Suppose you want to test Perl code which uses system() and backticks to invoke commands. These commands are either executable only by the root-user and/or do things you'd rather not do in a test (e.g. rm -rf /).

Does anyone know of an existing way of mocking the system() call and the backtick operator such that they can feed dummy data back to the program instead of doing something unpleasant and returning an error?

I've searched CPAN, this site, and the general internet without any success so far.

I know I can replace system via *CORE::GLOBAL::system, but that doesn't handle backticks. There's the overload module, but that doesn't seem to be able to overload backticks. Finally, I could presumably do it with some XS knowhow, but I'm looking for a pure Perl or off-the-shelf method before I consider going there.

In reply to mocking or trapping system calls by wu-lee

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