lithium\analysis\Debugger
The Debugger
class provides basic facilities for generating and rendering meta-data about the
state of an application in its current context.
Source
class Debugger {
/**
* Used for temporary closure caching.
*
* @see lithium\analysis\Debugger::_closureDef()
* @var array
*/
protected static $_closureCache = [];
/**
* Outputs a stack trace based on the supplied options.
*
* @param array $options Format for outputting stack trace. Available options are:
* - `'args'`: A boolean indicating if arguments should be included.
* - `'depth'`: The maximum depth of the trace.
* - `'format'`: Either `null`, `'points'` or `'array'`.
* - `'includeScope'`: A boolean indicating if items within scope
* should be included.
* - `'scope'`: Scope for items to include.
* - `'start'`: The depth to start with.
* - `'trace'`: A trace to use instead of generating one.
* @return string|array|null Stack trace formatted according to `'format'` option.
*/
public static function trace(array $options = []) {
$defaults = [
'depth' => 999,
'format' => null,
'args' => false,
'start' => 0,
'scope' => [],
'trace' => [],
'includeScope' => true,
'closures' => true
];
$options += $defaults;
$backtrace = $options['trace'] ?: debug_backtrace();
$scope = $options['scope'];
$count = count($backtrace);
$back = [];
$traceDefault = [
'line' => '??', 'file' => '[internal]', 'class' => null, 'function' => '[main]'
];
for ($i = $options['start']; $i < $count && $i < $options['depth']; $i++) {
$trace = array_merge(['file' => '[internal]', 'line' => '??'], $backtrace[$i]);
$function = '[main]';
if (isset($backtrace[$i + 1])) {
$next = $backtrace[$i + 1] + $traceDefault;
$function = $next['function'];
if (!empty($next['class'])) {
$function = $next['class'] . '::' . $function . '(';
if ($options['args'] && isset($next['args'])) {
$args = array_map(['static', 'export'], $next['args']);
$function .= join(', ', $args);
}
$function .= ')';
}
}
if ($options['closures'] && strpos($function, '{closure}') !== false) {
$function = static::_closureDef($backtrace[$i], $function);
}
if (in_array($function, ['call_user_func_array', 'trigger_error'])) {
continue;
}
$trace['functionRef'] = $function;
if ($options['format'] === 'points' && $trace['file'] !== '[internal]') {
$back[] = ['file' => $trace['file'], 'line' => $trace['line']];
} elseif (is_string($options['format']) && $options['format'] !== 'array') {
$back[] = Text::insert($options['format'], array_map(
function($data) { return is_object($data) ? get_class($data) : $data; },
$trace
));
} elseif (empty($options['format'])) {
$back[] = $function . ' - ' . $trace['file'] . ', line ' . $trace['line'];
} else {
$back[] = $trace;
}
if (!empty($scope) && array_intersect_assoc($scope, $trace) == $scope) {
if (!$options['includeScope']) {
$back = array_slice($back, 0, count($back) - 1);
}
break;
}
}
if ($options['format'] === 'array' || $options['format'] === 'points') {
return $back;
}
return join("\n", $back);
}
/**
* Returns a parseable string representation of a variable.
*
* @param mixed $var The variable to export.
* @return string The exported contents.
*/
public static function export($var) {
$export = var_export($var, true);
if (is_array($var)) {
$replace = [" (", " )", " ", " )", "=> \n\t"];
$with = ["(", ")", "\t", "\t)", "=> "];
$export = str_replace($replace, $with, $export);
}
return $export;
}
/**
* Locates original location of closures.
*
* @param mixed $reference File or class name to inspect.
* @param integer $callLine Line number of class reference.
* @return mixed Returns the line number where the method called is defined.
*/
protected static function _definition($reference, $callLine) {
if (file_exists($reference)) {
foreach (array_reverse(token_get_all(file_get_contents($reference))) as $token) {
if (!is_array($token) || $token[2] > $callLine) {
continue;
}
if ($token[0] === T_FUNCTION) {
return $token[2];
}
}
return;
}
list($class,) = explode('::', $reference);
if (!class_exists($class)) {
return;
}
$classRef = new ReflectionClass($class);
$methodInfo = Inspector::info($reference);
$methodDef = join("\n", Inspector::lines($classRef->getFileName(), range(
$methodInfo['start'] + 1, $methodInfo['end'] - 1
)));
foreach (array_reverse(token_get_all("<?php {$methodDef} ?>")) as $token) {
if (!is_array($token) || $token[2] > $callLine) {
continue;
}
if ($token[0] === T_FUNCTION) {
return $token[2] + $methodInfo['start'];
}
}
}
/**
* Helper method for caching closure function references to help the process of building the
* stack trace.
*
* @param array $frame Backtrace information.
* @param callable|string $function The method related to $frame information.
* @return string Returns either the cached or the fetched closure function reference while
* writing its reference to the cache array `$_closureCache`.
*/
protected static function _closureDef($frame, $function) {
$reference = '::';
$frame += ['file' => '??', 'line' => '??'];
$cacheKey = "{$frame['file']}@{$frame['line']}";
if (isset(static::$_closureCache[$cacheKey])) {
return static::$_closureCache[$cacheKey];
}
if ($class = Inspector::classes(['file' => $frame['file']])) {
foreach (Inspector::methods(key($class), 'extents') as $method => $extents) {
$line = $frame['line'];
if (!($extents[0] <= $line && $line <= $extents[1])) {
continue;
}
$class = key($class);
$reference = "{$class}::{$method}";
$function = "{$reference}()::{closure}";
break;
}
} else {
$reference = $frame['file'];
$function = "{$reference}::{closure}";
}
$line = static::_definition($reference, $frame['line']) ?: '?';
$function .= " @ {$line}";
return static::$_closureCache[$cacheKey] = $function;
}
}