Function existingFileMapper

mapper.go:648–682

(r *Registry)

}

func existingFileMapper(r *Registry) MapperFunc {
	return func(ctx *DecodeContext, target reflect.Value) error {
		if target.Kind() == reflect.Slice {
			return sliceDecoder(r)(ctx, target)
		}
		if target.Kind() != reflect.String {
			return fmt.Errorf("\"existingfile\" type must be applied to a string not %s", target.Type())
		}
		var path string
		err := ctx.Scan.PopValueInto("file", &path)
		if err != nil {
			return err
		}

		if !ctx.Value.Active || (ctx.Value.Set && ctx.Value.Target.Type() == target.Type()) {
			// early return to avoid checking extra files that may not exist;
			// this hack only works because the value provided on the cli is
			// checked before the default value is checked (if default is set).
			return nil
		}

		if path != "-" {
			path = ExpandPath(path)
			stat, err := os.Stat(path)
			if err != nil {
				return err
			}
			if stat.IsDir() {
				return fmt.Errorf("%q exists but is a directory", path)
			}
		}
		target.SetString(path)
		return nil
	}
}

func existingDirMapper(r *Registry) MapperFunc {
	return func(ctx *DecodeContext, target reflect.Value) error {