youssef/debug

Kint - debugging helper for PHP developers

Kint - debugging helper for PHP developers

, _(*1)

, _(*2)

What am I looking at?

At first glance Kint is just a pretty replacement for var_dump(), print_r() and debug_backtrace()., _(*3)

However, it's much, much more than that. Even the excellent xdebug var_dump improvements don't come close - you will eventually wonder how you developed without it., _(*4)

Just to list some of the most useful features:, _(*5)

• The variable name and file + line where Kint was called from is displayed;
• You can disable all Kint output easily and on the fly - so you can even debug live systems without anyone knowing (even though you know you shouldn't be doing that!:).
• CLI is detected and formatted for automatically (but everything can be overridden on the fly) - if your setup supports it, the output is colored too:
  
• Debug backtraces are finally fully readable, actually informative and a pleasure to the eye.
• Kint has been in active development since 2010 and is shipped with Drupal 8 by default as part of its devel suite. You can trust it not being abandoned or getting left behind in features.
• Variable content is displayed in the most informative way - and you never, ever miss anything! Kint guarantees you see every piece of physically available information about everything you are dumping*;
  • ^{in some cases, the content is truncated where it would otherwise be too large to view anyway - but the user is always made aware of that;}
• Some variable content types have an alternative display - for example you will be able see JSON in its raw form - but also as an associative array:
  
  There are more than ten custom variable type displays inbuilt and more are added periodically.

Installation and Usage

One of the main goals of Kint is to be zero setup., _(*6)

Download the archive and simply, _(*7)

<?php
require '/kint/Kint.class.php';

Or, if you use Composer:, _(*8)

"require": {
   "raveren/kint": "^1.0"
}

Or just run composer require raveren/kint, _(*9)

That's it, you can now use Kint to debug your code:, _(*10)

########## DUMP VARIABLE ###########################
Kint::dump($GLOBALS, $_SERVER); // pass any number of parameters

// or simply use d() as a shorthand:
d($_SERVER);


########## DEBUG BACKTRACE #########################
Kint::trace();
// or via shorthand:
d(1);


############# BASIC OUTPUT #########################
# this will show a basic javascript-free display
s($GLOBALS);


######### WHITESPACE FORMATTED OUTPUT ##############
# this will be garbled if viewed in browser as it is whitespace-formatted only
~d($GLOBALS); // just prepend with the tilde


########## MISCELLANEOUS ###########################
# this will disable kint completely
Kint::enabled(false);

ddd('Get off my lawn!'); // no effect

Kint::enabled(true);
ddd( 'this line will stop the execution flow because Kint was just re-enabled above!' );

Note, that Kint does have configuration (like themes and IDE integration!), but it's in need of being rewritten, so I'm not documenting it yet., _(*11)

Tips & Tricks

• Kint is enabled by default, call Kint::enabled(false); to turn its funcionality completely off. The best practice is to enable Kint in DEVELOPMENT environment only (or for example Kint::enabled($_SERVER['REMOTE_ADDR'] === '<your IP>');) - so even if you accidentally leave a dump in production, no one will know.
• sd() and ddd() are shorthands for s();die; and d();die; respectively.
• Kint has keyboard shortcuts! When Kint is visible, press D on the keyboard and you will be able to traverse the tree with arrows and tab keys - and expand/collapse nodes with space or enter.
• Double clicking the [+] sign in the output will expand/collapse ALL nodes; triple clicking big blocks of text will select it all.

• To catch output from Kint just assign it to a variable^beta, _(*12)

  ```php $o = Kint::dump($GLOBALS); // yes, the assignment is automatically detected, and $o // now holds whatever was going to be printed otherwise., <sub>(*13)</sub>

// it also supports modifiers (read on) for the variable: ~$o = Kint::dump($GLOBALS); // this output will be in whitespace, <sub>(*14)</sub>

  * There are a couple of real-time modifiers you can use:
    * `~d($var)` this call will output in plain text format.
    * `+d($var)` will disregard depth level limits and output everything (careful, this can hang your browser on huge objects)
    * `!d($var)` will show expanded rich output.
    * `-d($var)` will attempt to `ob_clean` the previous output so if you're dumping something inside a HTML page, you will still see Kint output.
  You can combine modifiers too: `~+d($var)`
  * To force a specific dump output type just pass it to the `Kint::enabled()` method. Available options are: `Kint::MODE_RICH` (default), `Kint::MODE_PLAIN`, `Kint::MODE_WHITESPACE` and `Kint::MODE_CLI`:

 ```php
Kint::enabled(Kint::MODE_WHITESPACE);
$kintOutput = Kint::dump($GLOBALS);
// now $kintOutput can be written to a text log file and
// be perfectly readable from there

• To change display theme, use Kint::$theme = '<theme name>'; where available options are: 'original' (default), 'solarized', 'solarized-dark' and 'aante-light'. Here's an (outdated) preview:
  

• Kint also includes a naïve profiler you may find handy. It's for determining relatively which code blocks take longer than others:, <sub>(*15)</sub>

  Kint::dump( microtime() ); // just pass microtime()
  sleep( 1 );
  Kint::dump( microtime(), 'after sleep(1)' );
  sleep( 2 );
  ddd( microtime(), 'final call, after sleep(2)' );
  

  , <sub>(*16)</sub>

• See the tiny arrows on the right of the output? Click them (not in the image though :) to open its parent node in a separate browser window.

Author

Rokas Šleinius (raveren), <sub>(*17)</sub>

License

Licensed under the MIT License, <sub>(*18)</sub>