| 1 | // Copyright 2018 The Go Authors. All rights reserved. |
|---|---|
| 2 | // Use of this source code is governed by a BSD-style |
| 3 | // license that can be found in the LICENSE file. |
| 4 | |
| 5 | package packages |
| 6 | |
| 7 | import ( |
| 8 | "fmt" |
| 9 | "os" |
| 10 | "sort" |
| 11 | ) |
| 12 | |
| 13 | // Visit visits all the packages in the import graph whose roots are |
| 14 | // pkgs, calling the optional pre function the first time each package |
| 15 | // is encountered (preorder), and the optional post function after a |
| 16 | // package's dependencies have been visited (postorder). |
| 17 | // The boolean result of pre(pkg) determines whether |
| 18 | // the imports of package pkg are visited. |
| 19 | func Visit(pkgs []*Package, pre func(*Package) bool, post func(*Package)) { |
| 20 | seen := make(map[*Package]bool) |
| 21 | var visit func(*Package) |
| 22 | visit = func(pkg *Package) { |
| 23 | if !seen[pkg] { |
| 24 | seen[pkg] = true |
| 25 | |
| 26 | if pre == nil || pre(pkg) { |
| 27 | paths := make([]string, 0, len(pkg.Imports)) |
| 28 | for path := range pkg.Imports { |
| 29 | paths = append(paths, path) |
| 30 | } |
| 31 | sort.Strings(paths) // Imports is a map, this makes visit stable |
| 32 | for _, path := range paths { |
| 33 | visit(pkg.Imports[path]) |
| 34 | } |
| 35 | } |
| 36 | |
| 37 | if post != nil { |
| 38 | post(pkg) |
| 39 | } |
| 40 | } |
| 41 | } |
| 42 | for _, pkg := range pkgs { |
| 43 | visit(pkg) |
| 44 | } |
| 45 | } |
| 46 | |
| 47 | // PrintErrors prints to os.Stderr the accumulated errors of all |
| 48 | // packages in the import graph rooted at pkgs, dependencies first. |
| 49 | // PrintErrors returns the number of errors printed. |
| 50 | func PrintErrors(pkgs []*Package) int { |
| 51 | var n int |
| 52 | Visit(pkgs, nil, func(pkg *Package) { |
| 53 | for _, err := range pkg.Errors { |
| 54 | fmt.Fprintln(os.Stderr, err) |
| 55 | n++ |
| 56 | } |
| 57 | }) |
| 58 | return n |
| 59 | } |
| 60 |
Members