Class: Hone::Patterns::SortByLast

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

Overview

Pattern: array.sort_by { }.last -> array.max_by { }

sort_by { block }.last sorts the entire array then takes the last element. max_by { block } directly finds the maximum without creating intermediate array.

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/sort_by_last.rb', line 13

def visit_call_node(node)
  super

  # Look for: .last where receiver is .sort_by { block }
  return unless node.name == :last && node.arguments.nil?

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

  add_finding(
    node,
    message: "Use `.max_by { }` instead of `.sort_by { }.last` to avoid sorting entire array",
    speedup: "Avoids sorting entire array"
  )
end