Move remaining core specs to use fewer shared examples

[Earlopain]

It's quite chonky but mostly more of the same for #1364. This converts the entirety of core specs.

Before:
3805 files, 35698 examples, 273269 expectations, 0 failure, 0 errors, 0 tagged

After:
3805 files, 34586 examples, 256944 expectations, 0 failure, 0 errors, 0 tagged

1112 fewer specs.

[Copilot]

Copilot wasn't able to review this pull request because it exceeds the maximum number of files (300). Try reducing the number of changed files and requesting a review from Copilot again.

[Earlopain]

Let me split this up in two PRs then

[Copilot]

Pull request overview

Copilot reviewed 150 out of 150 changed files in this pull request and generated 4 comments.

[eregon]

I would prefer the other way around, i.e. map/select/include? are way more used than collect/find_all/member? so I think they should have the specs and the less used aliases should just check they are aliases of the most-used methods.
The other aliases in Enumerable look good in terms of the most-used having the specs.

[eregon]

This is something that could be fixed later, we could merge both PRs and I could review all usages of is an alias of to see which don't match that rule.

[Earlopain]

No need to put this in the blame, I'll take care of it in this PR. It's what rdoc considers the alias but I don't mind choosing the more popular version instead.

I'll do that tomorrow or so, already pretty late for me now.

[Copilot]

Pull request overview

Copilot reviewed 150 out of 150 changed files in this pull request and generated 4 comments.

[Copilot]

Pull request overview

Copilot reviewed 150 out of 150 changed files in this pull request and generated 1 comment.

Comments suppressed due to low confidence (5)

core/io/tty_spec.rb:1

• This spec can be flaky across CI/container environments because /dev/tty may be missing or inaccessible (e.g., Errno::ENOENT, Errno::EACCES, Errno::ENODEV), not just Errno::ENXIO. Consider broadening the rescued errors (or guarding by checking existence/permissions) so the spec reliably skips when TTY access is not available.
  core/file/to_path_spec.rb:1
• This platform_is/guard block defines before/after hooks but contains no examples that use @dir. Either add the missing TMPFILE-related examples within this scope or remove the unused hooks to avoid dead setup code.
  core/float/fdiv_spec.rb:1
• The second example’s description duplicates the first one verbatim, which makes failures harder to interpret. Rename the second description to reflect the distinct intent (e.g., division by a very large Integer).
  core/kernel/dup_spec.rb:1
• The spec that verified #dup calls #initialize_copy was removed, which drops coverage for an important and observable part of Ruby’s object-copying semantics. Consider re-adding an explicit example asserting initialize_copy is invoked (or adding equivalent coverage elsewhere in the same spec suite) so regressions in dup hooks are caught.
  core/kernel/clone_spec.rb:1
• Similarly to dup_spec, removing the initialize_copy expectation for #clone reduces coverage for clone’s copy hook behavior. Re-introduce an example that asserts initialize_copy is called during clone to keep coverage of this user-visible contract.