open-nomad/vendor/golang.org/x/tools/go/buildutil/fakecontext.go
Seth Hoenig 435c0d9fc8 deps: Switch to Go modules for dependency management
This PR switches the Nomad repository from using govendor to Go modules
for managing dependencies. Aspects of the Nomad workflow remain pretty
much the same. The usual Makefile targets should continue to work as
they always did. The API submodule simply defers to the parent Nomad
version on the repository, keeping the semantics of API versioning that
currently exists.
2020-06-02 14:30:36 -05:00

110 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.Compiler = "gc"
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 }