This is mostly used when constructing PseudoModules when looking up Instances within other Instances or Definitions. Previously, we would construct the PseudoModule then manually set the _parent field. The problem with this is that _parent is used during construction of the object and defaults to Builder.currentModule. Instead, we properly set the Builder state to hold the desired _parent and then construct the PseudoModule.

This also cleaned up tech debt in Module.do_pseudo_apply which duplicated logic from the standard Module.apply path in a way that had already gotten out of sync and likely would result in other very subtle bugs.

Fixes #5011

Contributor Checklist

• Did you add Scaladoc to every public function/method?
• Did you add at least one test demonstrating the PR?
• Did you delete any extraneous printlns/debugging code?
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Type of Improvement

• Bugfix

Desired Merge Strategy

• Squash

Release Notes

This fixes subtle bugs where accessing children of an Instance (whether directly or by using Select APIs) could change the result of future Select to be incorrect. For example, a call to Select.unsafe.allCurrentInstancesIn could cause Select.unsafe.currentInstancesIn to also incorrectly include grandchildren and all other transitive children.

Reviewer Checklist (only modified by reviewer)

• Did you add the appropriate labels? (Select the most appropriate one based on the "Type of Improvement")
• Did you mark the proper milestone (Bug fix: 3.6.x, 5.x, or 6.x depending on impact, API modification or big change: 7.0)?
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• Did you do one of the following when ready to merge:
  • Squash: You/ the contributor Enable auto-merge (squash) and clean up the commit message.
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