Commit Graph

5 Commits (2eff9c8277fbd4e5ad6cbe1a260b2f72872d78ed)

Author SHA1 Message Date
Joe Tsai 350aab05e5
util/multierr: optimize New for nil cases (#6750)
Consider the following pattern:

	err1 := foo()
	err2 := bar()
	err3 := baz()
	return multierr.New(err1, err2, err3)

If err1, err2, and err3 are all nil, then multierr.New should not allocate.
Thus, modify the logic of New to count the number of distinct error values
and allocate the exactly needed slice. This also speeds up non-empty error
situation since repeatedly growing with append is slow.

Performance:

	name         old time/op    new time/op    delta
	Empty-24       41.8ns ± 2%     6.4ns ± 1%   -84.73%  (p=0.000 n=10+10)
	NonEmpty-24     120ns ± 3%      69ns ± 1%   -42.01%  (p=0.000 n=9+10)

	name         old alloc/op   new alloc/op   delta
	Empty-24        64.0B ± 0%      0.0B       -100.00%  (p=0.000 n=10+10)
	NonEmpty-24      168B ± 0%       88B ± 0%   -47.62%  (p=0.000 n=10+10)

	name         old allocs/op  new allocs/op  delta
	Empty-24         1.00 ± 0%      0.00       -100.00%  (p=0.000 n=10+10)
	NonEmpty-24      3.00 ± 0%      2.00 ± 0%   -33.33%  (p=0.000 n=10+10)

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai c47578b528
util/multierr: add Range (#6643)
Errors in Go are no longer viewed as a linear chain, but a tree.
See golang/go#53435.

Add a Range function that iterates through an error
in a pre-order, depth-first order.
This matches the iteration order of errors.As in Go 1.20.

This adds the logic (but currently commented out) for having
Error implement the multi-error version of Unwrap in Go 1.20.
It is commented out currently since it causes "go vet"
to complain about having the "wrong" signature.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Brad Fitzpatrick 116f55ff66 all: gofmt for Go 1.19
Updates #5210

Change-Id: Ib02cd5e43d0a8db60c1f09755a8ac7b140b670be
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Josh Bleecher Snyder 0868329936 all: use any instead of interface{}
My favorite part of generics.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder 3fd5f4380f util/multierr: new package
github.com/go-multierror/multierror served us well.
But we need a few feature from it (implement Is),
and it's not worth maintaining a fork of such a small module.

Instead, I did a clean room implementation inspired by its API.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago