Log and break on:
- Object property access
- Method calls
du.js and add it in script tag to your page, which will make all the
the functions (described below) available globally.
I haven't put much consideration into how will this work in node but I use it for running the tests so it should probably work.
$ npm install debug_utils
var du = require('debug_utils'); du.$duv(object, 'foo'); // Make the functions available globally. du.global(); $duv(object, 'bar');
I tried to name the functions so that they're memorable and easy to type. Here are the rules that I followed for naming:
- All functions start with
$duto avoid conflicts.
- Somewhat pronounceable to enable profits via word-of-mouth marketing.
$duthere comes a single letter to hint at the functionality we are debugging. e.g.
$duv, v for events.
lat the end of the function means 'log'. e.g.
$duvl, log events.
rat the end of the function name means 'remove'.
As the complexity of a system grows, evented programming can make it very hard to debug. The following utilities should help you:
Attach an event handler that starts debugger when triggered.
- Making sure the event is being triggered.
- Stepping through other event handlers.
- Finding out what triggered the event.
Attach an event handler that logs its arguments when fired.
- Making sure the event is being fired with the correct args.
Remove previously set debug event handler.
Debugging Property Access
Often times you find that some object is changing from under your feet. And you need to find out what is changing that object. These are utilities for you:
Debug when something tries to get at a
property of an
- Knowing which parts of the code is using your object.
- Tracking the value over calls and time.
$dug but adds logging instead of
Removes getters set by
Debug when something tries to set a
property on an
- Knowing which parts of the code is mutating yo shit.
- Tracking values set over time.
$dus but adds logging instead of
Removes setters set by
Debug both getter and setter. It's like calling
$dus on an object.
$dugs but adds logging instead.
Removes getters and setters set by
unmonitor: logs function calls.
undebug: adds a breakpoint on the first line of the function.
However, they don't work for native methods. The following should help:
Wraps an object's method with a wrapper function with a
- Debugging native methods:
$dum but logs arguments instead.
Removes debug or log wrappers added by
For APIs taking callbacks, it's really useful to be able to drop in a logger or a debugger statement. The following functions are shorter to type out:
A function with a debugger statement.
xhr.onreadystatechange = $dudebug;
- Making sure callbacks are being called.
- Breaking on callback.
p.s. no pun intended.
$dudebug but logs it's arguments instead of breaking.
When called returns a function that logs it's arguments prefixed with
xhr.onreadystatechange = $dulogm('xhr readystate change');
Copyright (c) 2014 Amjad Masad firstname.lastname@example.org