Addmod adds a module as a txtar archive to the testdata/mod directory.
Usage:
go run addmod.go path@version...
It should only be used for very small modules - we do not want to check very large files into testdata/mod.
It is acceptable to edit the archive afterward to remove or shorten files. See mod/README for more information.
Savedir archives a directory tree as a txtar archive printed to standard output.
Usage:
go run savedir.go /path/to/dir >saved.txt
Typically the tree is later extracted during a test with tg.extract("testdata/saved.txt").