diff options
Diffstat (limited to 'vendor/golang.org/x/tools/imports/mod.go')
-rw-r--r-- | vendor/golang.org/x/tools/imports/mod.go | 355 |
1 files changed, 355 insertions, 0 deletions
diff --git a/vendor/golang.org/x/tools/imports/mod.go b/vendor/golang.org/x/tools/imports/mod.go new file mode 100644 index 00000000..018c43ce --- /dev/null +++ b/vendor/golang.org/x/tools/imports/mod.go @@ -0,0 +1,355 @@ +package imports + +import ( + "bytes" + "encoding/json" + "io/ioutil" + "log" + "os" + "path" + "path/filepath" + "regexp" + "sort" + "strconv" + "strings" + "sync" + "time" + + "golang.org/x/tools/internal/gopathwalk" + "golang.org/x/tools/internal/module" +) + +// moduleResolver implements resolver for modules using the go command as little +// as feasible. +type moduleResolver struct { + env *fixEnv + + initialized bool + main *moduleJSON + modsByModPath []*moduleJSON // All modules, ordered by # of path components in module Path... + modsByDir []*moduleJSON // ...or Dir. +} + +type moduleJSON struct { + Path string // module path + Version string // module version + Versions []string // available module versions (with -versions) + Replace *moduleJSON // replaced by this module + Time *time.Time // time version was created + Update *moduleJSON // available update, if any (with -u) + Main bool // is this the main module? + Indirect bool // is this module only an indirect dependency of main module? + Dir string // directory holding files for this module, if any + GoMod string // path to go.mod file for this module, if any + Error *moduleErrorJSON // error loading module +} + +type moduleErrorJSON struct { + Err string // the error itself +} + +func (r *moduleResolver) init() error { + if r.initialized { + return nil + } + stdout, err := r.env.invokeGo("list", "-m", "-json", "...") + if err != nil { + return err + } + for dec := json.NewDecoder(stdout); dec.More(); { + mod := &moduleJSON{} + if err := dec.Decode(mod); err != nil { + return err + } + if mod.Dir == "" { + if Debug { + log.Printf("module %v has not been downloaded and will be ignored", mod.Path) + } + // Can't do anything with a module that's not downloaded. + continue + } + r.modsByModPath = append(r.modsByModPath, mod) + r.modsByDir = append(r.modsByDir, mod) + if mod.Main { + r.main = mod + } + } + + sort.Slice(r.modsByModPath, func(i, j int) bool { + count := func(x int) int { + return strings.Count(r.modsByModPath[x].Path, "/") + } + return count(j) < count(i) // descending order + }) + sort.Slice(r.modsByDir, func(i, j int) bool { + count := func(x int) int { + return strings.Count(r.modsByDir[x].Dir, "/") + } + return count(j) < count(i) // descending order + }) + + r.initialized = true + return nil +} + +// findPackage returns the module and directory that contains the package at +// the given import path, or returns nil, "" if no module is in scope. +func (r *moduleResolver) findPackage(importPath string) (*moduleJSON, string) { + for _, m := range r.modsByModPath { + if !strings.HasPrefix(importPath, m.Path) { + continue + } + pathInModule := importPath[len(m.Path):] + pkgDir := filepath.Join(m.Dir, pathInModule) + if dirIsNestedModule(pkgDir, m) { + continue + } + + pkgFiles, err := ioutil.ReadDir(pkgDir) + if err != nil { + continue + } + + // A module only contains a package if it has buildable go + // files in that directory. If not, it could be provided by an + // outer module. See #29736. + for _, fi := range pkgFiles { + if ok, _ := r.env.buildContext().MatchFile(pkgDir, fi.Name()); ok { + return m, pkgDir + } + } + } + return nil, "" +} + +// findModuleByDir returns the module that contains dir, or nil if no such +// module is in scope. +func (r *moduleResolver) findModuleByDir(dir string) *moduleJSON { + // This is quite tricky and may not be correct. dir could be: + // - a package in the main module. + // - a replace target underneath the main module's directory. + // - a nested module in the above. + // - a replace target somewhere totally random. + // - a nested module in the above. + // - in the mod cache. + // - in /vendor/ in -mod=vendor mode. + // - nested module? Dunno. + // Rumor has it that replace targets cannot contain other replace targets. + for _, m := range r.modsByDir { + if !strings.HasPrefix(dir, m.Dir) { + continue + } + + if dirIsNestedModule(dir, m) { + continue + } + + return m + } + return nil +} + +// dirIsNestedModule reports if dir is contained in a nested module underneath +// mod, not actually in mod. +func dirIsNestedModule(dir string, mod *moduleJSON) bool { + if !strings.HasPrefix(dir, mod.Dir) { + return false + } + mf := findModFile(dir) + if mf == "" { + return false + } + return filepath.Dir(mf) != mod.Dir +} + +func findModFile(dir string) string { + for { + f := filepath.Join(dir, "go.mod") + info, err := os.Stat(f) + if err == nil && !info.IsDir() { + return f + } + d := filepath.Dir(dir) + if len(d) >= len(dir) { + return "" // reached top of file system, no go.mod + } + dir = d + } +} + +func (r *moduleResolver) loadPackageNames(importPaths []string, srcDir string) (map[string]string, error) { + if err := r.init(); err != nil { + return nil, err + } + names := map[string]string{} + for _, path := range importPaths { + _, packageDir := r.findPackage(path) + if packageDir == "" { + continue + } + name, err := packageDirToName(packageDir) + if err != nil { + continue + } + names[path] = name + } + return names, nil +} + +func (r *moduleResolver) scan(_ references) ([]*pkg, error) { + if err := r.init(); err != nil { + return nil, err + } + + // Walk GOROOT, GOPATH/pkg/mod, and the main module. + roots := []gopathwalk.Root{ + {filepath.Join(r.env.GOROOT, "/src"), gopathwalk.RootGOROOT}, + } + if r.main != nil { + roots = append(roots, gopathwalk.Root{r.main.Dir, gopathwalk.RootCurrentModule}) + } + for _, p := range filepath.SplitList(r.env.GOPATH) { + roots = append(roots, gopathwalk.Root{filepath.Join(p, "/pkg/mod"), gopathwalk.RootModuleCache}) + } + + // Walk replace targets, just in case they're not in any of the above. + for _, mod := range r.modsByModPath { + if mod.Replace != nil { + roots = append(roots, gopathwalk.Root{mod.Dir, gopathwalk.RootOther}) + } + } + + var result []*pkg + dupCheck := make(map[string]bool) + var mu sync.Mutex + + gopathwalk.Walk(roots, func(root gopathwalk.Root, dir string) { + mu.Lock() + defer mu.Unlock() + + if _, dup := dupCheck[dir]; dup { + return + } + + dupCheck[dir] = true + + subdir := "" + if dir != root.Path { + subdir = dir[len(root.Path)+len("/"):] + } + importPath := filepath.ToSlash(subdir) + if strings.HasPrefix(importPath, "vendor/") { + // Ignore vendor dirs. If -mod=vendor is on, then things + // should mostly just work, but when it's not vendor/ + // is a mess. There's no easy way to tell if it's on. + // We can still find things in the mod cache and + // map them into /vendor when -mod=vendor is on. + return + } + switch root.Type { + case gopathwalk.RootCurrentModule: + importPath = path.Join(r.main.Path, filepath.ToSlash(subdir)) + case gopathwalk.RootModuleCache: + matches := modCacheRegexp.FindStringSubmatch(subdir) + modPath, err := module.DecodePath(filepath.ToSlash(matches[1])) + if err != nil { + if Debug { + log.Printf("decoding module cache path %q: %v", subdir, err) + } + return + } + importPath = path.Join(modPath, filepath.ToSlash(matches[3])) + case gopathwalk.RootGOROOT: + importPath = subdir + } + + // Check if the directory is underneath a module that's in scope. + if mod := r.findModuleByDir(dir); mod != nil { + // It is. If dir is the target of a replace directive, + // our guessed import path is wrong. Use the real one. + if mod.Dir == dir { + importPath = mod.Path + } else { + dirInMod := dir[len(mod.Dir)+len("/"):] + importPath = path.Join(mod.Path, filepath.ToSlash(dirInMod)) + } + } else { + // The package is in an unknown module. Check that it's + // not obviously impossible to import. + var modFile string + switch root.Type { + case gopathwalk.RootModuleCache: + matches := modCacheRegexp.FindStringSubmatch(subdir) + modFile = filepath.Join(matches[1], "@", matches[2], "go.mod") + default: + modFile = findModFile(dir) + } + + modBytes, err := ioutil.ReadFile(modFile) + if err == nil && !strings.HasPrefix(importPath, modulePath(modBytes)) { + // The module's declared path does not match + // its expected path. It probably needs a + // replace directive we don't have. + return + } + } + // We may have discovered a package that has a different version + // in scope already. Canonicalize to that one if possible. + if _, canonicalDir := r.findPackage(importPath); canonicalDir != "" { + dir = canonicalDir + } + + result = append(result, &pkg{ + importPathShort: VendorlessPath(importPath), + dir: dir, + }) + }, gopathwalk.Options{Debug: Debug, ModulesEnabled: true}) + return result, nil +} + +// modCacheRegexp splits a path in a module cache into module, module version, and package. +var modCacheRegexp = regexp.MustCompile(`(.*)@([^/\\]*)(.*)`) + +var ( + slashSlash = []byte("//") + moduleStr = []byte("module") +) + +// modulePath returns the module path from the gomod file text. +// If it cannot find a module path, it returns an empty string. +// It is tolerant of unrelated problems in the go.mod file. +// +// Copied from cmd/go/internal/modfile. +func modulePath(mod []byte) string { + for len(mod) > 0 { + line := mod + mod = nil + if i := bytes.IndexByte(line, '\n'); i >= 0 { + line, mod = line[:i], line[i+1:] + } + if i := bytes.Index(line, slashSlash); i >= 0 { + line = line[:i] + } + line = bytes.TrimSpace(line) + if !bytes.HasPrefix(line, moduleStr) { + continue + } + line = line[len(moduleStr):] + n := len(line) + line = bytes.TrimSpace(line) + if len(line) == n || len(line) == 0 { + continue + } + + if line[0] == '"' || line[0] == '`' { + p, err := strconv.Unquote(string(line)) + if err != nil { + return "" // malformed quoted string or multiline module path + } + return p + } + + return string(line) + } + return "" // missing module path +} |