Class: Hone::Patterns::CharsMapOrd

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

Overview

Pattern: str.chars.map(&:ord) -> str.codepoints

The .chars.map(&:ord) chain creates an intermediate array of single-char strings, then maps each to its ordinal. Using .codepoints directly is faster and allocates less memory.

From sqids-ruby commit 9413b68

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/chars_map_ord.rb', line 16

def visit_call_node(node)
  super
  # Look for: .map(&:ord) where receiver is .chars
  return unless node.name == :map && block_arg_is_symbol?(node, :ord)

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

  add_finding(
    node,
    message: "Use `.codepoints` instead of `.chars.map(&:ord)` to avoid intermediate array allocation",
    speedup: "Fewer allocations"
  )
end