tree e878c2cb3ad536f08638cffe27be09eae8c22750
parent 58fedf60c6b1b72e6adf6224d45ebbab7d6ba64e
author Russ Cox <rsc@golang.org> 1683090444 -0400
committer Russ Cox <rsc@golang.org> 1683247562 +0000

bisect, cmd/bisect: add new library and tool

cmd/bisect automates culprit finding in a large set of
independent changes that together provoke a failure
(either when all enabled or when all disabled, but not both).
By repeating a target command with different subsets of
the changes enabled, bisect identifies the smallest number
of changes that need to be toggled away from the passing
state to cause the failing state.

Package bisect provides functionality to help target commands that
want to support running under cmd/bisect.

This is based on work done by khr and drchase in the Go compiler
and by drchase in github.com/dr2chase/gossahash,
but generalized to support other kinds of targets and
simplify the invocation.

This tool will be useful for finding call sites where a GODEBUG
setting changes a test outcome, as well as source code locations
where applying per-iteration loop semantics changes a test outcome.

Package bisect could use some direct tests of its own, but it is tested
quite a bit via the cmd/bisect test.

Change-Id: Id29efad9936bebee17c1475d92cb167019905aa4
Reviewed-on: https://go-review.googlesource.com/c/tools/+/491875
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
gopls-CI: kokoro <noreply+kokoro@google.com>
Reviewed-by: David Chase <drchase@google.com>