1 files changed, 60 insertions, 0 deletions
diff --git a/app/assets/javascripts/pages/projects/merge_requests/creations/new/compare.js b/app/assets/javascripts/pages/projects/merge_requests/creations/new/compare.js
new file mode 100644
index 00000000000..46f3f55a400
--- /dev/null
+++ b/app/assets/javascripts/pages/projects/merge_requests/creations/new/compare.js
@@ -0,0 +1,60 @@
+import $ from 'jquery';
+import { localTimeAgo } from '~/lib/utils/datetime_utility';
+import axios from '~/lib/utils/axios_utils';
+import initCompareAutocomplete from '~/compare_autocomplete';
+import initTargetProjectDropdown from './target_project_dropdown';
+
+const updateCommitList = (url, $loadingIndicator, $commitList, params) => {
+  $loadingIndicator.show();
+  $commitList.empty();
+
+  return axios
+    .get(url, {
+      params,
+    })
+    .then(({ data }) => {
+      $loadingIndicator.hide();
+      $commitList.html(data);
+      localTimeAgo($('.js-timeago', $commitList));
+    });
+};
+
+export default mrNewCompareNode => {
+  const { sourceBranchUrl, targetBranchUrl } = mrNewCompareNode.dataset;
+  initTargetProjectDropdown();
+
+  const updateSourceBranchCommitList = () =>
+    updateCommitList(
+      sourceBranchUrl,
+      $(mrNewCompareNode).find('.js-source-loading'),
+      $(mrNewCompareNode).find('.mr_source_commit'),
+      {
+        ref: $(mrNewCompareNode)
+          .find("input[name='merge_request[source_branch]']")
+          .val(),
+      },
+    );
+  const updateTargetBranchCommitList = () =>
+    updateCommitList(
+      targetBranchUrl,
+      $(mrNewCompareNode).find('.js-target-loading'),
+      $(mrNewCompareNode).find('.mr_target_commit'),
+      {
+        target_project_id: $(mrNewCompareNode)
+          .find("input[name='merge_request[target_project_id]']")
+          .val(),
+        ref: $(mrNewCompareNode)
+          .find("input[name='merge_request[target_branch]']")
+          .val(),
+      },
+    );
+  initCompareAutocomplete('branches', $dropdown => {
+    if ($dropdown.is('.js-target-branch')) {
+      updateTargetBranchCommitList();
+    } else if ($dropdown.is('.js-source-branch')) {
+      updateSourceBranchCommitList();
+    }
+  });
+  updateSourceBranchCommitList();
+  updateTargetBranchCommitList();
+};