As Markus said it is good idea to add #argumentNames to block.
What exactly you want to see at TxText? I ask because Igor make big progress on his design implementation which I think will replace my work totally. So if you want to join his development you don't need my code at all (remove it)
Not totally from what I saw and monday all the tests were green and we published the code because it was the end of a large refactoring to get immutable objects into place and having tests were cool.
When we start a new behavior like copyText we started with tests.
I doubt that all the tests were ever green.
the one of txModel package were because we worked until there were green. So I'm sure about that :)
half of the tests never ran in 3.0: https://ci.inria.fr/pharo-contribution/job/TxText/ Well, might just be a problem of the configuration, but that is hard to guess