env_config: infer HOMEBREW_FORBID_PACKAGES_FROM_PATHS from HOMEBREW_DEVELOPER

[carlocab]

• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't other open Pull Requests for the same change?
• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your changes? Here's an example.
• Have you successfully run brew style with your changes locally?
• Have you successfully run brew typecheck with your changes locally?
• Have you successfully run brew tests with your changes locally?

---

If HOMEBREW_DEVELOPER is not set, then let's make
HOMEBREW_FORBID_PACKAGES_FROM_PATHS default to true.

I used a custom implementation here because we don't currently support
setting defaults for booleans. (See calls to define_method below.)

Closes #18371.

[carlocab]

Since this is a breaking change, we may want to save this for a minor release.

[carlocab]

Looks like a lot of tests will need fixing.

[MikeMcQuaid]

Feels like a good quick win here but a little clunky for long-term.

👍🏻 to ship as-is (with or without suggestion) and iterate.

[MikeMcQuaid]

Suggested change

	ENVS.fetch(:HOMEBREW_FORBID_PACKAGES_FROM_PATHS)
	.fetch(:default)
	.call
	developer?

feels a bit nice?

[github-actions]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.

[github-actions]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.

[carlocab]

I'll get to this late next week (or in the first half of the week following that). Note: I'm not optimistic about being able to fix the test failures, so I may just end up closing this after working on it again.

[github-actions]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.