From c9211577eb77df9c51f0565f1da7d20ff91d59df Mon Sep 17 00:00:00 2001 From: "Bryan C. Mills" Date: Fri, 2 Oct 2020 16:25:17 -0400 Subject: cmd/go/internal/modfetch: remove error return from Lookup MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit We generally don't care about errors in resolving a repo if the result we're looking for is already in the module cache. Moreover, we can avoid some expense in initializing the repo if all of the methods we plan to call on it hit in the cache — especially when using GOPROXY=direct. This also incidentally fixes a possible (but rare) bug in Download: we had forgotten to reset the downloaded file in case the Zip method returned an error after writing a nonzero number of bytes. For #37438 Change-Id: Ib64f10f763f6d1936536b8e1f7d31ed1b463e955 Reviewed-on: https://go-review.googlesource.com/c/go/+/259158 Trust: Bryan C. Mills Trust: Jay Conrod Run-TryBot: Bryan C. Mills TryBot-Result: Go Bot Reviewed-by: Michael Matloob Reviewed-by: Jay Conrod --- src/cmd/go/internal/modfetch/repo.go | 38 +++++++++++++++++++++++++----------- 1 file changed, 27 insertions(+), 11 deletions(-) (limited to 'src/cmd/go/internal/modfetch/repo.go') diff --git a/src/cmd/go/internal/modfetch/repo.go b/src/cmd/go/internal/modfetch/repo.go index eed4dd4258..4936ec11aa 100644 --- a/src/cmd/go/internal/modfetch/repo.go +++ b/src/cmd/go/internal/modfetch/repo.go @@ -188,27 +188,26 @@ type lookupCacheKey struct { // // A successful return does not guarantee that the module // has any defined versions. -func Lookup(proxy, path string) (Repo, error) { +func Lookup(proxy, path string) Repo { if traceRepo { defer logCall("Lookup(%q, %q)", proxy, path)() } type cached struct { - r Repo - err error + r Repo } c := lookupCache.Do(lookupCacheKey{proxy, path}, func() interface{} { - r, err := lookup(proxy, path) - if err == nil { - if traceRepo { + r := newCachingRepo(path, func() (Repo, error) { + r, err := lookup(proxy, path) + if err == nil && traceRepo { r = newLoggingRepo(r) } - r = newCachingRepo(r) - } - return cached{r, err} + return r, err + }) + return cached{r} }).(cached) - return c.r, c.err + return c.r } // lookup returns the module with the given module path. @@ -228,7 +227,7 @@ func lookup(proxy, path string) (r Repo, err error) { switch proxy { case "off": - return nil, errProxyOff + return errRepo{path, errProxyOff}, nil case "direct": return lookupDirect(path) case "noproxy": @@ -407,6 +406,23 @@ func (l *loggingRepo) Zip(dst io.Writer, version string) error { return l.r.Zip(dst, version) } +// errRepo is a Repo that returns the same error for all operations. +// +// It is useful in conjunction with caching, since cache hits will not attempt +// the prohibited operations. +type errRepo struct { + modulePath string + err error +} + +func (r errRepo) ModulePath() string { return r.modulePath } + +func (r errRepo) Versions(prefix string) (tags []string, err error) { return nil, r.err } +func (r errRepo) Stat(rev string) (*RevInfo, error) { return nil, r.err } +func (r errRepo) Latest() (*RevInfo, error) { return nil, r.err } +func (r errRepo) GoMod(version string) ([]byte, error) { return nil, r.err } +func (r errRepo) Zip(dst io.Writer, version string) error { return r.err } + // A notExistError is like os.ErrNotExist, but with a custom message type notExistError struct { err error -- cgit v1.2.1 From ff052737a946b5f9381dc054d61857ee4d500899 Mon Sep 17 00:00:00 2001 From: "Bryan C. Mills" Date: Mon, 28 Sep 2020 20:59:47 -0400 Subject: cmd/go/internal/modload: allow 'go get' to use replaced versions 'go mod tidy' has been able to use replaced versions since CL 152739, but 'go get' failed for many of the same paths. Now that we are recommending 'go get' more aggressively due to #40728, we should make that work too. In the future, we might consider factoring out the new replacementRepo type so that 'go list' can report the new versions as well. For #41577 For #41416 For #37438 Updates #26241 Change-Id: I9140c556424b584fdd9bdd0a747842774664a7d8 Reviewed-on: https://go-review.googlesource.com/c/go/+/258220 Trust: Bryan C. Mills Trust: Jay Conrod Run-TryBot: Bryan C. Mills TryBot-Result: Go Bot Reviewed-by: Michael Matloob Reviewed-by: Jay Conrod --- src/cmd/go/internal/modfetch/repo.go | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'src/cmd/go/internal/modfetch/repo.go') diff --git a/src/cmd/go/internal/modfetch/repo.go b/src/cmd/go/internal/modfetch/repo.go index 4936ec11aa..c7cf5595bd 100644 --- a/src/cmd/go/internal/modfetch/repo.go +++ b/src/cmd/go/internal/modfetch/repo.go @@ -32,8 +32,17 @@ type Repo interface { // Versions lists all known versions with the given prefix. // Pseudo-versions are not included. + // // Versions should be returned sorted in semver order // (implementations can use SortVersions). + // + // Versions returns a non-nil error only if there was a problem + // fetching the list of versions: it may return an empty list + // along with a nil error if the list of matching versions + // is known to be empty. + // + // If the underlying repository does not exist, + // Versions returns an error matching errors.Is(_, os.NotExist). Versions(prefix string) ([]string, error) // Stat returns information about the revision rev. -- cgit v1.2.1 From 7bb721b9384bdd196befeaed593b185f7f2a5589 Mon Sep 17 00:00:00 2001 From: Russ Cox Date: Tue, 7 Jul 2020 13:49:21 -0400 Subject: all: update references to symbols moved from os to io/fs The old os references are still valid, but update our code to reflect best practices and get used to the new locations. Code compiled with the bootstrap toolchain (cmd/asm, cmd/dist, cmd/compile, debug/elf) must remain Go 1.4-compatible and is excluded. For #41190. Change-Id: I8f9526977867c10a221e2f392f78d7dec073f1bd Reviewed-on: https://go-review.googlesource.com/c/go/+/243907 Trust: Russ Cox Run-TryBot: Russ Cox TryBot-Result: Go Bot Reviewed-by: Rob Pike --- src/cmd/go/internal/modfetch/repo.go | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'src/cmd/go/internal/modfetch/repo.go') diff --git a/src/cmd/go/internal/modfetch/repo.go b/src/cmd/go/internal/modfetch/repo.go index c7cf5595bd..af9e24cefd 100644 --- a/src/cmd/go/internal/modfetch/repo.go +++ b/src/cmd/go/internal/modfetch/repo.go @@ -7,6 +7,7 @@ package modfetch import ( "fmt" "io" + "io/fs" "os" "sort" "strconv" @@ -432,7 +433,7 @@ func (r errRepo) Latest() (*RevInfo, error) { return nil func (r errRepo) GoMod(version string) ([]byte, error) { return nil, r.err } func (r errRepo) Zip(dst io.Writer, version string) error { return r.err } -// A notExistError is like os.ErrNotExist, but with a custom message +// A notExistError is like fs.ErrNotExist, but with a custom message type notExistError struct { err error } @@ -446,7 +447,7 @@ func (e notExistError) Error() string { } func (notExistError) Is(target error) bool { - return target == os.ErrNotExist + return target == fs.ErrNotExist } func (e notExistError) Unwrap() error { -- cgit v1.2.1