NewFiles creates two Version handles (i.e., two temporary directories).

NewProgram returns kubectl's default Program implementation that respects the KUBECTL_EXTERNAL_DIFF environment variable.

NewVersion creates a temporary directory.

Files is a compound handle for multiple directories and files that shall be compared using a diff program.

Version is a handle for a directory that can hold multiple files of a single version to compare.

Program is a diff program that compares two files.