Add copy-to-clipboard button to Snippets#show

Closes #3701

CHANGELOG

@@ -26,6 +26,7 @@ v 8.3.0 (unreleased)
   - Block LDAP user when they are no longer found in the LDAP server
   - Improve wording on project visibility levels (Zeger-Jan van de Weg)
   - Automatically select default clone protocol based on user preferences (Eirik Lygre)
+  - Add copy-to-clipboard button for Snippets
 
 v 8.2.3
   - Fix application settings cache not expiring after changes (Stan Hu)

app/assets/stylesheets/pages/snippets.scss

@@ -32,6 +32,12 @@
   .file-holder {
     border-top: 0;
   }
+
+  .file-actions {
+    .btn-clipboard {
+      @extend .btn;
+    }
+  }
 }
 
 .snippet-box {

app/views/projects/snippets/show.html.haml

@@ -10,7 +10,7 @@
       %strong
         = @snippet.file_name
       .file-actions.hidden-xs
-        .btn-group.tree-btn-group
+        = clipboard_button(clipboard_target: ".blob-content[data-blob-id='#{@snippet.id}']")
         = link_to 'Raw', raw_namespace_project_snippet_path(@project.namespace, @project, @snippet), class: "btn btn-sm", target: "_blank"
 
     = render 'shared/snippets/blob'

app/views/shared/_file_highlight.html.haml

@@ -8,5 +8,6 @@
         %a{href: "#L#{i}", id: "L#{i}", 'data-line-number' => i}
           %i.fa.fa-link
           = i
+  .blob-content{data: {blob_id: blob.id}}
     :preserve
       #{highlight(blob.name, blob.data)}

app/views/snippets/show.html.haml

@@ -9,6 +9,6 @@
       %strong
         = @snippet.file_name
       .file-actions.hidden-xs
-        .btn-group.tree-btn-group
+        = clipboard_button(clipboard_target: ".blob-content[data-blob-id='#{@snippet.id}']")
         = link_to 'Raw', raw_snippet_path(@snippet), class: "btn btn-sm", target: "_blank"
     = render 'shared/snippets/blob'