109 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			Go
		
	
	
	
			
		
		
	
	
			109 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			Go
		
	
	
	
package buildutil
 | 
						|
 | 
						|
import (
 | 
						|
	"fmt"
 | 
						|
	"go/build"
 | 
						|
	"io"
 | 
						|
	"io/ioutil"
 | 
						|
	"os"
 | 
						|
	"path"
 | 
						|
	"path/filepath"
 | 
						|
	"sort"
 | 
						|
	"strings"
 | 
						|
	"time"
 | 
						|
)
 | 
						|
 | 
						|
// FakeContext returns a build.Context for the fake file tree specified
 | 
						|
// by pkgs, which maps package import paths to a mapping from file base
 | 
						|
// names to contents.
 | 
						|
//
 | 
						|
// The fake Context has a GOROOT of "/go" and no GOPATH, and overrides
 | 
						|
// the necessary file access methods to read from memory instead of the
 | 
						|
// real file system.
 | 
						|
//
 | 
						|
// Unlike a real file tree, the fake one has only two levels---packages
 | 
						|
// and files---so ReadDir("/go/src/") returns all packages under
 | 
						|
// /go/src/ including, for instance, "math" and "math/big".
 | 
						|
// ReadDir("/go/src/math/big") would return all the files in the
 | 
						|
// "math/big" package.
 | 
						|
//
 | 
						|
func FakeContext(pkgs map[string]map[string]string) *build.Context {
 | 
						|
	clean := func(filename string) string {
 | 
						|
		f := path.Clean(filepath.ToSlash(filename))
 | 
						|
		// Removing "/go/src" while respecting segment
 | 
						|
		// boundaries has this unfortunate corner case:
 | 
						|
		if f == "/go/src" {
 | 
						|
			return ""
 | 
						|
		}
 | 
						|
		return strings.TrimPrefix(f, "/go/src/")
 | 
						|
	}
 | 
						|
 | 
						|
	ctxt := build.Default // copy
 | 
						|
	ctxt.GOROOT = "/go"
 | 
						|
	ctxt.GOPATH = ""
 | 
						|
	ctxt.IsDir = func(dir string) bool {
 | 
						|
		dir = clean(dir)
 | 
						|
		if dir == "" {
 | 
						|
			return true // needed by (*build.Context).SrcDirs
 | 
						|
		}
 | 
						|
		return pkgs[dir] != nil
 | 
						|
	}
 | 
						|
	ctxt.ReadDir = func(dir string) ([]os.FileInfo, error) {
 | 
						|
		dir = clean(dir)
 | 
						|
		var fis []os.FileInfo
 | 
						|
		if dir == "" {
 | 
						|
			// enumerate packages
 | 
						|
			for importPath := range pkgs {
 | 
						|
				fis = append(fis, fakeDirInfo(importPath))
 | 
						|
			}
 | 
						|
		} else {
 | 
						|
			// enumerate files of package
 | 
						|
			for basename := range pkgs[dir] {
 | 
						|
				fis = append(fis, fakeFileInfo(basename))
 | 
						|
			}
 | 
						|
		}
 | 
						|
		sort.Sort(byName(fis))
 | 
						|
		return fis, nil
 | 
						|
	}
 | 
						|
	ctxt.OpenFile = func(filename string) (io.ReadCloser, error) {
 | 
						|
		filename = clean(filename)
 | 
						|
		dir, base := path.Split(filename)
 | 
						|
		content, ok := pkgs[path.Clean(dir)][base]
 | 
						|
		if !ok {
 | 
						|
			return nil, fmt.Errorf("file not found: %s", filename)
 | 
						|
		}
 | 
						|
		return ioutil.NopCloser(strings.NewReader(content)), nil
 | 
						|
	}
 | 
						|
	ctxt.IsAbsPath = func(path string) bool {
 | 
						|
		path = filepath.ToSlash(path)
 | 
						|
		// Don't rely on the default (filepath.Path) since on
 | 
						|
		// Windows, it reports virtual paths as non-absolute.
 | 
						|
		return strings.HasPrefix(path, "/")
 | 
						|
	}
 | 
						|
	return &ctxt
 | 
						|
}
 | 
						|
 | 
						|
type byName []os.FileInfo
 | 
						|
 | 
						|
func (s byName) Len() int           { return len(s) }
 | 
						|
func (s byName) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
 | 
						|
func (s byName) Less(i, j int) bool { return s[i].Name() < s[j].Name() }
 | 
						|
 | 
						|
type fakeFileInfo string
 | 
						|
 | 
						|
func (fi fakeFileInfo) Name() string    { return string(fi) }
 | 
						|
func (fakeFileInfo) Sys() interface{}   { return nil }
 | 
						|
func (fakeFileInfo) ModTime() time.Time { return time.Time{} }
 | 
						|
func (fakeFileInfo) IsDir() bool        { return false }
 | 
						|
func (fakeFileInfo) Size() int64        { return 0 }
 | 
						|
func (fakeFileInfo) Mode() os.FileMode  { return 0644 }
 | 
						|
 | 
						|
type fakeDirInfo string
 | 
						|
 | 
						|
func (fd fakeDirInfo) Name() string    { return string(fd) }
 | 
						|
func (fakeDirInfo) Sys() interface{}   { return nil }
 | 
						|
func (fakeDirInfo) ModTime() time.Time { return time.Time{} }
 | 
						|
func (fakeDirInfo) IsDir() bool        { return true }
 | 
						|
func (fakeDirInfo) Size() int64        { return 0 }
 | 
						|
func (fakeDirInfo) Mode() os.FileMode  { return 0755 }
 |