tree 70a07ba7df0923ff87a1eb3d2d37f9c65964b222
parent 2e794c2bb1302af764670dba894bbfe537bd63f0
author Jay Conrod <jayconrod@google.com> 1614807022 -0500
committer Jay Conrod <jayconrod@google.com> 1614958071 +0000

cmd/go/internal/modfetch: detect and recover from missing ziphash file

Previously, if an extracted module directory existed in the module
cache, but the corresponding ziphash file did not, if the sum was
missing from go.sum, we would not verify the sum. This caused 'go get'
not to write missing sums. 'go build' in readonly mode (now the
default) checks for missing sums and doesn't attempt to fetch modules
that can't be verified against go.sum.

With this change, when requesting the module directory with
modfetch.DownloadDir, if the ziphash file is missing, the go command
will re-hash the zip without downloading or re-extracting it again.

Note that the go command creates the ziphash file before the module
directory, but another program could remove it separately, and it
might not be present after a crash.

Fixes #44749

Change-Id: I64551e048a3ba17d069de1ec123d5b8b2757543c
Reviewed-on: https://go-review.googlesource.com/c/go/+/298352
Trust: Jay Conrod <jayconrod@google.com>
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>