slog: inform ReplaceAttr of groups

Formerly, HandleOptions.ReplaceAttr took only an Attr, so it was
ignorant of the groups that contained the Attr.

This change provides ReplaceAttr with a slice of currently open
groups along with the Attr they contain.

We use a sync.Pool to avoid allocating the group slice in the steady
state.

Also, resolve the Attr's value before passing it to ReplaceAttr.
We need to resolve to determine whether the Attr is a Group,
so let ReplaceAttr benefit from that work.

Change-Id: I9a50e5596f44f93534ce272f0e1681af529fdd94
Reviewed-on: https://go-review.googlesource.com/c/exp/+/455155
Reviewed-by: Alan Donovan <adonovan@google.com>
Run-TryBot: Jonathan Amsterdam <jba@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
5 files changed
tree: bd4c30bacfd562d2879dc79df4d7405aff3e2259
  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
  25. CONTRIBUTING.md
  26. go.mod
  27. go.sum
  28. LICENSE
  29. PATENTS
  30. README.md
README.md

exp

PkgGoDev

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.