Fix tests by using `solve_ip(x)`

[averissimo]

Motivation

I was thinking on a way to test some of the changes I've been making and realized that tests were outdated.

None of the tests were passing, I corrected them and simplified the code to remove repetitive lines that are difficult to support.

note: this PR is not included in the other one to avoid having 1 big PR.

Current status

Not all of the tests currently pass (pre or post-simplification), but it might be the Remotes bug you mentioned or something else that I need to correct.

Regardless these tests should be correct.

Changes description

• Tests was very outdated with x$solve() being used instead of solve_ip()
• Adds local_description() helper
  • Uses {withr::local_*} logic to create a temporary DESCRIPTION file and then remove from disk
  • Supports adding an arbitrary number of imports
  • Supports adding an arbitrary number of remotes
• Adds test_proposal_common() helper
  • Avoids having repetitive code for what is essentially the same testing logic.
  • The function has a bit of complexity but cleans up the tests very well
• Style: adds an ASCII separator between test sections
  • figlet uses a modified figlet script

@pawelru would you prefer to have your branch as the base?

[pawelru]

@pawelru would you prefer to have your branch as the base?

Yes please do change the base.

I am aware that the tests are not so great atm but wanted to do this after all packages will be covered. This is much more important.

[averissimo]

Rebased against training branch and corrected the variable name problem you identified! Thanks

This was a low-effort sidequest that I won't continue for now

However, the tools/fixes here will allow for unit tests of some of the changes I've been adding