Fix collapsed files not fully fully expanding

This fixes files that are collapsed by default not expanding
when the expand all button is clicked.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/53866

1 files changed, 22 insertions, 0 deletions

diff --git a/spec/javascripts/diffs/components/diff_file_spec.js b/spec/javascripts/diffs/components/diff_file_spec.js
index 882ad3685a2..431944eee96 100644
--- a/spec/javascripts/diffs/components/diff_file_spec.js
+++ b/spec/javascripts/diffs/components/diff_file_spec.js
@@ -107,4 +107,26 @@ describe('DiffFile', () => {
       });
     });
   });
+
+  describe('watch collapsed', () => {
+    it('calls handleLoadCollapsedDiff if collapsed changed & file has no lines', done => {
+      spyOn(vm, 'handleLoadCollapsedDiff');
+
+      vm.file.highlightedDiffLines = undefined;
+      vm.file.parallelDiffLines = [];
+      vm.file.collapsed = true;
+
+      vm.$nextTick()
+        .then(() => {
+          vm.file.collapsed = false;
+
+          return vm.$nextTick();
+        })
+        .then(() => {
+          expect(vm.handleLoadCollapsedDiff).toHaveBeenCalled();
+        })
+        .then(done)
+        .catch(done.fail);
+    });
+  });
 });