Class: Hone::Patterns::ReverseEach

Inherits:
Base
  • Object
show all
Defined in:
lib/hone/patterns/reverse_each.rb

Overview

Pattern: array.reverse.each { } -> array.reverse_each { }

Calling .reverse.each creates an intermediate reversed array. Using .reverse_each iterates in reverse order without allocation.

Instance Attribute Summary

Attributes inherited from Base

#findings

Instance Method Summary collapse

Methods inherited from Base

#add_finding, inherited, #initialize, scan_file

Constructor Details

This class inherits a constructor from Hone::Patterns::Base

Instance Method Details

#visit_call_node(node) ⇒ Object 



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# File 'lib/hone/patterns/reverse_each.rb', line 13

def visit_call_node(node)
  super

  # Look for: .each { } where receiver is .reverse
  return unless node.name == :each && block_attached?(node)

  receiver = node.receiver
  return unless receiver.is_a?(Prism::CallNode) && receiver.name == :reverse

  add_finding(
    node,
    message: "Use `.reverse_each { }` instead of `.reverse.each { }` to avoid intermediate array",
    speedup: "Avoids intermediate array allocation"
  )
end