feat: Add dependentSchemas support

Author: DannyvdSluijs

src/JsonSchema/Constraints/Drafts/Draft2019/DependentSchemasConstraint.php

@@ -0,0 +1,58 @@
+<?php
+
+declare(strict_types=1);
+
+namespace JsonSchema\Constraints\Drafts\Draft2019;
+
+use JsonSchema\ConstraintError;
+use JsonSchema\Constraints\ConstraintInterface;
+use JsonSchema\Entity\ErrorBagProxy;
+use JsonSchema\Entity\JsonPointer;
+
+class DependentSchemasConstraint implements ConstraintInterface
+{
+    use ErrorBagProxy;
+
+    /** @var Factory */
+    private $factory;
+
+    public function __construct(?Factory $factory = null)
+    {
+        $this->factory = $factory ?: new Factory();
+        $this->initialiseErrorBag($this->factory);
+    }
+
+    public function check(&$value, $schema = null, ?JsonPointer $path = null, $i = null): void
+    {
+        if (!property_exists($schema, 'dependentSchemas')) {
+            return;
+        }
+
+        if (!is_object($value)) {
+            return;
+        }
+
+        foreach ($schema->dependentSchemas as $dependant => $dependentSchema) {
+            if (!property_exists($value, $dependant)) {
+                continue;
+            }
+
+            if ($dependentSchema === true) {
+                continue;
+            }
+
+            if ($dependentSchema === false) {
+                $this->addError(ConstraintError::FALSE(), $path, ['dependant' => $dependant]);
+                continue;
+            }
+
+            if (is_object($dependentSchema)) {
+                $schemaConstraint = $this->factory->createInstanceFor('schema');
+                $schemaConstraint->check($value, $dependentSchema, $path, $i);
+                if (!$schemaConstraint->isValid()) {
+                    $this->addErrors($schemaConstraint->getErrors());
+                }
+            }
+        }
+    }
+}

src/JsonSchema/Constraints/Drafts/Draft2019/Draft2019Constraint.php

@@ -41,6 +41,7 @@ public function check(&$value, $schema = null, ?JsonPointer $path = null, $i = n
         $this->checkForKeyword('type', $value, $schema, $path, $i);
         $this->checkForKeyword('not', $value, $schema, $path, $i);
         $this->checkForKeyword('dependencies', $value, $schema, $path, $i);
+        $this->checkForKeyword('dependentSchemas', $value, $schema, $path, $i);
         $this->checkForKeyword('allOf', $value, $schema, $path, $i);
         $this->checkForKeyword('anyOf', $value, $schema, $path, $i);
         $this->checkForKeyword('oneOf', $value, $schema, $path, $i);

src/JsonSchema/Constraints/Drafts/Draft2019/Factory.php

@@ -14,6 +14,7 @@ class Factory extends \JsonSchema\Constraints\Factory
         'additionalProperties' => AdditionalPropertiesConstraint::class,
         'additionalItems' => AdditionalItemsConstraint::class,
         'dependencies' => DependenciesConstraint::class,
+        'dependentSchemas' => DependentSchemasConstraint::class,
         'type' => TypeConstraint::class,
         'const' => ConstConstraint::class,
         'enum' => EnumConstraint::class,