This adds a `UsesOnSystem` class to `OnSystem`, containing boolean
instance variables to indicate which types of on_system methods are
used in a formula or cask. This is intended as a replacement for
`@on_system_blocks_exist`, which doesn't allow us to determine what
kinds of on_system calls were used. This provides more granularity
but we can still use `@uses_on_system.present?` to determine whether
any on_system calls were used (and this doubles as a `nil` check in
`Formula`, as the `self.class` instance variable has to use a nilable
type).
The `UsesOnSystem` instance variables cover the current
`ARCH_OPTIONS` and `BASE_OS_OPTIONS`. At the moment, we mostly need
to tell whether there are macOS/Linux or Intel/ARM on_system calls,
so I've omitted instance variables for specific macOS version until
we have a need for them.
As a practical example, if you wanted to determine whether a cask
uses Linux on_system calls, you can call
`cask.uses_on_system.linux?`. The `linux` boolean will be `true` if
the cask has an `on_linux` block, an `on_system` block (which requires
Linux), or uses `os linux: ...`. This is something that would be
challenging to determine from outside of `OnSystem` but it's
relatively easy to collect the information in `OnSystem` methods and
make it available like this.
- Previously I thought that comments were fine to discourage people from
wasting their time trying to bump things that used `undef` that Sorbet
didn't support. But RuboCop is better at this since it'll complain if
the comments are unnecessary.
- Suggested in https://github.com/Homebrew/brew/pull/18018#issuecomment-2283369501.
- I've gone for a mixture of `rubocop:disable` for the files that can't
be `typed: strict` (use of undef, required before everything else, etc)
and `rubocop:todo` for everything else that should be tried to make
strictly typed. There's no functional difference between the two as
`rubocop:todo` is `rubocop:disable` with a different name.
- And I entirely disabled the cop for the docs/ directory since
`typed: strict` isn't going to gain us anything for some Markdown
linting config files.
- This means that now it's easier to track what needs to be done rather
than relying on checklists of files in our big Sorbet issue:
```shell
$ git grep 'typed: true # rubocop:todo Sorbet/StrictSigil' | wc -l
268
```
- And this is confirmed working for new files:
```shell
$ git status
On branch use-rubocop-for-sorbet-strict-sigils
Untracked files:
(use "git add <file>..." to include in what will be committed)
Library/Homebrew/bad.rb
Library/Homebrew/good.rb
nothing added to commit but untracked files present (use "git add" to track)
$ brew style
Offenses:
bad.rb:1:1: C: Sorbet/StrictSigil: Sorbet sigil should be at least strict got true.
^^^^^^^^^^^^^
1340 files inspected, 1 offense detected
```
- keep running the command against all os/arch combinations
as the default
- remove todos and deprecations related to changing the behavior
- create constants for os/arch combinations
We don't want to define `MacOS` in the generic OS, so let's make sure we
refer to it as `OS::Mac` in the places we need it.
This reverts commit 575cb0263cb1428c63b9428bbd913ffde83bd317.