Golang Package.Path方法代码示例

//!+
func PrintSkeleton(pkg *types.Package, ifacename, concname string) error {
	obj := pkg.Scope().Lookup(ifacename)
	if obj == nil {
		return fmt.Errorf("%s.%s not found", pkg.Path(), ifacename)
	}
	if _, ok := obj.(*types.TypeName); !ok {
		return fmt.Errorf("%v is not a named type", obj)
	}
	iface, ok := obj.Type().Underlying().(*types.Interface)
	if !ok {
		return fmt.Errorf("type %v is a %T, not an interface",
			obj, obj.Type().Underlying())
	}
	// Use first letter of type name as receiver parameter.
	if !isValidIdentifier(concname) {
		return fmt.Errorf("invalid concrete type name: %q", concname)
	}
	r, _ := utf8.DecodeRuneInString(concname)

	fmt.Printf("// *%s implements %s.%s.\n", concname, pkg.Path(), ifacename)
	fmt.Printf("type %s struct{}\n", concname)
	mset := types.NewMethodSet(iface)
	for i := 0; i < mset.Len(); i++ {
		meth := mset.At(i).Obj()
		sig := types.TypeString(meth.Type(), (*types.Package).Name)
		fmt.Printf("func (%c *%s) %s%s {\n\tpanic(\"unimplemented\")\n}\n",
			r, concname, meth.Name(),
			strings.TrimPrefix(sig, "func"))
	}
	return nil
}

func (w *PkgWalker) LookupStructFromField(info *types.Info, cursorPkg *types.Package, cursorObj types.Object, cursorPos token.Pos) types.Object {
	if info == nil {
		conf := &PkgConfig{
			IgnoreFuncBodies: true,
			AllowBinary:      true,
			WithTestFiles:    true,
			Info: &types.Info{
				Defs: make(map[*ast.Ident]types.Object),
			},
		}
		w.imported[cursorPkg.Path()] = nil
		pkg, _ := w.Import("", cursorPkg.Path(), conf)
		if pkg != nil {
			info = conf.Info
		}
	}
	for _, obj := range info.Defs {
		if obj == nil {
			continue
		}
		if _, ok := obj.(*types.TypeName); ok {
			if t, ok := obj.Type().Underlying().(*types.Struct); ok {
				for i := 0; i < t.NumFields(); i++ {
					if t.Field(i).Pos() == cursorPos {
						return obj
					}
				}
			}
		}
	}
	return nil
}

func IsSamePkg(a, b *types.Package) bool {
	if a == b {
		return true
	}
	if a == nil || b == nil {
		return false
	}
	return a.Path() == b.Path()
}

func (w *PkgWalker) LookupImport(pkg *types.Package, pkgInfo *types.Info, cursor *FileCursor, is *ast.ImportSpec) {
	fpath, err := strconv.Unquote(is.Path.Value)
	if err != nil {
		return
	}

	if typesFindDef {
		fmt.Println(w.fset.Position(is.Pos()))
	}

	fbase := fpath
	pos := strings.LastIndexAny(fpath, "./-\\")
	if pos != -1 {
		fbase = fpath[pos+1:]
	}

	var fname string
	if is.Name != nil {
		fname = is.Name.Name
	} else {
		fname = fbase
	}

	if typesFindInfo {
		if fname == fpath {
			fmt.Printf("package %s\n", fname)
		} else {
			fmt.Printf("package %s (\"%s\")\n", fname, fpath)
		}
	}

	if !typesFindUse {
		return
	}

	path := pkg.Path()

	if strings.Contains(path, "vendor/") {
		path = strings.Split(path, "vendor/")[1]
	}

	fid := path + "." + fname

	var usages []int
	for id, obj := range pkgInfo.Uses {
		if obj != nil && obj.Id() == fid { //!= nil && cursorObj.Pos() == obj.Pos() {
			usages = append(usages, int(id.Pos()))
		}
	}

	(sort.IntSlice(usages)).Sort()
	for _, pos := range usages {
		fmt.Println(w.fset.Position(token.Pos(pos)))
	}
}

func (c *funcContext) pkgVar(pkg *types.Package) string {
	if pkg == c.p.Pkg {
		return "$pkg"
	}

	pkgVar, found := c.p.pkgVars[pkg.Path()]
	if !found {
		pkgVar = fmt.Sprintf(`$packages["%s"]`, pkg.Path())
	}
	return pkgVar
}

func (r *renamer) checkExport(id *ast.Ident, pkg *types.Package, from types.Object) bool {
	// Reject cross-package references if r.to is unexported.
	// (Such references may be qualified identifiers or field/method
	// selections.)
	if !ast.IsExported(r.to) && pkg != from.Pkg() {
		r.errorf(from.Pos(),
			"renaming this %s %q to %q would make it unexported",
			objectKind(from), from.Name(), r.to)
		r.errorf(id.Pos(), "\tbreaking references from packages such as %q",
			pkg.Path())
		return false
	}
	return true
}

// BuildPackage builds an SSA program with IR for a single package.
//
// It populates pkg by type-checking the specified file ASTs.  All
// dependencies are loaded using the importer specified by tc, which
// typically loads compiler export data; SSA code cannot be built for
// those packages.  BuildPackage then constructs an ssa.Program with all
// dependency packages created, and builds and returns the SSA package
// corresponding to pkg.
//
// The caller must have set pkg.Path() to the import path.
//
// The operation fails if there were any type-checking or import errors.
//
// See ../ssa/example_test.go for an example.
//
func BuildPackage(tc *types.Config, fset *token.FileSet, pkg *types.Package, files []*ast.File, mode ssa.BuilderMode) (*ssa.Package, *types.Info, error) {
	if fset == nil {
		panic("no token.FileSet")
	}
	if pkg.Path() == "" {
		panic("package has no import path")
	}

	info := &types.Info{
		Types:      make(map[ast.Expr]types.TypeAndValue),
		Defs:       make(map[*ast.Ident]types.Object),
		Uses:       make(map[*ast.Ident]types.Object),
		Implicits:  make(map[ast.Node]types.Object),
		Scopes:     make(map[ast.Node]*types.Scope),
		Selections: make(map[*ast.SelectorExpr]*types.Selection),
	}
	if err := types.NewChecker(tc, fset, pkg, info).Files(files); err != nil {
		return nil, nil, err
	}

	prog := ssa.NewProgram(fset, mode)

	// Create SSA packages for all imports.
	// Order is not significant.
	created := make(map[*types.Package]bool)
	var createAll func(pkgs []*types.Package)
	createAll = func(pkgs []*types.Package) {
		for _, p := range pkgs {
			if !created[p] {
				created[p] = true
				prog.CreatePackage(p, nil, nil, true)
				createAll(p.Imports())
			}
		}
	}
	createAll(pkg.Imports())

	// Create and build the primary package.
	ssapkg := prog.CreatePackage(pkg, files, info, false)
	ssapkg.Build()
	return ssapkg, info, nil
}

// NewPackageDef creates a new Def that represents a Go package.
func (g *Grapher) NewPackageDef(pkgInfo *loader.PackageInfo, pkg *types.Package) (*Def, error) {
	var pkgDir string
	if len(pkgInfo.Files) > 0 {
		pkgDir = filepath.Dir(g.program.Fset.Position(pkgInfo.Files[0].Package).Filename)
	}

	return &Def{
		Name: pkg.Name(),

		DefKey: &DefKey{PackageImportPath: pkg.Path(), Path: []string{}},

		File: pkgDir,

		DefInfo: definfo.DefInfo{
			Exported: true,
			PkgName:  pkg.Name(),
			Kind:     definfo.Package,
		},
	}, nil
}

func findFromObjects(iprog *loader.Program, spec *spec) ([]types.Object, error) {
	if spec.filename != "" {
		return findFromObjectsInFile(iprog, spec)
	}

	// Search for objects defined in specified package.

	// TODO(adonovan): the iprog.ImportMap has an entry {"main": ...}
	// for main packages, even though that's not an import path.
	// Seems like a bug.
	//
	// pkg := iprog.ImportMap[spec.pkg]
	// if pkg == nil {
	// 	return fmt.Errorf("cannot find package %s", spec.pkg) // can't happen?
	// }
	// info := iprog.AllPackages[pkg]

	// Workaround: lookup by value.
	var info *loader.PackageInfo
	var pkg *types.Package
	for pkg, info = range iprog.AllPackages {
		if pkg.Path() == spec.pkg {
			break
		}
	}
	if info == nil {
		return nil, fmt.Errorf("package %q was not loaded", spec.pkg)
	}

	objects, err := findObjects(info, spec)
	if err != nil {
		return nil, err
	}
	if len(objects) > 1 {
		// ambiguous "*" scope query
		return nil, ambiguityError(iprog.Fset, objects)
	}
	return objects, nil
}

func (p *exporter) pkg(pkg *types.Package) {
	if trace {
		p.tracef("package { ")
		defer p.tracef("} ")
	}

	if pkg == nil {
		panic("unexpected nil pkg")
	}

	// if the package was seen before, write its index (>= 0)
	if i, ok := p.pkgIndex[pkg]; ok {
		p.int(i)
		return
	}
	p.pkgIndex[pkg] = len(p.pkgIndex)

	// otherwise, write the package tag (< 0) and package data
	p.int(packageTag)
	p.string(pkg.Name())
	p.string(pkg.Path())
}

func describePackage(qpos *queryPos, path []ast.Node) (*describePackageResult, error) {
	var description string
	var pkg *types.Package
	switch n := path[0].(type) {
	case *ast.ImportSpec:
		var obj types.Object
		if n.Name != nil {
			obj = qpos.info.Defs[n.Name]
		} else {
			obj = qpos.info.Implicits[n]
		}
		pkgname, _ := obj.(*types.PkgName)
		if pkgname == nil {
			return nil, fmt.Errorf("can't import package %s", n.Path.Value)
		}
		pkg = pkgname.Imported()
		description = fmt.Sprintf("import of package %q", pkg.Path())

	case *ast.Ident:
		if _, isDef := path[1].(*ast.File); isDef {
			// e.g. package id
			pkg = qpos.info.Pkg
			description = fmt.Sprintf("definition of package %q", pkg.Path())
		} else {
			// e.g. import id "..."
			//  or  id.F()
			pkg = qpos.info.ObjectOf(n).(*types.PkgName).Imported()
			description = fmt.Sprintf("reference to package %q", pkg.Path())
		}

	default:
		// Unreachable?
		return nil, fmt.Errorf("unexpected AST for package: %T", n)
	}

	var members []*describeMember
	// NB: "unsafe" has no types.Package
	if pkg != nil {
		// Enumerate the accessible package members
		// in lexicographic order.
		for _, name := range pkg.Scope().Names() {
			if pkg == qpos.info.Pkg || ast.IsExported(name) {
				mem := pkg.Scope().Lookup(name)
				var methods []*types.Selection
				if mem, ok := mem.(*types.TypeName); ok {
					methods = accessibleMethods(mem.Type(), qpos.info.Pkg)
				}
				members = append(members, &describeMember{
					mem,
					methods,
				})

			}
		}
	}

	return &describePackageResult{qpos.fset, path[0], description, pkg, members}, nil
}

// Transform applies the transformation to the specified parsed file,
// whose type information is supplied in info, and returns the number
// of replacements that were made.
//
// It mutates the AST in place (the identity of the root node is
// unchanged), and may add nodes for which no type information is
// available in info.
//
// Derived from rewriteFile in $GOROOT/src/cmd/gofmt/rewrite.go.
//
func (tr *Transformer) Transform(info *types.Info, pkg *types.Package, file *ast.File) int {
	if !tr.seenInfos[info] {
		tr.seenInfos[info] = true
		mergeTypeInfo(&tr.info.Info, info)
	}
	tr.currentPkg = pkg
	tr.nsubsts = 0

	if tr.verbose {
		fmt.Fprintf(os.Stderr, "before: %s\n", astString(tr.fset, tr.before))
		fmt.Fprintf(os.Stderr, "after: %s\n", astString(tr.fset, tr.after))
	}

	var f func(rv reflect.Value) reflect.Value
	f = func(rv reflect.Value) reflect.Value {
		// don't bother if val is invalid to start with
		if !rv.IsValid() {
			return reflect.Value{}
		}

		rv = apply(f, rv)

		e := rvToExpr(rv)
		if e != nil {
			savedEnv := tr.env
			tr.env = make(map[string]ast.Expr) // inefficient!  Use a slice of k/v pairs

			if tr.matchExpr(tr.before, e) {
				if tr.verbose {
					fmt.Fprintf(os.Stderr, "%s matches %s",
						astString(tr.fset, tr.before), astString(tr.fset, e))
					if len(tr.env) > 0 {
						fmt.Fprintf(os.Stderr, " with:")
						for name, ast := range tr.env {
							fmt.Fprintf(os.Stderr, " %s->%s",
								name, astString(tr.fset, ast))
						}
					}
					fmt.Fprintf(os.Stderr, "\n")
				}
				tr.nsubsts++

				// Clone the replacement tree, performing parameter substitution.
				// We update all positions to n.Pos() to aid comment placement.
				rv = tr.subst(tr.env, reflect.ValueOf(tr.after),
					reflect.ValueOf(e.Pos()))
			}
			tr.env = savedEnv
		}

		return rv
	}
	file2 := apply(f, reflect.ValueOf(file)).Interface().(*ast.File)

	// By construction, the root node is unchanged.
	if file != file2 {
		panic("BUG")
	}

	// Add any necessary imports.
	// TODO(adonovan): remove no-longer needed imports too.
	if tr.nsubsts > 0 {
		pkgs := make(map[string]*types.Package)
		for obj := range tr.importedObjs {
			pkgs[obj.Pkg().Path()] = obj.Pkg()
		}

		for _, imp := range file.Imports {
			path, _ := strconv.Unquote(imp.Path.Value)
			delete(pkgs, path)
		}
		delete(pkgs, pkg.Path()) // don't import self

		// NB: AddImport may completely replace the AST!
		// It thus renders info and tr.info no longer relevant to file.
		var paths []string
		for path := range pkgs {
			paths = append(paths, path)
		}
		sort.Strings(paths)
		for _, path := range paths {
			astutil.AddImport(tr.fset, file, path)
		}
	}

	tr.currentPkg = nil

	return tr.nsubsts
}

func (r *resolver) qualifier(pkg *types.Package) string {
	if pkg == r.pkg {
		return "" // unqualified intra-package reference
	}
	return pkg.Path()
}

func (o *Object) setPkg(p *types.Package) {
	if p != nil {
		o.PkgPath = p.Path()
		o.PkgName = p.Name()
	}
}

func (p *printer) printPackage(pkg *types.Package, filter func(types.Object) bool) {
	// collect objects by kind
	var (
		consts   []*types.Const
		typem    []*types.Named    // non-interface types with methods
		typez    []*types.TypeName // interfaces or types without methods
		vars     []*types.Var
		funcs    []*types.Func
		builtins []*types.Builtin
		methods  = make(map[*types.Named][]*types.Selection) // method sets for named types
	)
	scope := pkg.Scope()
	for _, name := range scope.Names() {
		obj := scope.Lookup(name)
		if obj.Exported() {
			// collect top-level exported and possibly filtered objects
			if filter == nil || filter(obj) {
				switch obj := obj.(type) {
				case *types.Const:
					consts = append(consts, obj)
				case *types.TypeName:
					// group into types with methods and types without
					if named, m := methodsFor(obj); named != nil {
						typem = append(typem, named)
						methods[named] = m
					} else {
						typez = append(typez, obj)
					}
				case *types.Var:
					vars = append(vars, obj)
				case *types.Func:
					funcs = append(funcs, obj)
				case *types.Builtin:
					// for unsafe.Sizeof, etc.
					builtins = append(builtins, obj)
				}
			}
		} else if filter == nil {
			// no filtering: collect top-level unexported types with methods
			if obj, _ := obj.(*types.TypeName); obj != nil {
				// see case *types.TypeName above
				if named, m := methodsFor(obj); named != nil {
					typem = append(typem, named)
					methods[named] = m
				}
			}
		}
	}

	p.printf("package %s  // %q\n", pkg.Name(), pkg.Path())

	p.printDecl("const", len(consts), func() {
		for _, obj := range consts {
			p.printObj(obj)
			p.print("\n")
		}
	})

	p.printDecl("var", len(vars), func() {
		for _, obj := range vars {
			p.printObj(obj)
			p.print("\n")
		}
	})

	p.printDecl("type", len(typez), func() {
		for _, obj := range typez {
			p.printf("%s ", obj.Name())
			p.writeType(p.pkg, obj.Type().Underlying())
			p.print("\n")
		}
	})

	// non-interface types with methods
	for _, named := range typem {
		first := true
		if obj := named.Obj(); obj.Exported() {
			if first {
				p.print("\n")
				first = false
			}
			p.printf("type %s ", obj.Name())
			p.writeType(p.pkg, named.Underlying())
			p.print("\n")
		}
		for _, m := range methods[named] {
			if obj := m.Obj(); obj.Exported() {
				if first {
					p.print("\n")
					first = false
				}
				p.printFunc(m.Recv(), obj.(*types.Func))
				p.print("\n")
			}
		}
	}

	if len(funcs) > 0 {
		p.print("\n")
		for _, obj := range funcs {
//.........这里部分代码省略.........