way to detecte circular deependencies between components

src/Toolkit/src/Registry/DependenciesResolver.php

@@ -0,0 +1,65 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <[email protected]>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\UX\Toolkit\Registry;
+
+/**
+ * @author Jean-François Lépine
+ *
+ * @internal
+ */
+class DependenciesResolver
+{
+    public function resolve(Registry $registry): array
+    {
+        $resolved = [];
+        $unresolved = [];
+        foreach (array_keys($registry->all()) as $itemName) {
+            [$resolved, $unresolved] = $this->resolveDependency($registry, $itemName, $resolved, $unresolved);
+        }
+
+        $sorted = [];
+        foreach ($resolved as $itemName) {
+            $sorted[] = $registry->get($itemName);
+        }
+
+        return $sorted;
+    }
+
+    private function resolveDependency(Registry $registry, string $itemName, array $resolved, array $unresolved)
+    {
+        $unresolved[] = $itemName;
+        $dependencies = [];
+        if (null !== $registry->get($itemName)->parentName) {
+            $dependencies[] = $registry->get($itemName)->parentName;
+        }
+
+        foreach ($dependencies as $dep) {
+            if (!\in_array($dep, $resolved)) {
+                if (!\in_array($dep, $unresolved)) {
+                    $unresolved[] = $dep;
+                    [$resolved, $unresolved] = $this->resolveDependency($registry, $dep, $resolved, $unresolved);
+                } else {
+                    throw new \RuntimeException("Circular dependency detected: $itemName -> $dep.");
+                }
+            }
+        }
+        if (!\in_array($itemName, $resolved)) {
+            $resolved[] = $itemName;
+        }
+
+        while (($index = array_search($itemName, $unresolved)) !== false) {
+            unset($unresolved[$index]);
+        }
+
+        return [$resolved, $unresolved];
+    }
+}

src/Toolkit/src/Registry/Registry.php

@@ -33,7 +33,15 @@ public static function empty(): self
 
     public function add(RegistryItem $item): void
     {
-        $this->items[] = $item;
+        $this->items[$item->name] = $item;
+    }
+
+    /**
+     * @return RegistryItem[]
+     */
+    public function all(): array
+    {
+        return $this->items;
     }
 
     public function has(string $name): bool

src/Toolkit/tests/Registry/DependenciesResolverTest.php

@@ -0,0 +1,129 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <[email protected]>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\UX\Toolkit\Tests\Registry;
+
+use PHPUnit\Framework\TestCase;
+use Symfony\UX\Toolkit\Registry\DependenciesResolver;
+use Symfony\UX\Toolkit\Registry\Registry;
+use Symfony\UX\Toolkit\Registry\RegistryItem;
+use Symfony\UX\Toolkit\Registry\RegistryItemType;
+
+/**
+ * @author Jean-François Lépine
+ *
+ * @group wip
+ */
+class DependenciesResolverTest extends TestCase
+{
+    public function testItShouldResolveDependenciesOrder(): void
+    {
+        $registry = new Registry();
+
+        $registry->add(
+            new RegistryItem(
+                'cell',
+                RegistryItemType::Component,
+                'default',
+                'row',
+                ''
+            )
+        );
+
+        $registry->add(
+            new RegistryItem(
+                'table',
+                RegistryItemType::Component,
+                'default',
+                null,
+                ''
+            )
+        );
+
+        $registry->add(
+            new RegistryItem(
+                'row',
+                RegistryItemType::Component,
+                'default',
+                'table',
+                ''
+            )
+        );
+
+        $registry->add(
+            new RegistryItem(
+                'button',
+                RegistryItemType::Component,
+                'default',
+                null,
+                ''
+            )
+        );
+
+        $registry->add(
+            new RegistryItem(
+                'icon',
+                RegistryItemType::Component,
+                'default',
+                'button',
+                ''
+            )
+        );
+
+        $resolver = new DependenciesResolver();
+        $resolved = $resolver->resolve($registry);
+        $this->assertEquals('table', $resolved[0]->name);
+        $this->assertEquals('row', $resolved[1]->name);
+        $this->assertEquals('cell', $resolved[2]->name);
+        $this->assertEquals('button', $resolved[3]->name);
+        $this->assertEquals('icon', $resolved[4]->name);
+    }
+
+    public function testCircularDependency(): void
+    {
+        $registry = new Registry();
+
+        $registry->add(
+            new RegistryItem(
+                'cell',
+                RegistryItemType::Component,
+                'default',
+                'row',
+                ''
+            )
+        );
+
+        $registry->add(
+            new RegistryItem(
+                'table',
+                RegistryItemType::Component,
+                'default',
+                'cell',
+                ''
+            )
+        );
+
+        $registry->add(
+            new RegistryItem(
+                'row',
+                RegistryItemType::Component,
+                'default',
+                'table',
+                ''
+            )
+        );
+
+        $resolver = new DependenciesResolver();
+        $this->expectException(\RuntimeException::class);
+        $this->expectExceptionMessage('Circular dependency detected: table -> cell');
+        $resolver->resolve($registry);
+    }
+}