Compare branches, commits and tags with each other (#6991)

* Supports tags when comparing commits or branches

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Hide headline when only comparing and don't load unused data

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Merges compare logics to allow comparing branches, commits and tags with eachother

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Display branch or tag instead of commit when used for comparing

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Show pull request form after click on button

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Transfers relevant pull.go changes from master to compare.go

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Fixes error when comparing forks against a commit or tag

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Removes console.log from JavaScript file

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Show icon next to commit reference when comparing branch or tag

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Updates css file

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Fixes import order

* Renames template variable

* Update routers/repo/compare.go

Co-Authored-By: zeripath <art27@cantab.net>

* Update from master

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Allow short-shas in compare

* Renames prInfo to compareInfo

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Check PR permissions only if compare is pull request

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Adjusts comment

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Use compareInfo instead of prInfo

3 files changed, 12 insertions, 1 deletions

diff --git a/public/css/index.css b/public/css/index.css
index 8950cc7038..d192f43d15 100644
--- a/public/css/index.css
+++ b/public/css/index.css
@@ -591,6 +591,7 @@ footer .ui.left,footer .ui.right{line-height:40px}
 .repository .milestone.list>.item .content{padding-top:10px}
 .repository.new.milestone textarea{height:200px}
 .repository.new.milestone #deadline{width:150px}
+.repository.compare.pull .show-form-container{text-align:left}
 .repository.compare.pull .choose.branch .octicon{padding-right:10px}
 .repository.compare.pull .comment.form .content:after,.repository.compare.pull .comment.form .content:before{right:100%;top:20px;border:solid transparent;content:" ";height:0;width:0;position:absolute;pointer-events:none}
 .repository.compare.pull .comment.form .content:before{border-right-color:#d3d3d4;border-width:9px;margin-top:-9px}
diff --git a/public/js/index.js b/public/js/index.js
index ed3198594a..28023e1061 100644
--- a/public/js/index.js
+++ b/public/js/index.js
@@ -959,8 +959,15 @@ function initRepository() {
     });
 
     // Pull request
-    if ($('.repository.compare.pull').length > 0) {
+    var $repoComparePull = $('.repository.compare.pull');
+    if ($repoComparePull.length > 0) {
         initFilterSearchDropdown('.choose.branch .dropdown');
+        // show pull request form
+        $repoComparePull.find('button.show-form').on('click', function(e) {
+            e.preventDefault();
+            $repoComparePull.find('.pullrequest-form').show();
+            $(this).parent().hide();
+        });
     }
 
     // Branches
diff --git a/public/less/_repository.less b/public/less/_repository.less
index 9956bbce74..fcc153e31e 100644
--- a/public/less/_repository.less
+++ b/public/less/_repository.less
@@ -1109,6 +1109,9 @@
     }
 
     &.compare.pull {
+        .show-form-container {
+            text-align: left;
+        }
         .choose.branch {
             .octicon {
                 padding-right: 10px;