cmd/txtar: support listing files

This is useful when wanting to round-trip a txtar file by extracting its
files into a new directory and then write the same archive again. We
can't simply read the directory to write the files to a txtar archive
again, as we'll likely just end up with sorted filenames.

That is not often what one wants; for example, for Go tests, it's often
best to keep go.mod at the top. It's also useful to keep an order that
makes sense for the human consuming the file in context.

Now, the roundtrip can be done correctly by listing the files and using
that list again when writing a txtar file back. Note that no variable
expansion happens when listing files, as otherwise it would be
impossible to keep the original variables in our round-trip scenario.

Change-Id: I384cca7ac4ce4dbfb0d3d0f437687b5a2f6298eb
Reviewed-by: Ian Lance Taylor <>
Reviewed-by: Bryan Mills <>
TryBot-Result: Gopher Robot <>
Run-TryBot: Daniel Martí <>
2 files changed
tree: e7973e1c98891828e612521e0a6f25842883b116
  1. apidiff/
  2. cmd/
  3. constraints/
  4. devtools/
  5. ebnf/
  6. ebnflint/
  7. errors/
  8. event/
  9. inotify/
  10. io/
  11. jsonrpc2/
  12. maps/
  13. mmap/
  14. rand/
  15. shiny/
  16. shootout/
  17. slices/
  18. slog/
  19. sumdb/
  20. typeparams/
  21. utf8string/
  22. .gitattributes
  23. .gitignore
  24. codereview.cfg
  26. go.mod
  27. go.sum



This subrepository holds experimental and deprecated (in the old directory) packages.

The idea for this subrepository originated as the pkg/exp directory of the main repository, but its presence there made it unavailable to users of the binary downloads of the Go installation. The subrepository has therefore been created to make it possible to go get these packages.

Warning: Packages here are experimental and unreliable. Some may one day be promoted to the main repository or other subrepository, or they may be modified arbitrarily or even disappear altogether.

In short, code in this subrepository is not subject to the Go 1 compatibility promise. (No subrepo is, but the promise is even more likely to be violated by go.exp than the others.)

Caveat emptor.