Vendor

2021-06-01 19:56:34 +02:00
parent e74df463f2
commit 499abe195e
284 changed files with 55166 additions and 0 deletions
@@ -0,0 +1,125 @@
+<?php
+
+declare(strict_types=1);
+
+namespace GraphQL\Validator\Rules;
+
+use GraphQL\Error\Error;
+use GraphQL\Language\AST\FragmentDefinitionNode;
+use GraphQL\Language\AST\FragmentSpreadNode;
+use GraphQL\Language\AST\NodeKind;
+use GraphQL\Language\Visitor;
+use GraphQL\Utils\Utils;
+use GraphQL\Validator\ValidationContext;
+use function array_merge;
+use function array_pop;
+use function array_slice;
+use function count;
+use function implode;
+use function is_array;
+use function sprintf;
+
+class NoFragmentCycles extends ValidationRule
+{
+    /** @var bool[] */
+    public $visitedFrags;
+
+    /** @var FragmentSpreadNode[] */
+    public $spreadPath;
+
+    /** @var (int|null)[] */
+    public $spreadPathIndexByName;
+
+    public function getVisitor(ValidationContext $context)
+    {
+        // Tracks already visited fragments to maintain O(N) and to ensure that cycles
+        // are not redundantly reported.
+        $this->visitedFrags = [];
+
+        // Array of AST nodes used to produce meaningful errors
+        $this->spreadPath = [];
+
+        // Position in the spread path
+        $this->spreadPathIndexByName = [];
+
+        return [
+            NodeKind::OPERATION_DEFINITION => static function () {
+                return Visitor::skipNode();
+            },
+            NodeKind::FRAGMENT_DEFINITION  => function (FragmentDefinitionNode $node) use ($context) {
+                if (! isset($this->visitedFrags[$node->name->value])) {
+                    $this->detectCycleRecursive($node, $context);
+                }
+
+                return Visitor::skipNode();
+            },
+        ];
+    }
+
+    private function detectCycleRecursive(FragmentDefinitionNode $fragment, ValidationContext $context)
+    {
+        $fragmentName                      = $fragment->name->value;
+        $this->visitedFrags[$fragmentName] = true;
+
+        $spreadNodes = $context->getFragmentSpreads($fragment);
+
+        if (empty($spreadNodes)) {
+            return;
+        }
+
+        $this->spreadPathIndexByName[$fragmentName] = count($this->spreadPath);
+
+        for ($i = 0; $i < count($spreadNodes); $i++) {
+            $spreadNode = $spreadNodes[$i];
+            $spreadName = $spreadNode->name->value;
+            $cycleIndex = $this->spreadPathIndexByName[$spreadName] ?? null;
+
+            if ($cycleIndex === null) {
+                $this->spreadPath[] = $spreadNode;
+                if (empty($this->visitedFrags[$spreadName])) {
+                    $spreadFragment = $context->getFragment($spreadName);
+                    if ($spreadFragment) {
+                        $this->detectCycleRecursive($spreadFragment, $context);
+                    }
+                }
+                array_pop($this->spreadPath);
+            } else {
+                $cyclePath = array_slice($this->spreadPath, $cycleIndex);
+                $nodes     = $cyclePath;
+
+                if (is_array($spreadNode)) {
+                    $nodes = array_merge($nodes, $spreadNode);
+                } else {
+                    $nodes[] = $spreadNode;
+                }
+
+                $context->reportError(new Error(
+                    self::cycleErrorMessage(
+                        $spreadName,
+                        Utils::map(
+                            $cyclePath,
+                            static function ($s) {
+                                return $s->name->value;
+                            }
+                        )
+                    ),
+                    $nodes
+                ));
+            }
+        }
+
+        $this->spreadPathIndexByName[$fragmentName] = null;
+    }
+
+    /**
+     * @param string[] $spreadNames
+     */
+    public static function cycleErrorMessage($fragName, array $spreadNames = [])
+    {
+        return sprintf(
+            'Cannot spread fragment "%s" within itself%s.',
+            $fragName,
+            ! empty($spreadNames) ? ' via ' . implode(', ', $spreadNames) : ''
+        );
+    }
+}