checksum_support.rb: Add test that checksum is the same on update

Ensure the checksum doesn't change when we save it (and thus call
`#update_checksum`) if the source hasn't changed.

Refs #5416

1 files changed, 8 insertions, 0 deletions

diff --git a/spec/support/checksum_support.rb b/spec/support/checksum_support.rb
index 760955274..f8dffb1b7 100644
--- a/spec/support/checksum_support.rb
+++ b/spec/support/checksum_support.rb
@@ -75,4 +75,12 @@ shared_examples 'checksum support' do
     expect(subject).to receive(:update_checksum).at_least(:once)
     subject.save
   end
+
+  it "doesn't change the checksum on save if the source hasn't been changed" do
+    checksum = subject.checksum
+
+    subject.save
+
+    expect(subject.checksum).to eq(checksum)
+  end
 end