code: func (m FileMode) IsMalformed() bool {
  	return m != Dir &&
  		m != Regular &&
  		m != Deprecated &&
  		m != Executable &&
  		m != Symlink &&
  		m != Submodule
  }
docs: // IsMalformed returns if the FileMode should not appear in a git packfile,
  // this is: Empty and any other mode not mentioned as a constant in this
  // package.