brew/Library/Homebrew/rubocops/compact_blank.rb
Issy Long 45978435e7
rubocop: Use Sorbet/StrictSigil as it's better than comments
- 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
```
2024-08-12 15:24:27 +01:00

113 lines
3.9 KiB
Ruby

# typed: true # rubocop:todo Sorbet/StrictSigil
# frozen_string_literal: true
module RuboCop
module Cop
module Homebrew
# Checks if collection can be blank-compacted with `compact_blank`.
#
# NOTE: It is unsafe by default because false positives may occur in the
# blank check of block arguments to the receiver object.
#
# For example, `[[1, 2], [3, nil]].reject { |first, second| second.blank? }` and
# `[[1, 2], [3, nil]].compact_blank` are not compatible. The same is true for `blank?`.
# This will work fine when the receiver is a hash object.
#
# And `compact_blank!` has different implementations for `Array`, `Hash` and
# `ActionController::Parameters`.
# `Array#compact_blank!`, `Hash#compact_blank!` are equivalent to `delete_if(&:blank?)`.
# `ActionController::Parameters#compact_blank!` is equivalent to `reject!(&:blank?)`.
# If the cop makes a mistake, autocorrected code may get unexpected behavior.
#
# ### Examples
#
# ```ruby
# # bad
# collection.reject(&:blank?)
# collection.reject { |_k, v| v.blank? }
#
# # good
# collection.compact_blank
# ```
#
# ```ruby
# # bad
# collection.delete_if(&:blank?) # Same behavior as `Array#compact_blank!` and `Hash#compact_blank!`
# collection.delete_if { |_, v| v.blank? } # Same behavior as `Array#compact_blank!` and `Hash#compact_blank!`
# collection.reject!(&:blank?) # Same behavior as `ActionController::Parameters#compact_blank!`
# collection.reject! { |_k, v| v.blank? } # Same behavior as `ActionController::Parameters#compact_blank!`
#
# # good
# collection.compact_blank!
# ```
class CompactBlank < Base
include RangeHelp
extend AutoCorrector
MSG = "Use `%<preferred_method>s` instead."
RESTRICT_ON_SEND = [:reject, :delete_if, :reject!].freeze
def_node_matcher :reject_with_block?, <<~PATTERN
(block
(send _ {:reject :delete_if :reject!})
$(args ...)
(send
$(lvar _) :blank?))
PATTERN
def_node_matcher :reject_with_block_pass?, <<~PATTERN
(send _ {:reject :delete_if :reject!}
(block_pass
(sym :blank?)))
PATTERN
def on_send(node)
return unless bad_method?(node)
range = offense_range(node)
preferred_method = preferred_method(node)
add_offense(range, message: format(MSG, preferred_method:)) do |corrector|
corrector.replace(range, preferred_method)
end
end
private
def bad_method?(node)
return true if reject_with_block_pass?(node)
if (arguments, receiver_in_block = reject_with_block?(node.parent))
return use_single_value_block_argument?(arguments, receiver_in_block) ||
use_hash_value_block_argument?(arguments, receiver_in_block)
end
false
end
def use_single_value_block_argument?(arguments, receiver_in_block)
arguments.length == 1 && arguments[0].source == receiver_in_block.source
end
def use_hash_value_block_argument?(arguments, receiver_in_block)
arguments.length == 2 && arguments[1].source == receiver_in_block.source
end
def offense_range(node)
end_pos = if node.parent&.block_type? && node.parent&.send_node == node
node.parent.source_range.end_pos
else
node.source_range.end_pos
end
range_between(node.loc.selector.begin_pos, end_pos)
end
def preferred_method(node)
node.method?(:reject) ? "compact_blank" : "compact_blank!"
end
end
end
end
end