Assert command refactor

[Lisrte]

Please check if the PR fulfills these requirements

• [x] The commit message follows our guidelines
• [x] Tests for the changes have been added (for bug fixes / features)
• [ ] Docs have been added / updated (for bug fixes / features)

Does this PR already have an issue describing the problem?

No

What kind of change does this PR introduce?

Breaking change fix

What is the current behavior?

What is the new behavior (if this is a feature change)? Implements core PR 3144

Does this PR introduce a breaking change or deprecate an API?

• [ ] Yes
• [x] No

[rolnico]

Covered during #160