[IGN-5933] A Derived tag's self-reference breaks when the tag name is changed

When I use a self-reference ({this}) in the Read Expression of a Derived tag, the reference breaks when I change the name of the tag. I would expect the self-reference to not be dependent on the name.

Last Published Value: [null, Bad_NotFound("Path '[Testing]my_tag.tooltip' not found."), Thu Apr 21 10:31:14 MDT 2022 (1650558674394)]
Quality Diagnostics: Path '[Testing]my_tag.tooltip' not found.

Steps to reproduce:

  1. Create a derived tag
  2. Set source tag path to any other tag
  3. Set Read Expression to {this.tooltip} or any other property
  4. Click Apply
  5. Change the name of the tag

Expression tags don’t have this bug, only Derived tags.

Ignition version 8.1.14

Huh, good catch. If you restart the tag, the reference is fixed, at least.

You’re right. I didn’t realize you could restart a tag.