diff --git a/src/cmd/go/internal/modload/init.go b/src/cmd/go/internal/modload/init.go index f5aac4b2206ff..8fe71a2448729 100644 --- a/src/cmd/go/internal/modload/init.go +++ b/src/cmd/go/internal/modload/init.go @@ -18,6 +18,7 @@ import ( "path/filepath" "strconv" "strings" + "sync" "cmd/go/internal/base" "cmd/go/internal/cfg" @@ -911,7 +912,10 @@ func WriteGoMod() { // The go.mod file has the same semantic content that it had before // (but not necessarily the same exact bytes). // Don't write go.mod, but write go.sum in case we added or trimmed sums. - modfetch.WriteGoSum(keepSums(true)) + // 'go mod init' shouldn't write go.sum, since it will be incomplete. + if cfg.CmdName != "mod init" { + modfetch.WriteGoSum(keepSums(true)) + } return } @@ -924,7 +928,10 @@ func WriteGoMod() { index = indexModFile(new, modFile, false) // Update go.sum after releasing the side lock and refreshing the index. - modfetch.WriteGoSum(keepSums(true)) + // 'go mod init' shouldn't write go.sum, since it will be incomplete. + if cfg.CmdName != "mod init" { + modfetch.WriteGoSum(keepSums(true)) + } }() // Make a best-effort attempt to acquire the side lock, only to exclude @@ -969,41 +976,55 @@ func WriteGoMod() { // If addDirect is true, the set also includes sums for modules directly // required by go.mod, as represented by the index, with replacements applied. func keepSums(addDirect bool) map[module.Version]bool { - // Walk the module graph and keep sums needed by MVS. + // Re-derive the build list using the current list of direct requirements. + // Keep the sum for the go.mod of each visited module version (or its + // replacement). modkey := func(m module.Version) module.Version { return module.Version{Path: m.Path, Version: m.Version + "/go.mod"} } keep := make(map[module.Version]bool) - replaced := make(map[module.Version]bool) - reqs := Reqs() - var walk func(module.Version) - walk = func(m module.Version) { - // If we build using a replacement module, keep the sum for the replacement, - // since that's the code we'll actually use during a build. - r := Replacement(m) - if r.Path == "" { - keep[modkey(m)] = true - } else { - replaced[m] = true - keep[modkey(r)] = true - } - list, _ := reqs.Required(m) - for _, r := range list { - if !keep[modkey(r)] && !replaced[r] { - walk(r) + var mu sync.Mutex + reqs := &keepSumReqs{ + Reqs: Reqs(), + visit: func(m module.Version) { + // If we build using a replacement module, keep the sum for the replacement, + // since that's the code we'll actually use during a build. + mu.Lock() + r := Replacement(m) + if r.Path == "" { + keep[modkey(m)] = true + } else { + keep[modkey(r)] = true } - } + mu.Unlock() + }, + } + buildList, err := mvs.BuildList(Target, reqs) + if err != nil { + panic(fmt.Sprintf("unexpected error reloading build list: %v", err)) } - walk(Target) - // Add entries for modules from which packages were loaded. + // Add entries for modules in the build list with paths that are prefixes of + // paths of loaded packages. We need to retain sums for modules needed to + // report ambiguous import errors. We use our re-derived build list, + // since the global build list may have been tidied. if loaded != nil { - for _, pkg := range loaded.pkgs { - m := pkg.mod + actualMods := make(map[string]module.Version) + for _, m := range buildList[1:] { if r := Replacement(m); r.Path != "" { - keep[r] = true + actualMods[m.Path] = r } else { - keep[m] = true + actualMods[m.Path] = m + } + } + for _, pkg := range loaded.pkgs { + if pkg.testOf != nil || pkg.inStd { + continue + } + for prefix := pkg.path; prefix != "."; prefix = path.Dir(prefix) { + if m, ok := actualMods[prefix]; ok { + keep[m] = true + } } } } @@ -1025,6 +1046,18 @@ func keepSums(addDirect bool) map[module.Version]bool { return keep } +// keepSumReqs embeds another Reqs implementation. The Required method +// calls visit for each version in the module graph. +type keepSumReqs struct { + mvs.Reqs + visit func(module.Version) +} + +func (r *keepSumReqs) Required(m module.Version) ([]module.Version, error) { + r.visit(m) + return r.Reqs.Required(m) +} + func TrimGoSum() { // Don't retain sums for direct requirements in go.mod. When TrimGoSum is // called, go.mod has not been updated, and it may contain requirements on diff --git a/src/cmd/go/testdata/mod/example.com_ambiguous_a_b_v0.0.0-empty.txt b/src/cmd/go/testdata/mod/example.com_ambiguous_a_b_v0.0.0-empty.txt new file mode 100644 index 0000000000000..a86951981e259 --- /dev/null +++ b/src/cmd/go/testdata/mod/example.com_ambiguous_a_b_v0.0.0-empty.txt @@ -0,0 +1,12 @@ +Module example.com/ambiguous/a/b is a suffix of example.com/a. +This version contains no package. +-- .mod -- +module example.com/ambiguous/a/b + +go 1.16 +-- .info -- +{"Version":"v0.0.0-empty"} +-- go.mod -- +module example.com/ambiguous/a/b + +go 1.16 diff --git a/src/cmd/go/testdata/mod/example.com_ambiguous_a_v1.0.0.txt b/src/cmd/go/testdata/mod/example.com_ambiguous_a_v1.0.0.txt new file mode 100644 index 0000000000000..bb438262e134b --- /dev/null +++ b/src/cmd/go/testdata/mod/example.com_ambiguous_a_v1.0.0.txt @@ -0,0 +1,18 @@ +Module example.com/ambiguous/a is a prefix of example.com/a/b. +It contains package example.com/a/b. +-- .mod -- +module example.com/ambiguous/a + +go 1.16 + +require example.com/ambiguous/a/b v0.0.0-empty +-- .info -- +{"Version":"v1.0.0"} +-- go.mod -- +module example.com/ambiguous/a + +go 1.16 + +require example.com/ambiguous/a/b v0.0.0-empty +-- b/b.go -- +package b diff --git a/src/cmd/go/testdata/script/mod_sum_ambiguous.txt b/src/cmd/go/testdata/script/mod_sum_ambiguous.txt new file mode 100644 index 0000000000000..999257c419f8e --- /dev/null +++ b/src/cmd/go/testdata/script/mod_sum_ambiguous.txt @@ -0,0 +1,48 @@ +# Confirm our build list. +cp go.sum.buildlist-only go.sum +go list -m all +stdout '^example.com/ambiguous/a v1.0.0$' +stdout '^example.com/ambiguous/a/b v0.0.0-empty$' + +# If two modules could provide a package, but only one does, +# 'go mod tidy' should retain sums for both zips. +go mod tidy +grep '^example.com/ambiguous/a v1.0.0 h1:' go.sum +grep '^example.com/ambiguous/a/b v0.0.0-empty h1:' go.sum + +# If two modules could provide a package, and we're missing a sum for one, +# we should see a missing sum error, even if we have a sum for a module that +# provides the package. +cp go.sum.a-only go.sum +! go list example.com/ambiguous/a/b +stderr '^missing go.sum entry needed to verify package example.com/ambiguous/a/b is provided by exactly one module$' +! go list -deps . +stderr '^use.go:3:8: missing go.sum entry needed to verify package example.com/ambiguous/a/b is provided by exactly one module; try ''go mod tidy'' to add it$' + +cp go.sum.b-only go.sum +! go list example.com/ambiguous/a/b +stderr '^missing go.sum entry for module providing package example.com/ambiguous/a/b$' +! go list -deps . +stderr '^use.go:3:8: missing go.sum entry for module providing package example.com/ambiguous/a/b; try ''go mod tidy'' to add it$' + +-- go.mod -- +module m + +go 1.15 + +require example.com/ambiguous/a v1.0.0 +-- go.sum.buildlist-only -- +example.com/ambiguous/a v1.0.0/go.mod h1:TrBl/3xTPFJ2gmMIYz53h2gkNtg0dokszEMuyS1QEb0= +example.com/ambiguous/a/b v0.0.0-empty/go.mod h1:MajJq5jPEBnnXP+NTWIeXX7kwaPS1sbVEJdooTmsePQ= +-- go.sum.a-only -- +example.com/ambiguous/a v1.0.0 h1:pGZhTXy6+titE2rNfwHwJykSjXDR4plO52PfZrBM0T8= +example.com/ambiguous/a v1.0.0/go.mod h1:TrBl/3xTPFJ2gmMIYz53h2gkNtg0dokszEMuyS1QEb0= +example.com/ambiguous/a/b v0.0.0-empty/go.mod h1:MajJq5jPEBnnXP+NTWIeXX7kwaPS1sbVEJdooTmsePQ= +-- go.sum.b-only -- +example.com/ambiguous/a v1.0.0/go.mod h1:TrBl/3xTPFJ2gmMIYz53h2gkNtg0dokszEMuyS1QEb0= +example.com/ambiguous/a/b v0.0.0-empty h1:xS29ReXXuhjT7jc79mo91h/PevaZ2oS9PciF1DucXtg= +example.com/ambiguous/a/b v0.0.0-empty/go.mod h1:MajJq5jPEBnnXP+NTWIeXX7kwaPS1sbVEJdooTmsePQ= +-- use.go -- +package use + +import _ "example.com/ambiguous/a/b"