Class: Hone::Patterns::YieldVsBlock

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

Overview

Pattern: block.call -> yield when method has &block parameter

When a method accepts a block with &block, calling block.call is slower than using yield. The &block syntax converts the block to a Proc object, which has overhead. Using yield avoids this Proc allocation when the block is only called (not stored or passed elsewhere).

Example:

# Before - allocates Proc
def process(&block)
block.call(value)
end

# After - no Proc allocation
def process
yield(value)
end

Impact: Avoids Proc allocation

Instance Attribute Summary

Attributes inherited from Base

#findings

Instance Method Summary collapse

Methods inherited from Base

#add_finding, inherited, scan_file

Constructor Details

#initialize(file_path) ⇒ YieldVsBlock

Returns a new instance of YieldVsBlock.



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# File 'lib/hone/patterns/yield_vs_block.rb', line 28

def initialize(file_path)
  super
  @block_param_name = nil
end

Instance Method Details

#visit_call_node(node) ⇒ Object 



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# File 'lib/hone/patterns/yield_vs_block.rb', line 43

def visit_call_node(node)
  super

  return unless @block_param_name
  return unless node.name == :call

  receiver = node.receiver
  return unless receiver.is_a?(Prism::LocalVariableReadNode)
  return unless receiver.name == @block_param_name

  add_finding(
    node,
    message: "Use `yield` instead of `#{@block_param_name}.call` to avoid Proc allocation",
    speedup: "Avoids Proc allocation"
  )
end

#visit_def_node(node) ⇒ Object 



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# File 'lib/hone/patterns/yield_vs_block.rb', line 33

def visit_def_node(node)
  block_param = find_block_parameter(node.parameters)

  if block_param
    with_context(:@block_param_name, block_param) { super }
  else
    super
  end
end