52988: Adds tests for get bookmark

[hellofromtonya]

Trac ticket: https://core.trac.wordpress.org/ticket/52988

Adds unit tests for get_bookmark().

The tests are broken up by the logic path through the if/elseif/else branches.

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This Pull Request is for code review only. Please keep all other discussion in the Trac ticket. Do not merge this Pull Request. See GitHub Pull Requests for Code Review in the Core Handbook for more details.

[peterwilsoncc]

As always, this is lovely.

As always, I've added a few minor questions and comments inline but nothing major.

[peterwilsoncc]

This looks good to me.

It looks like there was an accidental change to package-lock.json included in 3111683 but I'll preapprove as it's really the committers responsibility to check against these things.

[hellofromtonya]

It looks like there was an accidental change to package-lock.json included in 3111683 but I'll preapprove as it's really the committers responsibility to check against these things.

Yup, I did. Doh. Way too easy to accidentally commit lock file. Luckily, it's straightforward for the core committer to skip over that file and only commit the test file.

Thanks @peterwilsoncc!

[peterwilsoncc]

Committed as https://core.trac.wordpress.org/changeset/50789