Module: SDL2::Debug

Defined in:
lib/sdl2/debug.rb

Overview

This class manages logging output

Constant Summary collapse

ENABLED = 
Hash.new do 
  false # Always defaults to false
end
STATE = 
{
  log_to: STDERR,
  recursion: 0,
  last_caller: [],
}

Class Method Summary collapse

Class Method Details

.enable(obj) ⇒ Object

Takes an instance or a class to enable for debugging. NOTE: If you only enable a single instance, then you will not see messages from the class-level.



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# File 'lib/sdl2/debug.rb', line 37

def self.enable(obj)
  ENABLED[obj] = true
end

.enabled?(obj) ⇒ Boolean

Returns true if the instance It will return true if the object inherits from a class enabled for debugging.

Returns:

  • (Boolean) 


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# File 'lib/sdl2/debug.rb', line 18

def self.enabled?(obj)
  # Immediately return true if we are debugging this instance specifically.
  return true if ENABLED[obj] 
  # Otherwise, check if the object is a class or get it's class.
  klass = obj.kind_of?(Class) ? obj : obj.class
  # And until there is no more superclass.
  until klass == nil
    # Return true if the class is enabled for debugging.
    return true if ENABLED[klass]
    # Otherwise keep searching.
    klass = klass.superclass
  end
  # If we got this far, it is a bust.
  false
end

.log(src, &msg_block) ⇒ Object

This will log a message from a method. The source object is required (usually self) and this is how debugging is controlled. The message must be specified in a block which will never be evaluated unless debugging is enabled for the source. The source class will be identified along with the method name calling log in the output.



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# File 'lib/sdl2/debug.rb', line 46

def self.log(src, &msg_block)
  return unless klass = enabled?(src)
  method_name =  /.*`(.*)'/.match(caller.first)[1]
  is_class = src.kind_of?(Class)
  klass = is_class ? src : src.class
  msg_start = "#{klass.to_s}#{is_class ? '::' : '#'}#{method_name} >"     
  msg = msg_block.nil? ? "No message" : msg_block.call
  STATE[:log_to].puts(caller.first)
  STATE[:log_to].puts(msg_start + msg)
end