// Setup configures a *build.Context to use the given VFS
// as its filesystem.
func Setup(ctx *build.Context, fs vfs.VFS) {
ctx.JoinPath = path.Join
ctx.SplitPathList = filepath.SplitList
ctx.IsAbsPath = func(p string) bool {
return p != "" && p[0] == '/'
}
ctx.IsDir = func(p string) bool {
stat, err := fs.Stat(p)
return err == nil && stat.IsDir()
}
ctx.HasSubdir = func(root, dir string) (string, bool) {
root = path.Clean(root)
if !strings.HasSuffix(root, separator) {
root += separator
}
dir = path.Clean(dir)
if !strings.HasPrefix(dir, root) {
return "", false
}
return dir[len(root):], true
}
ctx.ReadDir = fs.ReadDir
ctx.OpenFile = func(p string) (io.ReadCloser, error) {
return fs.Open(p)
}
}
func (w *Walker) setMemoryContext(ctxt *build.Context) {
ctxt.JoinPath = path.Join
ctxt.IsAbsPath = path.IsAbs
ctxt.IsDir = func(path string) bool { panic("unexpected") }
ctxt.HasSubdir = func(root, dir string) (rel string, ok bool) { panic("unexpected") }
ctxt.ReadDir = func(dir string) (fi []os.FileInfo, err error) { return w.readDir(dir) }
ctxt.OpenFile = func(path string) (r io.ReadCloser, err error) { return w.openFile(path) }
}
// Import returns details about the package in the directory.
func (dir *Directory) Import(ctx *build.Context, mode build.ImportMode) (*build.Package, error) {
safeCopy := *ctx
ctx = &safeCopy
ctx.JoinPath = path.Join
ctx.IsAbsPath = path.IsAbs
ctx.SplitPathList = func(list string) []string { return strings.Split(list, ":") }
ctx.IsDir = func(path string) bool { return false }
ctx.HasSubdir = func(root, dir string) (rel string, ok bool) { return "", false }
ctx.ReadDir = dir.readDir
ctx.OpenFile = dir.openFile
return ctx.ImportDir(".", mode)
}
// IsAbsPath behaves like filepath.IsAbs,
// but uses the build context's file system interface, if any.
func IsAbsPath(ctxt *build.Context, path string) bool {
if ctxt.IsAbsPath != nil {
return ctxt.IsAbsPath(path)
}
return filepath.IsAbs(path)
}
func (w *Walker) setLocalContext(ctxt *build.Context) {
ctxt.IsAbsPath = path.IsAbs
}