8785..1d8eef4e8ce 100644
--- a/app/views/projects/merge_requests/_new_submit.html.haml
+++ b/app/views/projects/merge_requests/_new_submit.html.haml
@@ -69,10 +69,10 @@
           = link_to 'Create new label', new_namespace_project_label_path(@merge_request.target_project.namespace, @merge_request.target_project), target: :blank
 
     .form-actions
-      - if contribution_guide_url(@target_project)
+      - if guide_url = contribution_guide_url(@target_project)
         %p
           Please review the
-          %strong #{link_to 'guidelines for contribution', contribution_guide_url(@target_project)}
+          %strong #{link_to 'guidelines for contribution', guide_url}
           to this repository.
       = f.hidden_field :source_project_id
       = f.hidden_field :source_branch
diff --git a/app/views/projects/show.html.haml b/app/views/projects/show.html.haml
index 74b07395650..822e67c5616 100644
--- a/app/views/projects/show.html.haml
+++ b/app/views/projects/show.html.haml
@@ -47,15 +47,26 @@
               = link_to @project.forked_from_project.name_with_namespace, namespace_project_path(@project.namespace, @project.forked_from_project)
 
           - unless @project.empty_repo?
-            = link_to namespace_project_compare_index_path(@project.namespace, @project, from: @repository.root_ref, to: @ref || @repository.root_ref), class: 'btn btn-block' do
-              Compare code
-
-            - if @repository.version
-              - version = @repository.version
-              = link_to namespace_project_blob_path(@project.namespace, @project, tree_join(@repository.root_ref, version.name)), class: 'btn btn-block' do
+            - if version = @repository.version
+              - detail_url = changelog_url(@project) || version_url(@project)
+              = link_to detail_url, class: 'btn btn-block' do
                 Version:
                 %span.count
                   = @repository.blob_by_oid(version.id).data
+            - elsif @repository.changelog
+              = link_to changelog_url(@project), class: 'btn btn-block' do
+                View changelog
+
+            - if @repository.contribution_guide
+              = link_to contribution_guide_url(@project), class: 'btn btn-block' do
+                View contribution guide
+
+            - if @repository.license
+              = link_to license_url(@project), class: 'btn btn-block' do
+                View license
+            
+            = link_to namespace_project_compare_index_path(@project.namespace, @project, from: @repository.root_ref, to: @ref || @repository.root_ref), class: 'btn btn-block' do
+              Compare code
 
         .prepend-top-10
           %p