Move conditional inside copy_blob_source_button

app/helpers/blob_helper.rb

@@ -208,10 +208,10 @@ module BlobHelper
     clipboard_button(text: file_path, gfm: "`#{file_path}`", class: 'btn-clipboard btn-transparent prepend-left-5', title: 'Copy file path to clipboard')
   end
 
-  def copy_blob_content_button(blob)
-    return if markup?(blob.name)
+  def copy_blob_source_button(blob)
+    return unless blob.rendered_as_text?(override_max_size: params[:override_max_size])
 
-    clipboard_button(target: ".blob-content[data-blob-id='#{blob.id}']", class: "btn btn-sm", title: "Copy content to clipboard")
+    clipboard_button(target: ".blob-content[data-blob-id='#{blob.id}']", class: "btn btn-sm js-copy-blob-source-btn", title: "Copy source to clipboard")
   end
 
   def open_raw_file_button(path)

app/views/projects/blob/_header.html.haml

@@ -13,7 +13,7 @@
 
   .file-actions.hidden-xs
     .btn-group{ role: "group" }<
-      = copy_blob_content_button(blob) if !blame && blob_rendered_as_text?(blob)
+      = copy_blob_source_button(blob) unless blame
       = open_raw_file_button(namespace_project_raw_path(@project.namespace, @project, @id))
       = view_on_environment_button(@commit.sha, @path, @environment) if @environment