Viewing file:  Options.php (15.14 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\OptionsResolver;
use Symfony\Component\OptionsResolver\Exception\OptionDefinitionException;
/**
* Container for resolving inter-dependent options.
*
* @author Bernhard Schussek <bschussek@gmail.com>
*/
class Options implements \ArrayAccess, \Iterator, \Countable
{
/**
* A list of option values.
* @var array
*/
private $options = array();
/**
* A list of normalizer closures.
* @var array
*/
private $normalizers = array();
/**
* A list of closures for evaluating lazy options.
* @var array
*/
private $lazy = array();
/**
* A list containing the currently locked options.
* @var array
*/
private $lock = array();
/**
* Whether at least one option has already been read.
*
* Once read, the options cannot be changed anymore. This is
* necessary in order to avoid inconsistencies during the resolving
* process. If any option is changed after being read, all evaluated
* lazy options that depend on this option would become invalid.
*
* @var Boolean
*/
private $reading = false;
/**
* Sets the value of a given option.
*
* You can set lazy options by passing a closure with the following
* signature:
*
* <code>
* function (Options $options)
* </code>
*
* This closure will be evaluated once the option is read using
* {@link get()}. The closure has access to the resolved values of
* other options through the passed {@link Options} instance.
*
* @param string $option The name of the option.
* @param mixed $value The value of the option.
*
* @throws OptionDefinitionException If options have already been read.
* Once options are read, the container
* becomes immutable.
*/
public function set($option, $value)
{
// Setting is not possible once an option is read, because then lazy
// options could manipulate the state of the object, leading to
// inconsistent results.
if ($this->reading) {
throw new OptionDefinitionException('Options cannot be set anymore once options have been read.');
}
// Setting is equivalent to overloading while discarding the previous
// option value
unset($this->options[$option]);
unset($this->lazy[$option]);
$this->overload($option, $value);
}
/**
* Sets the normalizer for a given option.
*
* Normalizers should be closures with the following signature:
*
* <code>
* function (Options $options, $value)
* </code>
*
* This closure will be evaluated once the option is read using
* {@link get()}. The closure has access to the resolved values of
* other options through the passed {@link Options} instance.
*
* @param string $option The name of the option.
* @param \Closure $normalizer The normalizer.
*
* @throws OptionDefinitionException If options have already been read.
* Once options are read, the container
* becomes immutable.
*/
public function setNormalizer($option, \Closure $normalizer)
{
if ($this->reading) {
throw new OptionDefinitionException('Normalizers cannot be added anymore once options have been read.');
}
$this->normalizers[$option] = $normalizer;
}
/**
* Replaces the contents of the container with the given options.
*
* This method is a shortcut for {@link clear()} with subsequent
* calls to {@link set()}.
*
* @param array $options The options to set.
*
* @throws OptionDefinitionException If options have already been read.
* Once options are read, the container
* becomes immutable.
*/
public function replace(array $options)
{
if ($this->reading) {
throw new OptionDefinitionException('Options cannot be replaced anymore once options have been read.');
}
$this->options = array();
$this->lazy = array();
$this->normalizers = array();
foreach ($options as $option => $value) {
$this->overload($option, $value);
}
}
/**
* Overloads the value of a given option.
*
* Contrary to {@link set()}, this method keeps the previous default
* value of the option so that you can access it if you pass a closure.
* Passed closures should have the following signature:
*
* <code>
* function (Options $options, $value)
* </code>
*
* The second parameter passed to the closure is the current default
* value of the option.
*
* @param string $option The option name.
* @param mixed $value The option value.
*
* @throws OptionDefinitionException If options have already been read.
* Once options are read, the container
* becomes immutable.
*/
public function overload($option, $value)
{
if ($this->reading) {
throw new OptionDefinitionException('Options cannot be overloaded anymore once options have been read.');
}
// If an option is a closure that should be evaluated lazily, store it
// in the "lazy" property.
if ($value instanceof \Closure) {
$reflClosure = new \ReflectionFunction($value);
$params = $reflClosure->getParameters();
if (isset($params[0]) && null !== ($class = $params[0]->getClass()) && __CLASS__ === $class->name) {
// Initialize the option if no previous value exists
if (!isset($this->options[$option])) {
$this->options[$option] = null;
}
// Ignore previous lazy options if the closure has no second parameter
if (!isset($this->lazy[$option]) || !isset($params[1])) {
$this->lazy[$option] = array();
}
// Store closure for later evaluation
$this->lazy[$option][] = $value;
return;
}
}
// Remove lazy options by default
unset($this->lazy[$option]);
$this->options[$option] = $value;
}
/**
* Returns the value of the given option.
*
* If the option was a lazy option, it is evaluated now.
*
* @param string $option The option name.
*
* @return mixed The option value.
*
* @throws \OutOfBoundsException If the option does not exist.
* @throws OptionDefinitionException If a cyclic dependency is detected
* between two lazy options.
*/
public function get($option)
{
$this->reading = true;
if (!array_key_exists($option, $this->options)) {
throw new \OutOfBoundsException(sprintf('The option "%s" does not exist.', $option));
}
if (isset($this->lazy[$option])) {
$this->resolve($option);
}
if (isset($this->normalizers[$option])) {
$this->normalize($option);
}
return $this->options[$option];
}
/**
* Returns whether the given option exists.
*
* @param string $option The option name.
*
* @return Boolean Whether the option exists.
*/
public function has($option)
{
return array_key_exists($option, $this->options);
}
/**
* Removes the option with the given name.
*
* @param string $option The option name.
*
* @throws OptionDefinitionException If options have already been read.
* Once options are read, the container
* becomes immutable.
*/
public function remove($option)
{
if ($this->reading) {
throw new OptionDefinitionException('Options cannot be removed anymore once options have been read.');
}
unset($this->options[$option]);
unset($this->lazy[$option]);
unset($this->normalizers[$option]);
}
/**
* Removes all options.
*
* @throws OptionDefinitionException If options have already been read.
* Once options are read, the container
* becomes immutable.
*/
public function clear()
{
if ($this->reading) {
throw new OptionDefinitionException('Options cannot be cleared anymore once options have been read.');
}
$this->options = array();
$this->lazy = array();
$this->normalizers = array();
}
/**
* Returns the values of all options.
*
* Lazy options are evaluated at this point.
*
* @return array The option values.
*/
public function all()
{
$this->reading = true;
// Performance-wise this is slightly better than
// while (null !== $option = key($this->lazy))
foreach ($this->lazy as $option => $closures) {
// Double check, in case the option has already been resolved
// by cascade in the previous cycles
if (isset($this->lazy[$option])) {
$this->resolve($option);
}
}
foreach ($this->normalizers as $option => $normalizer) {
if (isset($this->normalizers[$option])) {
$this->normalize($option);
}
}
return $this->options;
}
/**
* Equivalent to {@link has()}.
*
* @param string $option The option name.
*
* @return Boolean Whether the option exists.
*
* @see \ArrayAccess::offsetExists()
*/
public function offsetExists($option)
{
return $this->has($option);
}
/**
* Equivalent to {@link get()}.
*
* @param string $option The option name.
*
* @return mixed The option value.
*
* @throws \OutOfBoundsException If the option does not exist.
* @throws OptionDefinitionException If a cyclic dependency is detected
* between two lazy options.
*
* @see \ArrayAccess::offsetGet()
*/
public function offsetGet($option)
{
return $this->get($option);
}
/**
* Equivalent to {@link set()}.
*
* @param string $option The name of the option.
* @param mixed $value The value of the option. May be a closure with a
* signature as defined in DefaultOptions::add().
*
* @throws OptionDefinitionException If options have already been read.
* Once options are read, the container
* becomes immutable.
*
* @see \ArrayAccess::offsetSet()
*/
public function offsetSet($option, $value)
{
$this->set($option, $value);
}
/**
* Equivalent to {@link remove()}.
*
* @param string $option The option name.
*
* @throws OptionDefinitionException If options have already been read.
* Once options are read, the container
* becomes immutable.
*
* @see \ArrayAccess::offsetUnset()
*/
public function offsetUnset($option)
{
$this->remove($option);
}
/**
* {@inheritdoc}
*/
public function current()
{
return $this->get($this->key());
}
/**
* {@inheritdoc}
*/
public function next()
{
next($this->options);
}
/**
* {@inheritdoc}
*/
public function key()
{
return key($this->options);
}
/**
* {@inheritdoc}
*/
public function valid()
{
return null !== $this->key();
}
/**
* {@inheritdoc}
*/
public function rewind()
{
reset($this->options);
}
/**
* {@inheritdoc}
*/
public function count()
{
return count($this->options);
}
/**
* Evaluates the given lazy option.
*
* The evaluated value is written into the options array. The closure for
* evaluating the option is discarded afterwards.
*
* @param string $option The option to evaluate.
*
* @throws OptionDefinitionException If the option has a cyclic dependency
* on another option.
*/
private function resolve($option)
{
// The code duplication with normalize() exists for performance
// reasons, in order to save a method call.
// Remember that this method is potentially called a couple of thousand
// times and needs to be as efficient as possible.
if (isset($this->lock[$option])) {
$conflicts = array();
foreach ($this->lock as $option => $locked) {
if ($locked) {
$conflicts[] = $option;
}
}
throw new OptionDefinitionException(sprintf('The options "%s" have a cyclic dependency.', implode('", "', $conflicts)));
}
$this->lock[$option] = true;
foreach ($this->lazy[$option] as $closure) {
$this->options[$option] = $closure($this, $this->options[$option]);
}
unset($this->lock[$option]);
// The option now isn't lazy anymore
unset($this->lazy[$option]);
}
/**
* Normalizes the given option.
*
* The evaluated value is written into the options array.
*
* @param string $option The option to normalizer.
*
* @throws OptionDefinitionException If the option has a cyclic dependency
* on another option.
*/
private function normalize($option)
{
// The code duplication with resolve() exists for performance
// reasons, in order to save a method call.
// Remember that this method is potentially called a couple of thousand
// times and needs to be as efficient as possible.
if (isset($this->lock[$option])) {
$conflicts = array();
foreach ($this->lock as $option => $locked) {
if ($locked) {
$conflicts[] = $option;
}
}
throw new OptionDefinitionException(sprintf('The options "%s" have a cyclic dependency.', implode('", "', $conflicts)));
}
/** @var \Closure $normalizer */
$normalizer = $this->normalizers[$option];
$this->lock[$option] = true;
$this->options[$option] = $normalizer($this, array_key_exists($option, $this->options) ? $this->options[$option] : null);
unset($this->lock[$option]);
// The option is now normalized
unset($this->normalizers[$option]);
}
}
|