From a3426f2571bc6f6e55f70ad7a0e7198ecdeb10e4 Mon Sep 17 00:00:00 2001 From: "Bryan C. Mills" Date: Tue, 24 Sep 2019 10:46:08 -0400 Subject: [PATCH] cmd/go: suppress errors in package-to-module queries if the package is already found MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In CL 173017, I changed the package-to-module query logic to query all possible module paths in parallel in order to reduce latency. (For long package paths, most such paths will not exist and will fail with little overhead.) The module resolution algorithm treats various kinds of non-existence as “soft errors”, to be reported only if package resolution fails, but treats any remaining errors as hard errors that should fail the query. Unfortunately, that interacted badly with the +incompatible version validation added in CL 181881, causing a regression in the 'direct' fetch path for modules using the “major branch” layout¹ with a post-v1 version on the repository's default branch. Because we did not interpret a mismatched module path as “no such module”, a go.mod file specifying the path 'example.com/foo/v2' would cause the search for module 'example.com/foo' to error out. (That regression was not caught ahead of time due to a lack of test coverage for 'go get' on a package within a /vN module.) The promotion of hard errors during parallel search also made the 'go' command less tolerant of servers that advertise 'go-import' tags for nonexistent repositories. CL 194561 mitigated that problem for HTTP servers that return code 404 or 410 for a nonexistent repository, but unfortunately a few servers in common use (notably GitLab and pre-1.9.3 releases of Gitea) do not. This change mitigates both of those failure modes by ignoring “miscellaneous” errors from shorter module paths if the requested package pattern was successfully matched against a module with a longer path. ¹https://research.swtch.com/vgo-module#from_repository_to_modules Updates #34383 Updates #34094 Change-Id: If37dc422e973eba13f3a3aeb68bc7b96e2d7f73d Reviewed-on: https://go-review.googlesource.com/c/go/+/197059 Run-TryBot: Bryan C. Mills TryBot-Result: Gobot Gobot Reviewed-by: Jay Conrod --- src/cmd/go/internal/modload/query.go | 12 +++++++++++- src/cmd/go/testdata/script/mod_get_major.txt | 18 ++++++++++++++++++ 2 files changed, 29 insertions(+), 1 deletion(-) create mode 100644 src/cmd/go/testdata/script/mod_get_major.txt diff --git a/src/cmd/go/internal/modload/query.go b/src/cmd/go/internal/modload/query.go index 602bf47275..f3c003a7cd 100644 --- a/src/cmd/go/internal/modload/query.go +++ b/src/cmd/go/internal/modload/query.go @@ -471,7 +471,17 @@ func queryPrefixModules(candidateModules []string, queryModule func(path string) notExistErr = rErr } } else if err == nil { - err = r.err + if len(found) > 0 { + // golang.org/issue/34094: If we have already found a module + // containing the target package, ignore errors for modules with + // shorter paths. + + // golang.org/issue/34383 is a special case of this: if we have + // already found example.com/foo/v2@v2.0.0 with a matching go.mod + // file, ignore the error from example.com/foo@v2.0.0. + } else { + err = r.err + } } } } diff --git a/src/cmd/go/testdata/script/mod_get_major.txt b/src/cmd/go/testdata/script/mod_get_major.txt new file mode 100644 index 0000000000..dd1cbe01a3 --- /dev/null +++ b/src/cmd/go/testdata/script/mod_get_major.txt @@ -0,0 +1,18 @@ +[!net] skip +[!exec:git] skip + +env GO111MODULE=on +env GOPROXY=direct +env GOSUMDB=off + +# golang.org/issue/34383: if a module path ends in a major-version suffix, +# ensure that 'direct' mode can resolve the package to a module. + +go get -d vcs-test.golang.org/git/v3pkg.git/v3@v3.0.0 + +go list -m vcs-test.golang.org/git/v3pkg.git/v3 +stdout '^vcs-test.golang.org/git/v3pkg.git/v3 v3.0.0$' + +-- go.mod -- +module example.com +go 1.13