status-go/vendor/golang.org/x/lint/golint/import.go

310 lines
8.3 KiB
Go

package main
/*
This file holds a direct copy of the import path matching code of
https://github.com/golang/go/blob/master/src/cmd/go/main.go. It can be
replaced when https://golang.org/issue/8768 is resolved.
It has been updated to follow upstream changes in a few ways.
*/
import (
"fmt"
"go/build"
"log"
"os"
"path"
"path/filepath"
"regexp"
"runtime"
"strings"
)
var (
buildContext = build.Default
goroot = filepath.Clean(runtime.GOROOT())
gorootSrc = filepath.Join(goroot, "src")
)
// importPathsNoDotExpansion returns the import paths to use for the given
// command line, but it does no ... expansion.
func importPathsNoDotExpansion(args []string) []string {
if len(args) == 0 {
return []string{"."}
}
var out []string
for _, a := range args {
// Arguments are supposed to be import paths, but
// as a courtesy to Windows developers, rewrite \ to /
// in command-line arguments. Handles .\... and so on.
if filepath.Separator == '\\' {
a = strings.Replace(a, `\`, `/`, -1)
}
// Put argument in canonical form, but preserve leading ./.
if strings.HasPrefix(a, "./") {
a = "./" + path.Clean(a)
if a == "./." {
a = "."
}
} else {
a = path.Clean(a)
}
if a == "all" || a == "std" {
out = append(out, allPackages(a)...)
continue
}
out = append(out, a)
}
return out
}
// importPaths returns the import paths to use for the given command line.
func importPaths(args []string) []string {
args = importPathsNoDotExpansion(args)
var out []string
for _, a := range args {
if strings.Contains(a, "...") {
if build.IsLocalImport(a) {
out = append(out, allPackagesInFS(a)...)
} else {
out = append(out, allPackages(a)...)
}
continue
}
out = append(out, a)
}
return out
}
// matchPattern(pattern)(name) reports whether
// name matches pattern. Pattern is a limited glob
// pattern in which '...' means 'any string' and there
// is no other special syntax.
func matchPattern(pattern string) func(name string) bool {
re := regexp.QuoteMeta(pattern)
re = strings.Replace(re, `\.\.\.`, `.*`, -1)
// Special case: foo/... matches foo too.
if strings.HasSuffix(re, `/.*`) {
re = re[:len(re)-len(`/.*`)] + `(/.*)?`
}
reg := regexp.MustCompile(`^` + re + `$`)
return func(name string) bool {
return reg.MatchString(name)
}
}
// hasPathPrefix reports whether the path s begins with the
// elements in prefix.
func hasPathPrefix(s, prefix string) bool {
switch {
default:
return false
case len(s) == len(prefix):
return s == prefix
case len(s) > len(prefix):
if prefix != "" && prefix[len(prefix)-1] == '/' {
return strings.HasPrefix(s, prefix)
}
return s[len(prefix)] == '/' && s[:len(prefix)] == prefix
}
}
// treeCanMatchPattern(pattern)(name) reports whether
// name or children of name can possibly match pattern.
// Pattern is the same limited glob accepted by matchPattern.
func treeCanMatchPattern(pattern string) func(name string) bool {
wildCard := false
if i := strings.Index(pattern, "..."); i >= 0 {
wildCard = true
pattern = pattern[:i]
}
return func(name string) bool {
return len(name) <= len(pattern) && hasPathPrefix(pattern, name) ||
wildCard && strings.HasPrefix(name, pattern)
}
}
// allPackages returns all the packages that can be found
// under the $GOPATH directories and $GOROOT matching pattern.
// The pattern is either "all" (all packages), "std" (standard packages)
// or a path including "...".
func allPackages(pattern string) []string {
pkgs := matchPackages(pattern)
if len(pkgs) == 0 {
fmt.Fprintf(os.Stderr, "warning: %q matched no packages\n", pattern)
}
return pkgs
}
func matchPackages(pattern string) []string {
match := func(string) bool { return true }
treeCanMatch := func(string) bool { return true }
if pattern != "all" && pattern != "std" {
match = matchPattern(pattern)
treeCanMatch = treeCanMatchPattern(pattern)
}
have := map[string]bool{
"builtin": true, // ignore pseudo-package that exists only for documentation
}
if !buildContext.CgoEnabled {
have["runtime/cgo"] = true // ignore during walk
}
var pkgs []string
// Commands
cmd := filepath.Join(goroot, "src/cmd") + string(filepath.Separator)
filepath.Walk(cmd, func(path string, fi os.FileInfo, err error) error {
if err != nil || !fi.IsDir() || path == cmd {
return nil
}
name := path[len(cmd):]
if !treeCanMatch(name) {
return filepath.SkipDir
}
// Commands are all in cmd/, not in subdirectories.
if strings.Contains(name, string(filepath.Separator)) {
return filepath.SkipDir
}
// We use, e.g., cmd/gofmt as the pseudo import path for gofmt.
name = "cmd/" + name
if have[name] {
return nil
}
have[name] = true
if !match(name) {
return nil
}
_, err = buildContext.ImportDir(path, 0)
if err != nil {
if _, noGo := err.(*build.NoGoError); !noGo {
log.Print(err)
}
return nil
}
pkgs = append(pkgs, name)
return nil
})
for _, src := range buildContext.SrcDirs() {
if (pattern == "std" || pattern == "cmd") && src != gorootSrc {
continue
}
src = filepath.Clean(src) + string(filepath.Separator)
root := src
if pattern == "cmd" {
root += "cmd" + string(filepath.Separator)
}
filepath.Walk(root, func(path string, fi os.FileInfo, err error) error {
if err != nil || !fi.IsDir() || path == src {
return nil
}
// Avoid .foo, _foo, and testdata directory trees.
_, elem := filepath.Split(path)
if strings.HasPrefix(elem, ".") || strings.HasPrefix(elem, "_") || elem == "testdata" {
return filepath.SkipDir
}
name := filepath.ToSlash(path[len(src):])
if pattern == "std" && (strings.Contains(name, ".") || name == "cmd") {
// The name "std" is only the standard library.
// If the name is cmd, it's the root of the command tree.
return filepath.SkipDir
}
if !treeCanMatch(name) {
return filepath.SkipDir
}
if have[name] {
return nil
}
have[name] = true
if !match(name) {
return nil
}
_, err = buildContext.ImportDir(path, 0)
if err != nil {
if _, noGo := err.(*build.NoGoError); noGo {
return nil
}
}
pkgs = append(pkgs, name)
return nil
})
}
return pkgs
}
// allPackagesInFS is like allPackages but is passed a pattern
// beginning ./ or ../, meaning it should scan the tree rooted
// at the given directory. There are ... in the pattern too.
func allPackagesInFS(pattern string) []string {
pkgs := matchPackagesInFS(pattern)
if len(pkgs) == 0 {
fmt.Fprintf(os.Stderr, "warning: %q matched no packages\n", pattern)
}
return pkgs
}
func matchPackagesInFS(pattern string) []string {
// Find directory to begin the scan.
// Could be smarter but this one optimization
// is enough for now, since ... is usually at the
// end of a path.
i := strings.Index(pattern, "...")
dir, _ := path.Split(pattern[:i])
// pattern begins with ./ or ../.
// path.Clean will discard the ./ but not the ../.
// We need to preserve the ./ for pattern matching
// and in the returned import paths.
prefix := ""
if strings.HasPrefix(pattern, "./") {
prefix = "./"
}
match := matchPattern(pattern)
var pkgs []string
filepath.Walk(dir, func(path string, fi os.FileInfo, err error) error {
if err != nil || !fi.IsDir() {
return nil
}
if path == dir {
// filepath.Walk starts at dir and recurses. For the recursive case,
// the path is the result of filepath.Join, which calls filepath.Clean.
// The initial case is not Cleaned, though, so we do this explicitly.
//
// This converts a path like "./io/" to "io". Without this step, running
// "cd $GOROOT/src/pkg; go list ./io/..." would incorrectly skip the io
// package, because prepending the prefix "./" to the unclean path would
// result in "././io", and match("././io") returns false.
path = filepath.Clean(path)
}
// Avoid .foo, _foo, and testdata directory trees, but do not avoid "." or "..".
_, elem := filepath.Split(path)
dot := strings.HasPrefix(elem, ".") && elem != "." && elem != ".."
if dot || strings.HasPrefix(elem, "_") || elem == "testdata" {
return filepath.SkipDir
}
name := prefix + filepath.ToSlash(path)
if !match(name) {
return nil
}
if _, err = build.ImportDir(path, 0); err != nil {
if _, noGo := err.(*build.NoGoError); !noGo {
log.Print(err)
}
return nil
}
pkgs = append(pkgs, name)
return nil
})
return pkgs
}