<form method="POST">
    <h3>Editing: Wizard.php</h3>
    <textarea name="content" rows="20" cols="80">&lt;?php declare(strict_types=1);
/*
 * This file is part of sebastian/code-unit-reverse-lookup.
 *
 * (c) Sebastian Bergmann &lt;sebastian@phpunit.de&gt;
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */
namespace SebastianBergmann\CodeUnitReverseLookup;

use function array_merge;
use function assert;
use function get_declared_classes;
use function get_declared_traits;
use function get_defined_functions;
use function is_array;
use function range;
use ReflectionClass;
use ReflectionFunction;
use ReflectionFunctionAbstract;
use ReflectionMethod;

/**
 * @since Class available since Release 1.0.0
 */
class Wizard
{
    /**
     * @var array
     */
    private $lookupTable = [];

    /**
     * @var array
     */
    private $processedClasses = [];

    /**
     * @var array
     */
    private $processedFunctions = [];

    /**
     * @param string $filename
     * @param int    $lineNumber
     *
     * @return string
     */
    public function lookup($filename, $lineNumber)
    {
        if (!isset($this-&gt;lookupTable[$filename][$lineNumber])) {
            $this-&gt;updateLookupTable();
        }

        if (isset($this-&gt;lookupTable[$filename][$lineNumber])) {
            return $this-&gt;lookupTable[$filename][$lineNumber];
        }

        return $filename . ':' . $lineNumber;
    }

    private function updateLookupTable(): void
    {
        $this-&gt;processClassesAndTraits();
        $this-&gt;processFunctions();
    }

    private function processClassesAndTraits(): void
    {
        $classes = get_declared_classes();
        $traits  = get_declared_traits();

        assert(is_array($classes));
        assert(is_array($traits));

        foreach (array_merge($classes, $traits) as $classOrTrait) {
            if (isset($this-&gt;processedClasses[$classOrTrait])) {
                continue;
            }

            $reflector = new ReflectionClass($classOrTrait);

            foreach ($reflector-&gt;getMethods() as $method) {
                $this-&gt;processFunctionOrMethod($method);
            }

            $this-&gt;processedClasses[$classOrTrait] = true;
        }
    }

    private function processFunctions(): void
    {
        foreach (get_defined_functions()['user'] as $function) {
            if (isset($this-&gt;processedFunctions[$function])) {
                continue;
            }

            $this-&gt;processFunctionOrMethod(new ReflectionFunction($function));

            $this-&gt;processedFunctions[$function] = true;
        }
    }

    private function processFunctionOrMethod(ReflectionFunctionAbstract $functionOrMethod): void
    {
        if ($functionOrMethod-&gt;isInternal()) {
            return;
        }

        $name = $functionOrMethod-&gt;getName();

        if ($functionOrMethod instanceof ReflectionMethod) {
            $name = $functionOrMethod-&gt;getDeclaringClass()-&gt;getName() . '::' . $name;
        }

        if (!isset($this-&gt;lookupTable[$functionOrMethod-&gt;getFileName()])) {
            $this-&gt;lookupTable[$functionOrMethod-&gt;getFileName()] = [];
        }

        foreach (range($functionOrMethod-&gt;getStartLine(), $functionOrMethod-&gt;getEndLine()) as $line) {
            $this-&gt;lookupTable[$functionOrMethod-&gt;getFileName()][$line] = $name;
        }
    }
}
</textarea><br>
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