Bryan C. Mills 4b43d668c2 internal/testenv: avoid rebuilding all of std in WriteImportcfg ... Instead, have the caller pass in an explicit list of the packages (if any) they need. After #47257, a builder running a test does not necessarily have the entire standard library already cached, especially when running tests in sharded mode. testenv.WriteImportcfg used to write an importcfg for the entire standard library — which required rebuilding the entire standard library — even though most tests need only a tiny subset. This reduces the time to test internal/abi with a cold build cache on my workstation from ~16s to ~0.05s. It somewhat increases the time for 'go test go/internal/gcimporter' with a cold cache, from ~43s to ~54s, presumably due to decreased parallelism in rebuilding the standard library and increased overhead in re-resolving the import map. However, 'go test -short' running time remains stable (~5.5s before and after). Fixes #58248. Change-Id: I9be6b61ae6e28b75b53af85207c281bb93b9346f Reviewed-on: https://go-review.googlesource.com/c/go/+/464736 Run-TryBot: Bryan Mills <bcmills@google.com> Reviewed-by: Cherry Mui <cherryyz@google.com> Reviewed-by: Than McIntosh <thanm@google.com> TryBot-Result: Gopher Robot <gobot@golang.org> Auto-Submit: Bryan Mills <bcmills@google.com>		2023-02-02 19:27:33 +00:00
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gc.go	cmd/go: do not confuse files for standard library packages	2023-01-17 22:30:23 +00:00
gccgo.go	…