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<?php |
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declare(strict_types=1); |
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namespace TYPO3Fluid\Fluid\Core\ViewHelper; |
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/* |
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* This file belongs to the package "TYPO3 Fluid". |
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* See LICENSE.txt that was shipped with this package. |
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*/ |
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use TYPO3Fluid\Fluid\Component\ComponentInterface; |
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use TYPO3Fluid\Fluid\Component\Error\ChildNotFoundException; |
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use TYPO3Fluid\Fluid\Core\Parser\Exception; |
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use TYPO3Fluid\Fluid\Core\Parser\SyntaxTree\AtomNode; |
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use TYPO3Fluid\Fluid\Core\Parser\SyntaxTree\ReferenceNode; |
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use TYPO3Fluid\Fluid\Core\Rendering\RenderingContextInterface; |
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/** |
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* Class ViewHelperResolver |
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* |
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* Responsible for resolving instances of ViewHelpers and for |
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* interacting with ViewHelpers; to translate ViewHelper names |
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* into actual class names and resolve their ArgumentDefinitions. |
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* |
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* Replacing this class in for example a framework allows that |
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* framework to be responsible for creating ViewHelper instances |
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* and detecting possible arguments. |
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*/ |
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class ViewHelperResolver |
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{ |
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/** |
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* @var RenderingContextInterface |
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*/ |
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protected $renderingContext; |
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/** |
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* @var array |
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*/ |
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protected $resolvedViewHelperClassNames = []; |
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/** |
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* Atom paths indexed by namespace, in |
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* [shortname => [path1, path2, ...]] format. |
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* @var array |
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*/ |
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protected $atoms = []; |
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/** |
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* Namespaces requested by the template being rendered, |
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* in [shortname => [phpnamespace1, phpnamespace2, ...]] format. |
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* |
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* @var array |
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*/ |
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protected $namespaces = [ |
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'f' => ['TYPO3Fluid\\Fluid\\ViewHelpers'] |
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]; |
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/** |
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* @var array |
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*/ |
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protected $aliases = [ |
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'html' => ['f', 'html'], |
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'raw' => ['f', 'format.raw'], |
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]; |
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public function __construct(RenderingContextInterface $renderingContext) |
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{ |
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$this->renderingContext = $renderingContext; |
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} |
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public function addAtomPath(string $namespace, string $path): void |
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{ |
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if (!in_array($path, $this->atoms[$namespace] ?? [], true)) { |
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$this->atoms[$namespace][] = $path; |
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} |
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} |
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/** |
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* Add all Atom paths as array-in-array, with the first level key |
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* being the namespace and the value being an array of paths. |
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* |
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* Example: |
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* |
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* $resolver->addAtomPaths( |
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* [ |
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* 'my' => [ |
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* 'path/first/', |
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* 'path/second/', |
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* ], |
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* 'other' => [ |
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* 'path/third/', |
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* ], |
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* ] |
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* ); |
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* |
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* @param iterable|string[][] $paths |
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*/ |
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public function addAtomPaths(iterable $paths): void |
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{ |
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foreach ($paths as $namespace => $collection) { |
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foreach ($collection as $path) { |
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$this->addAtomPath($namespace, $path); |
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} |
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} |
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} |
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public function resolveAtom(string $namespace, string $name): ComponentInterface |
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{ |
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$file = $this->resolveAtomFile($namespace, $name); |
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if (!$file) { |
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$paths = empty($this->atoms[$namespace]) ? 'none' : implode(', ', $this->atoms[$namespace]); |
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throw new ChildNotFoundException( |
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'Atom "' . $namespace . ':' . $name . '" could not be resolved. We looked in: ' . $paths, |
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1564404340 |
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); |
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} |
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return $this->renderingContext->getTemplateParser()->parseFile($file)->setName($namespace . ':' . $name); |
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} |
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public function resolveAtomFile(string $namespace, string $name): ?string |
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{ |
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if (!isset($this->atoms[$namespace])) { |
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return null; |
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} |
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$expectedFileParts = explode('.', $name); |
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foreach (array_reverse($this->atoms[$namespace]) as $path) { |
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$parts = $expectedFileParts; |
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$subPath = $path; |
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while ($expectedFilePart = array_shift($parts)) { |
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$subPath .= '/' . $expectedFilePart; |
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if (!is_dir($subPath)) { |
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break; |
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} |
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} |
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$filePathAndFilename = $subPath . '.html'; |
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if (file_exists($filePathAndFilename)) { |
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return $filePathAndFilename; |
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} |
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} |
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return null; |
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} |
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/** |
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* @return array|string[][] |
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*/ |
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public function getAtoms(): array |
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{ |
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return $this->atoms; |
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} |
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/** |
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* @return array |
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*/ |
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public function getNamespaces(): array |
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{ |
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return $this->namespaces; |
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} |
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/** |
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* Adds an alias of a ViewHelper, allowing you to call for example |
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* |
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* @param string $alias |
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* @param string $namespace |
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* @param string $identifier |
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*/ |
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public function addViewHelperAlias(string $alias, string $namespace, string $identifier) |
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{ |
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$this->aliases[$alias] = [$namespace, $identifier]; |
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} |
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public function isAliasRegistered(string $alias): bool |
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{ |
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return isset($this->aliases[$alias]); |
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} |
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/** |
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* Add a PHP namespace where ViewHelpers can be found and give |
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* it an alias/identifier. |
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* |
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* The provided namespace can be either a single namespace or |
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* an array of namespaces, as strings. The identifier/alias is |
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* always a single, alpha-numeric ASCII string. |
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* |
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* Calling this method multiple times with different PHP namespaces |
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* for the same alias causes that namespace to be *extended*, |
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* meaning that the PHP namespace you provide second, third etc. |
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* are also used in lookups and are used *first*, so that if any |
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* of the namespaces you add contains a class placed and named the |
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* same way as one that exists in an earlier namespace, then your |
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* class gets used instead of the earlier one. |
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* |
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* Example: |
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* |
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* $resolver->addNamespace('my', 'My\Package\ViewHelpers'); |
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* // Any ViewHelpers under this namespace can now be accessed using for example {my:example()} |
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* // Now, assuming you also have an ExampleViewHelper class in a different |
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* // namespace and wish to make that ExampleViewHelper override the other: |
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* $resolver->addNamespace('my', 'My\OtherPackage\ViewHelpers'); |
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* // Now, since ExampleViewHelper exists in both places but the |
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* // My\OtherPackage\ViewHelpers namespace was added *last*, Fluid |
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* // will find and use My\OtherPackage\ViewHelpers\ExampleViewHelper. |
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* |
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* Alternatively, setNamespaces() can be used to reset and redefine |
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* all previously added namespaces - which is great for cases where |
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* you need to remove or replace previously added namespaces. Be aware |
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* that setNamespaces() also removes the default "f" namespace, so |
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* when you use this method you should always include the "f" namespace. |
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* |
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* @param string $identifier |
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* @param string|array $phpNamespace |
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* @return void |
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*/ |
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public function addNamespace(string $identifier, $phpNamespace): void |
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{ |
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if (!array_key_exists($identifier, $this->namespaces) || $this->namespaces[$identifier] === null) { |
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$this->namespaces[$identifier] = $phpNamespace === null ? null : (array) $phpNamespace; |
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} elseif (is_array($phpNamespace)) { |
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$this->namespaces[$identifier] = array_unique(array_merge($this->namespaces[$identifier], $phpNamespace)); |
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} elseif (isset($this->namespaces[$identifier]) && !in_array($phpNamespace, $this->namespaces[$identifier], true)) { |
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$this->namespaces[$identifier][] = $phpNamespace; |
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} |
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$this->resolvedViewHelperClassNames = []; |
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} |
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/** |
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* Wrapper to allow adding namespaces in bulk *without* first |
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* clearing the already added namespaces. Utility method mainly |
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* used in compiled templates, where some namespaces can be added |
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* from outside and some can be added from compiled values. |
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* |
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* @param array $namespaces |
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* @return void |
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*/ |
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public function addNamespaces(array $namespaces): void |
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{ |
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foreach ($namespaces as $identifier => $namespace) { |
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$this->addNamespace($identifier, $namespace); |
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} |
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} |
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public function removeNamespace(string $identifier, $phpNamespace): void |
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{ |
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if (($key = array_search($phpNamespace, $this->namespaces[$identifier], true)) !== false) { |
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unset($this->namespaces[$identifier][$key]); |
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if (empty($this->namespaces[$identifier])) { |
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unset($this->namespaces[$identifier]); |
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} |
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} |
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} |
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/** |
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* Resolves the PHP namespace based on the Fluid xmlns namespace, |
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* which can be either a URL matching the Patterns::NAMESPACEPREFIX |
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* and Patterns::NAMESPACESUFFIX rules, or a PHP namespace. When |
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* namespace is a PHP namespace it is optional to suffix it with |
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* the "\ViewHelpers" segment, e.g. "My\Package" is as valid to |
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* use as "My\Package\ViewHelpers" is. |
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* |
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* @param string $fluidNamespace |
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* @return string |
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*/ |
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public function resolvePhpNamespaceFromFluidNamespace(string $fluidNamespace): string |
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{ |
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$prefix = 'http://typo3.org/ns/'; |
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$suffix = '/ViewHelpers'; |
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$namespace = $fluidNamespace; |
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$suffixLength = strlen($suffix); |
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$phpNamespaceSuffix = str_replace('/', '\\', $suffix); |
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$extractedSuffix = substr($fluidNamespace, 0 - $suffixLength); |
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if (strpos($fluidNamespace, $prefix) === 0 && $extractedSuffix === $suffix) { |
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// convention assumed: URL starts with prefix and ends with suffix |
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$namespace = substr($fluidNamespace, strlen($prefix)); |
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} |
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$namespace = str_replace('/', '\\', $namespace); |
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if (substr($namespace, 0 - strlen($phpNamespaceSuffix)) !== $phpNamespaceSuffix) { |
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$namespace .= $phpNamespaceSuffix; |
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} |
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return $namespace; |
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} |
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/** |
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* Set all namespaces as an array of ['identifier' => ['Php\Namespace1', 'Php\Namespace2']] |
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* namespace definitions. For convenience and legacy support, a |
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* format of ['identifier' => 'Only\Php\Namespace'] is allowed, |
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* but will internally convert the namespace to an array and |
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* allow it to be extended by addNamespace(). |
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* |
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* Note that when using this method the default "f" namespace is |
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* also removed and so must be included in $namespaces or added |
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* after using addNamespace(). Or, add the PHP namespaces that |
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* belonged to "f" as a new alias and use that in your templates. |
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* |
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* Use getNamespaces() to get an array of currently added namespaces. |
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* |
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* @param array $namespaces |
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* @return void |
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*/ |
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public function setNamespaces(array $namespaces): void |
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{ |
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$this->namespaces = []; |
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foreach ($namespaces as $identifier => $phpNamespace) { |
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$this->namespaces[$identifier] = $phpNamespace === null ? null : (array) $phpNamespace; |
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} |
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} |
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/** |
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* Validates the given namespaceIdentifier and returns FALSE |
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* if the namespace is unknown, causing the tag to be rendered |
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* without processing. |
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* |
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* @param string $namespaceIdentifier |
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* @return boolean TRUE if the given namespace is valid, otherwise FALSE |
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*/ |
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public function isNamespaceValid(string $namespaceIdentifier): bool |
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{ |
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if (!array_key_exists($namespaceIdentifier, $this->namespaces)) { |
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return false; |
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} |
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return $this->namespaces[$namespaceIdentifier] !== null && $namespaceIdentifier !== 'this'; |
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} |
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/** |
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* Validates the given namespaceIdentifier and returns FALSE |
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* if the namespace is unknown and not ignored |
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* |
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* @param string $namespaceIdentifier |
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* @return boolean TRUE if the given namespace is valid, otherwise FALSE |
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*/ |
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public function isNamespaceValidOrIgnored(string $namespaceIdentifier): bool |
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{ |
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if ($this->isNamespaceValid($namespaceIdentifier)) { |
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return true; |
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} |
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if (array_key_exists($namespaceIdentifier, $this->namespaces) || array_key_exists($namespaceIdentifier, $this->atoms)) { |
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return true; |
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} |
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return $this->isNamespaceIgnored($namespaceIdentifier); |
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} |
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/** |
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* @param string $namespaceIdentifier |
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* @return boolean |
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*/ |
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public function isNamespaceIgnored(string $namespaceIdentifier): bool |
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{ |
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if (array_key_exists($namespaceIdentifier, $this->namespaces) && $this->namespaces[$namespaceIdentifier] === null) { |
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return true; |
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} |
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foreach (array_keys($this->namespaces) as $existingNamespaceIdentifier) { |
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if (strpos($existingNamespaceIdentifier, '*') === false) { |
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continue; |
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} |
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$pattern = '/' . str_replace(['.', '*'], ['\\.', '[a-zA-Z0-9\.]*'], $existingNamespaceIdentifier) . '/'; |
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if (preg_match($pattern, $namespaceIdentifier) === 1) { |
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return true; |
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} |
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} |
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return false; |
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|
} |
361
|
|
|
|
362
|
|
|
/** |
363
|
|
|
* Resolves a ViewHelper class name by namespace alias and |
364
|
|
|
* Fluid-format identity, e.g. "f" and "format.htmlspecialchars". |
365
|
|
|
* |
366
|
|
|
* Looks in all PHP namespaces which have been added for the |
367
|
|
|
* provided alias, starting in the last added PHP namespace. If |
368
|
|
|
* a ViewHelper class exists in multiple PHP namespaces Fluid |
369
|
|
|
* will detect and use whichever one was added last. |
370
|
|
|
* |
371
|
|
|
* If no ViewHelper class can be detected in any of the added |
372
|
|
|
* PHP namespaces a Fluid Parser Exception is thrown. |
373
|
|
|
* |
374
|
|
|
* @param string|null $namespaceIdentifier |
375
|
|
|
* @param string $methodIdentifier |
376
|
|
|
* @return string|null |
377
|
|
|
* @throws Exception |
378
|
|
|
*/ |
379
|
|
|
public function resolveViewHelperClassName(?string $namespaceIdentifier, string $methodIdentifier): ?string |
380
|
|
|
{ |
381
|
|
|
if ($namespaceIdentifier === 'this') { |
382
|
|
|
return ReferenceNode::class; |
383
|
|
|
} |
384
|
|
|
if (empty($namespaceIdentifier) && isset($this->aliases[$methodIdentifier])) { |
385
|
|
|
list ($namespaceIdentifier, $methodIdentifier) = $this->aliases[$methodIdentifier]; |
386
|
|
|
} |
387
|
|
|
if (!isset($this->resolvedViewHelperClassNames[$namespaceIdentifier][$methodIdentifier])) { |
388
|
|
|
$actualViewHelperClassName = false; |
389
|
|
|
|
390
|
|
|
$explodedViewHelperName = explode('.', $methodIdentifier); |
391
|
|
|
$className = implode('\\', array_map('ucfirst', $explodedViewHelperName)); |
392
|
|
|
$className .= 'ViewHelper'; |
393
|
|
|
|
394
|
|
|
if (!empty($this->namespaces[$namespaceIdentifier])) { |
395
|
|
|
foreach (array_reverse($this->namespaces[$namespaceIdentifier]) as $namespace) { |
396
|
|
|
$name = $namespace . '\\' . $className; |
397
|
|
|
if (class_exists($name)) { |
398
|
|
|
$actualViewHelperClassName = $name; |
399
|
|
|
break; |
400
|
|
|
} |
401
|
|
|
} |
402
|
|
|
} |
403
|
|
|
|
404
|
|
|
if ($actualViewHelperClassName === false) { |
405
|
|
|
|
406
|
|
|
// If namespace and method match an Atom, return AtomNode's class name. Otherwise, error out. |
407
|
|
|
if ($this->resolveAtomFile($namespaceIdentifier, $methodIdentifier)) { |
|
|
|
|
408
|
|
|
return AtomNode::class; |
409
|
|
|
} |
410
|
|
|
|
411
|
|
|
throw new Exception(sprintf( |
412
|
|
|
'A Component named "<%s:%s>" could not be resolved.' . chr(10) . |
413
|
|
|
'We looked in the following namespaces: %s.', |
414
|
|
|
$namespaceIdentifier, |
415
|
|
|
$methodIdentifier, |
416
|
|
|
implode(', ', $this->namespaces[$namespaceIdentifier] ?? ['none']) |
417
|
|
|
), 1407060572); |
418
|
|
|
} |
419
|
|
|
|
420
|
|
|
$this->resolvedViewHelperClassNames[$namespaceIdentifier][$methodIdentifier] = $actualViewHelperClassName; |
421
|
|
|
} |
422
|
|
|
return $this->resolvedViewHelperClassNames[$namespaceIdentifier][$methodIdentifier]; |
423
|
|
|
} |
424
|
|
|
|
425
|
|
|
/** |
426
|
|
|
* Can be overridden by custom implementations to change the way |
427
|
|
|
* classes are loaded when the class is a ViewHelper - for |
428
|
|
|
* example making it possible to use a DI-aware class loader. |
429
|
|
|
* |
430
|
|
|
* If null is passed as namespace, only registered ViewHelper |
431
|
|
|
* aliases are checked against the $viewHelperShortName. |
432
|
|
|
* |
433
|
|
|
* @param string|null $namespace |
434
|
|
|
* @param string $viewHelperShortName |
435
|
|
|
* @return ComponentInterface |
436
|
|
|
*/ |
437
|
|
|
public function createViewHelperInstance(?string $namespace, string $viewHelperShortName): ComponentInterface |
438
|
|
|
{ |
439
|
|
|
if ($namespace === 'this') { |
440
|
|
|
return new ReferenceNode($viewHelperShortName); |
441
|
|
|
} |
442
|
|
|
if (!empty($namespace) && isset($this->atoms[$namespace])) { |
443
|
|
|
$atomFile = $this->resolveAtomFile($namespace, $viewHelperShortName); |
444
|
|
|
if ($atomFile) { |
|
|
|
|
445
|
|
|
return (new AtomNode()) |
446
|
|
|
->setArguments(clone $this->renderingContext->getTemplateParser()->parseFile($atomFile)->getArguments()) |
447
|
|
|
->setFile($atomFile) |
448
|
|
|
->setName($namespace . ':' . $viewHelperShortName); |
449
|
|
|
} |
450
|
|
|
} |
451
|
|
|
$className = $this->resolveViewHelperClassName($namespace, $viewHelperShortName); |
452
|
|
|
$instance = $this->createViewHelperInstanceFromClassName($className); |
453
|
|
|
return $instance; |
454
|
|
|
} |
455
|
|
|
|
456
|
|
|
/** |
457
|
|
|
* Wrapper to create a ViewHelper instance by class name. This is |
458
|
|
|
* the final method called when creating ViewHelper classes - |
459
|
|
|
* overriding this method allows custom constructors, dependency |
460
|
|
|
* injections etc. to be performed on the ViewHelper instance. |
461
|
|
|
* |
462
|
|
|
* @param string $viewHelperClassName |
463
|
|
|
* @return ComponentInterface |
464
|
|
|
*/ |
465
|
|
|
public function createViewHelperInstanceFromClassName(string $viewHelperClassName): ComponentInterface |
466
|
|
|
{ |
467
|
|
|
return new $viewHelperClassName(); |
468
|
|
|
} |
469
|
|
|
} |
470
|
|
|
|
Let’s assume that you have a directory layout like this:
and let’s assume the following content of
Bar.php
:If both files
OtherDir/Foo.php
andSomeDir/Foo.php
are loaded in the same runtime, you will see a PHP error such as the following:PHP Fatal error: Cannot use SomeDir\Foo as Foo because the name is already in use in OtherDir/Foo.php
However, as
OtherDir/Foo.php
does not necessarily have to be loaded and the error is only triggered if it is loaded beforeOtherDir/Bar.php
, this problem might go unnoticed for a while. In order to prevent this error from surfacing, you must import the namespace with a different alias: