diff options
Diffstat (limited to 'src/cmd/go/internal/modload/import.go')
| -rw-r--r-- | src/cmd/go/internal/modload/import.go | 379 |
1 files changed, 247 insertions, 132 deletions
diff --git a/src/cmd/go/internal/modload/import.go b/src/cmd/go/internal/modload/import.go index 6459e716b7..ce5671728e 100644 --- a/src/cmd/go/internal/modload/import.go +++ b/src/cmd/go/internal/modload/import.go @@ -10,14 +10,14 @@ import ( "fmt" "go/build" "internal/goroot" + "io/fs" "os" "path/filepath" "sort" "strings" - "time" "cmd/go/internal/cfg" - "cmd/go/internal/load" + "cmd/go/internal/fsys" "cmd/go/internal/modfetch" "cmd/go/internal/par" "cmd/go/internal/search" @@ -31,23 +31,60 @@ type ImportMissingError struct { Module module.Version QueryErr error + // inAll indicates whether Path is in the "all" package pattern, + // and thus would be added by 'go mod tidy'. + inAll bool + + // isStd indicates whether we would expect to find the package in the standard + // library. This is normally true for all dotless import paths, but replace + // directives can cause us to treat the replaced paths as also being in + // modules. + isStd bool + + // replaced the highest replaced version of the module where the replacement + // contains the package. replaced is only set if the replacement is unused. + replaced module.Version + // newMissingVersion is set to a newer version of Module if one is present // in the build list. When set, we can't automatically upgrade. newMissingVersion string } -var _ load.ImportPathError = (*ImportMissingError)(nil) - func (e *ImportMissingError) Error() string { if e.Module.Path == "" { - if search.IsStandardImportPath(e.Path) { + if e.isStd { return fmt.Sprintf("package %s is not in GOROOT (%s)", e.Path, filepath.Join(cfg.GOROOT, "src", e.Path)) } if e.QueryErr != nil { return fmt.Sprintf("cannot find module providing package %s: %v", e.Path, e.QueryErr) } - return "cannot find module providing package " + e.Path + if cfg.BuildMod == "mod" { + return "cannot find module providing package " + e.Path + } + + if e.replaced.Path != "" { + suggestArg := e.replaced.Path + if !modfetch.IsZeroPseudoVersion(e.replaced.Version) { + suggestArg = e.replaced.String() + } + return fmt.Sprintf("module %s provides package %s and is replaced but not required; try 'go get -d %s' to add it", e.replaced.Path, e.Path, suggestArg) + } + + suggestion := "" + if !HasModRoot() { + suggestion = ": working directory is not part of a module" + } else if e.inAll { + suggestion = "; try 'go mod tidy' to add it" + } else { + suggestion = fmt.Sprintf("; try 'go get -d %s' to add it", e.Path) + } + return fmt.Sprintf("no required module provides package %s%s", e.Path, suggestion) } + + if e.newMissingVersion != "" { + return fmt.Sprintf("package %s provided by %s at latest version %s but not at required version %s", e.Path, e.Module.Path, e.Module.Version, e.newMissingVersion) + } + return fmt.Sprintf("missing module for import: %s@%s provides %s", e.Module.Path, e.Module.Version, e.Path) } @@ -98,20 +135,62 @@ func (e *AmbiguousImportError) Error() string { return buf.String() } -var _ load.ImportPathError = &AmbiguousImportError{} +// ImportMissingSumError is reported in readonly mode when we need to check +// if a module in the build list contains a package, but we don't have a sum +// for its .zip file. +type ImportMissingSumError struct { + importPath string + found, inAll bool +} -// Import finds the module and directory in the build list -// containing the package with the given import path. -// The answer must be unique: Import returns an error -// if multiple modules attempt to provide the same package. -// Import can return a module with an empty m.Path, for packages in the standard library. -// Import can return an empty directory string, for fake packages like "C" and "unsafe". +func (e *ImportMissingSumError) Error() string { + var message string + if e.found { + message = fmt.Sprintf("missing go.sum entry needed to verify package %s is provided by exactly one module", e.importPath) + } else { + message = fmt.Sprintf("missing go.sum entry for module providing package %s", e.importPath) + } + if e.inAll { + return message + "; try 'go mod tidy' to add it" + } + return message +} + +func (e *ImportMissingSumError) ImportPath() string { + return e.importPath +} + +type invalidImportError struct { + importPath string + err error +} + +func (e *invalidImportError) ImportPath() string { + return e.importPath +} + +func (e *invalidImportError) Error() string { + return e.err.Error() +} + +func (e *invalidImportError) Unwrap() error { + return e.err +} + +// importFromBuildList finds the module and directory in the build list +// containing the package with the given import path. The answer must be unique: +// importFromBuildList returns an error if multiple modules attempt to provide +// the same package. // -// If the package cannot be found in the current build list, -// Import returns an ImportMissingError as the error. -// If Import can identify a module that could be added to supply the package, -// the ImportMissingError records that module. -func Import(ctx context.Context, path string) (m module.Version, dir string, err error) { +// importFromBuildList can return a module with an empty m.Path, for packages in +// the standard library. +// +// importFromBuildList can return an empty directory string, for fake packages +// like "C" and "unsafe". +// +// If the package cannot be found in buildList, +// importFromBuildList returns an *ImportMissingError. +func importFromBuildList(ctx context.Context, path string, buildList []module.Version) (m module.Version, dir string, err error) { if strings.Contains(path, "@") { return module.Version{}, "", fmt.Errorf("import path should not have @version") } @@ -122,6 +201,10 @@ func Import(ctx context.Context, path string) (m module.Version, dir string, err // There's no directory for import "C" or import "unsafe". return module.Version{}, "", nil } + // Before any further lookup, check that the path is valid. + if err := module.CheckImportPath(path); err != nil { + return module.Version{}, "", &invalidImportError{importPath: path, err: err} + } // Is the package in the standard library? pathIsStd := search.IsStandardImportPath(path) @@ -161,13 +244,23 @@ func Import(ctx context.Context, path string) (m module.Version, dir string, err // Check each module on the build list. var dirs []string var mods []module.Version + haveSumErr := false for _, m := range buildList { if !maybeInModule(path, m.Path) { // Avoid possibly downloading irrelevant modules. continue } - root, isLocal, err := fetch(ctx, m) + needSum := true + root, isLocal, err := fetch(ctx, m, needSum) if err != nil { + if sumErr := (*sumMissingError)(nil); errors.As(err, &sumErr) { + // We are missing a sum needed to fetch a module in the build list. + // We can't verify that the package is unique, and we may not find + // the package at all. Keep checking other modules to decide which + // error to report. + haveSumErr = true + continue + } // Report fetch error. // Note that we don't know for sure this module is necessary, // but it certainly _could_ provide the package, and even if we @@ -183,88 +276,76 @@ func Import(ctx context.Context, path string) (m module.Version, dir string, err dirs = append(dirs, dir) } } - if len(mods) == 1 { - return mods[0], dirs[0], nil - } - if len(mods) > 0 { + if len(mods) > 1 { return module.Version{}, "", &AmbiguousImportError{importPath: path, Dirs: dirs, Modules: mods} } - - // Look up module containing the package, for addition to the build list. - // Goal is to determine the module, download it to dir, and return m, dir, ErrMissing. - if cfg.BuildMod == "readonly" { - var queryErr error - if !pathIsStd { - if cfg.BuildModReason == "" { - queryErr = fmt.Errorf("import lookup disabled by -mod=%s", cfg.BuildMod) - } else { - queryErr = fmt.Errorf("import lookup disabled by -mod=%s\n\t(%s)", cfg.BuildMod, cfg.BuildModReason) - } - } - return module.Version{}, "", &ImportMissingError{Path: path, QueryErr: queryErr} + if haveSumErr { + return module.Version{}, "", &ImportMissingSumError{importPath: path, found: len(mods) > 0} } - if modRoot == "" && !allowMissingModuleImports { - return module.Version{}, "", &ImportMissingError{ - Path: path, - QueryErr: errors.New("working directory is not part of a module"), - } + if len(mods) == 1 { + return mods[0], dirs[0], nil } - // Not on build list. - // To avoid spurious remote fetches, next try the latest replacement for each module. - // (golang.org/issue/26241) - if modFile != nil { - latest := map[string]string{} // path -> version - for _, r := range modFile.Replace { - if maybeInModule(path, r.Old.Path) { - // Don't use semver.Max here; need to preserve +incompatible suffix. - v := latest[r.Old.Path] - if semver.Compare(r.Old.Version, v) > 0 { - v = r.Old.Version - } - latest[r.Old.Path] = v - } - } + return module.Version{}, "", &ImportMissingError{Path: path, isStd: pathIsStd} +} - mods = make([]module.Version, 0, len(latest)) - for p, v := range latest { - // If the replacement didn't specify a version, synthesize a - // pseudo-version with an appropriate major version and a timestamp below - // any real timestamp. That way, if the main module is used from within - // some other module, the user will be able to upgrade the requirement to - // any real version they choose. - if v == "" { - if _, pathMajor, ok := module.SplitPathVersion(p); ok && len(pathMajor) > 0 { - v = modfetch.PseudoVersion(pathMajor[1:], "", time.Time{}, "000000000000") +// queryImport attempts to locate a module that can be added to the current +// build list to provide the package with the given import path. +// +// Unlike QueryPattern, queryImport prefers to add a replaced version of a +// module *before* checking the proxies for a version to add. +func queryImport(ctx context.Context, path string) (module.Version, error) { + // To avoid spurious remote fetches, try the latest replacement for each + // module (golang.org/issue/26241). + if index != nil { + var mods []module.Version + for mp, mv := range index.highestReplaced { + if !maybeInModule(path, mp) { + continue + } + if mv == "" { + // The only replacement is a wildcard that doesn't specify a version, so + // synthesize a pseudo-version with an appropriate major version and a + // timestamp below any real timestamp. That way, if the main module is + // used from within some other module, the user will be able to upgrade + // the requirement to any real version they choose. + if _, pathMajor, ok := module.SplitPathVersion(mp); ok && len(pathMajor) > 0 { + mv = modfetch.ZeroPseudoVersion(pathMajor[1:]) } else { - v = modfetch.PseudoVersion("v0", "", time.Time{}, "000000000000") + mv = modfetch.ZeroPseudoVersion("v0") } } - mods = append(mods, module.Version{Path: p, Version: v}) + mods = append(mods, module.Version{Path: mp, Version: mv}) } // Every module path in mods is a prefix of the import path. - // As in QueryPackage, prefer the longest prefix that satisfies the import. + // As in QueryPattern, prefer the longest prefix that satisfies the import. sort.Slice(mods, func(i, j int) bool { return len(mods[i].Path) > len(mods[j].Path) }) for _, m := range mods { - root, isLocal, err := fetch(ctx, m) + needSum := true + root, isLocal, err := fetch(ctx, m, needSum) if err != nil { - // Report fetch error as above. - return module.Version{}, "", err + if sumErr := (*sumMissingError)(nil); errors.As(err, &sumErr) { + return module.Version{}, &ImportMissingSumError{importPath: path} + } + return module.Version{}, err } if _, ok, err := dirInModule(path, m.Path, root, isLocal); err != nil { - return m, "", err + return m, err } else if ok { - return m, "", &ImportMissingError{Path: path, Module: m} + if cfg.BuildMod == "readonly" { + return module.Version{}, &ImportMissingError{Path: path, replaced: m} + } + return m, nil } } if len(mods) > 0 && module.CheckPath(path) != nil { // The package path is not valid to fetch remotely, - // so it can only exist if in a replaced module, + // so it can only exist in a replaced module, // and we know from the above loop that it is not. - return module.Version{}, "", &PackageNotInModuleError{ + return module.Version{}, &PackageNotInModuleError{ Mod: mods[0], Query: "latest", Pattern: path, @@ -273,36 +354,53 @@ func Import(ctx context.Context, path string) (m module.Version, dir string, err } } - if pathIsStd { + if search.IsStandardImportPath(path) { // This package isn't in the standard library, isn't in any module already // in the build list, and isn't in any other module that the user has // shimmed in via a "replace" directive. // Moreover, the import path is reserved for the standard library, so - // QueryPackage cannot possibly find a module containing this package. + // QueryPattern cannot possibly find a module containing this package. // - // Instead of trying QueryPackage, report an ImportMissingError immediately. - return module.Version{}, "", &ImportMissingError{Path: path} + // Instead of trying QueryPattern, report an ImportMissingError immediately. + return module.Version{}, &ImportMissingError{Path: path, isStd: true} + } + + if cfg.BuildMod == "readonly" { + // In readonly mode, we can't write go.mod, so we shouldn't try to look up + // the module. If readonly mode was enabled explicitly, include that in + // the error message. + var queryErr error + if cfg.BuildModExplicit { + queryErr = fmt.Errorf("import lookup disabled by -mod=%s", cfg.BuildMod) + } else if cfg.BuildModReason != "" { + queryErr = fmt.Errorf("import lookup disabled by -mod=%s\n\t(%s)", cfg.BuildMod, cfg.BuildModReason) + } + return module.Version{}, &ImportMissingError{Path: path, QueryErr: queryErr} } + // Look up module containing the package, for addition to the build list. + // Goal is to determine the module, download it to dir, + // and return m, dir, ImpportMissingError. fmt.Fprintf(os.Stderr, "go: finding module for package %s\n", path) - candidates, err := QueryPackage(ctx, path, "latest", CheckAllowed) + candidates, err := QueryPackages(ctx, path, "latest", Selected, CheckAllowed) if err != nil { - if errors.Is(err, os.ErrNotExist) { + if errors.Is(err, fs.ErrNotExist) { // Return "cannot find module providing package […]" instead of whatever - // low-level error QueryPackage produced. - return module.Version{}, "", &ImportMissingError{Path: path, QueryErr: err} + // low-level error QueryPattern produced. + return module.Version{}, &ImportMissingError{Path: path, QueryErr: err} } else { - return module.Version{}, "", err + return module.Version{}, err } } - m = candidates[0].Mod - newMissingVersion := "" - for _, c := range candidates { + + candidate0MissingVersion := "" + for i, c := range candidates { cm := c.Mod + canAdd := true for _, bm := range buildList { if bm.Path == cm.Path && semver.Compare(bm.Version, cm.Version) > 0 { - // QueryPackage proposed that we add module cm to provide the package, + // QueryPattern proposed that we add module cm to provide the package, // but we already depend on a newer version of that module (and we don't // have the package). // @@ -310,13 +408,22 @@ func Import(ctx context.Context, path string) (m module.Version, dir string, err // version (e.g., v1.0.0) of a module, but we have a newer version // of the same module in the build list (e.g., v1.0.1-beta), and // the package is not present there. - m = cm - newMissingVersion = bm.Version + canAdd = false + if i == 0 { + candidate0MissingVersion = bm.Version + } break } } + if canAdd { + return cm, nil + } + } + return module.Version{}, &ImportMissingError{ + Path: path, + Module: candidates[0].Mod, + newMissingVersion: candidate0MissingVersion, } - return m, "", &ImportMissingError{Path: path, Module: m, newMissingVersion: newMissingVersion} } // maybeInModule reports whether, syntactically, @@ -370,7 +477,7 @@ func dirInModule(path, mpath, mdir string, isLocal bool) (dir string, haveGoFile if isLocal { for d := dir; d != mdir && len(d) > len(mdir); { haveGoMod := haveGoModCache.Do(d, func() interface{} { - fi, err := os.Stat(filepath.Join(d, "go.mod")) + fi, err := fsys.Stat(filepath.Join(d, "go.mod")) return err == nil && !fi.IsDir() }).(bool) @@ -393,57 +500,65 @@ func dirInModule(path, mpath, mdir string, isLocal bool) (dir string, haveGoFile // We don't care about build tags, not even "+build ignore". // We're just looking for a plausible directory. res := haveGoFilesCache.Do(dir, func() interface{} { - ok, err := isDirWithGoFiles(dir) + ok, err := fsys.IsDirWithGoFiles(dir) return goFilesEntry{haveGoFiles: ok, err: err} }).(goFilesEntry) return dir, res.haveGoFiles, res.err } -func isDirWithGoFiles(dir string) (bool, error) { - f, err := os.Open(dir) - if err != nil { - if os.IsNotExist(err) { - return false, nil - } - return false, err - } - defer f.Close() - - names, firstErr := f.Readdirnames(-1) - if firstErr != nil { - if fi, err := f.Stat(); err == nil && !fi.IsDir() { - return false, nil - } - - // Rewrite the error from ReadDirNames to include the path if not present. - // See https://golang.org/issue/38923. - var pe *os.PathError - if !errors.As(firstErr, &pe) { - firstErr = &os.PathError{Op: "readdir", Path: dir, Err: firstErr} - } +// fetch downloads the given module (or its replacement) +// and returns its location. +// +// needSum indicates whether the module may be downloaded in readonly mode +// without a go.sum entry. It should only be false for modules fetched +// speculatively (for example, for incompatible version filtering). The sum +// will still be verified normally. +// +// The isLocal return value reports whether the replacement, +// if any, is local to the filesystem. +func fetch(ctx context.Context, mod module.Version, needSum bool) (dir string, isLocal bool, err error) { + if mod == Target { + return ModRoot(), true, nil } - - for _, name := range names { - if strings.HasSuffix(name, ".go") { - info, err := os.Stat(filepath.Join(dir, name)) - if err == nil && info.Mode().IsRegular() { - // If any .go source file exists, the package exists regardless of - // errors for other source files. Leave further error reporting for - // later. - return true, nil + if r := Replacement(mod); r.Path != "" { + if r.Version == "" { + dir = r.Path + if !filepath.IsAbs(dir) { + dir = filepath.Join(ModRoot(), dir) } - if firstErr == nil { + // Ensure that the replacement directory actually exists: + // dirInModule does not report errors for missing modules, + // so if we don't report the error now, later failures will be + // very mysterious. + if _, err := fsys.Stat(dir); err != nil { if os.IsNotExist(err) { - // If the file was concurrently deleted, or was a broken symlink, - // convert the error to an opaque error instead of one matching - // os.IsNotExist. - err = errors.New(err.Error()) + // Semantically the module version itself “exists” — we just don't + // have its source code. Remove the equivalence to os.ErrNotExist, + // and make the message more concise while we're at it. + err = fmt.Errorf("replacement directory %s does not exist", r.Path) + } else { + err = fmt.Errorf("replacement directory %s: %w", r.Path, err) } - firstErr = err + return dir, true, module.VersionError(mod, err) } + return dir, true, nil } + mod = r + } + + if cfg.BuildMod == "readonly" && needSum && !modfetch.HaveSum(mod) { + return "", false, module.VersionError(mod, &sumMissingError{}) } - return false, firstErr + dir, err = modfetch.Download(ctx, mod) + return dir, false, err +} + +type sumMissingError struct { + suggestion string +} + +func (e *sumMissingError) Error() string { + return "missing go.sum entry" + e.suggestion } |
