Create JsonSerializableStringifier

Author: henriquemoody

src/Stringifiers/JsonSerializableStringifier.php

@@ -0,0 +1,67 @@
+<?php
+
+/*
+ * This file is part of Respect/Stringifier.
+ *
+ * (c) Henrique Moody <[email protected]>
+ *
+ * For the full copyright and license information, please view the "LICENSE.md"
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace Respect\Stringifier\Stringifiers;
+
+use Respect\Stringifier\Quoter;
+use Respect\Stringifier\Stringifier;
+use JsonSerializable;
+
+/**
+ * Converts an instance of JsonSerializable into a string.
+ *
+ * @author Henrique Moody <[email protected]>
+ */
+final class JsonSerializableStringifier implements Stringifier
+{
+    /**
+     * @var Stringifier
+     */
+    private $stringifier;
+
+    /**
+     * @var Quoter
+     */
+    private $quoter;
+
+    /**
+     * Initializes the stringifier.
+     *
+     * @param Stringifier $stringifier
+     * @param Quoter $quoter
+     */
+    public function __construct(Stringifier $stringifier, Quoter $quoter)
+    {
+        $this->stringifier = $stringifier;
+        $this->quoter = $quoter;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function stringify($raw, int $depth): ?string
+    {
+        if (!$raw instanceof JsonSerializable) {
+            return null;
+        }
+
+        return $this->quoter->quote(
+            sprintf(
+                '[json-serializable] (%s: %s)',
+                get_class($raw),
+                $this->stringifier->stringify($raw->jsonSerialize(), $depth + 1)
+            ),
+            $depth
+        );
+    }
+}

tests/unit/Stringifiers/JsonSerializableStringifierTest.php

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+<?php
+
+/*
+ * This file is part of Respect/Stringifier.
+ *
+ * (c) Henrique Moody <[email protected]>
+ *
+ * For the full copyright and license information, please view the "LICENSE.md"
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace Respect\Stringifier\Test\Stringifiers;
+
+use JsonSerializable;
+use Respect\Stringifier\Quoter;
+use Respect\Stringifier\Stringifier;
+use Respect\Stringifier\Stringifiers\JsonSerializableStringifier;
+use PHPUnit\Framework\TestCase;
+use stdClass;
+
+/**
+ * @covers \Respect\Stringifier\Stringifiers\JsonSerializableStringifier
+ *
+ * @author Henrique Moody <[email protected]>
+ */
+final class JsonSerializableStringifierTest extends TestCase
+{
+    /**
+     * @test
+     */
+    public function shouldConvertToStringWhenRawValueIsAJsonSerializableObject(): void
+    {
+        $raw = new JsonSerializableObject();
+        $depth = 0;
+
+        $stringifiedData = '-stringified-';
+
+        $expectedValue = '[json-serializable] ('.JsonSerializableObject::class.': '.$stringifiedData.')';
+
+        $stringifierMock = $this->createMock(Stringifier::class);
+        $stringifierMock
+            ->expects($this->once())
+            ->method('stringify')
+            ->with(JsonSerializableObject::JSON_VALUE, $depth + 1)
+            ->willReturn($stringifiedData);
+
+        $quoterMock = $this->createMock(Quoter::class);
+        $quoterMock
+            ->expects($this->once())
+            ->method('quote')
+            ->with($expectedValue, $depth)
+            ->willReturn($expectedValue);
+
+        $jsonSerializableStringifier = new JsonSerializableStringifier($stringifierMock, $quoterMock);
+
+        self::assertSame($expectedValue, $jsonSerializableStringifier->stringify($raw, $depth));
+    }
+
+    /**
+     * @test
+     */
+    public function shouldNotConvertToStringWhenRawValueIsNotTraversable(): void
+    {
+        $raw = new stdClass();
+        $depth = 1;
+
+        $stringifierMock = $this->createMock(Stringifier::class);
+        $stringifierMock
+            ->expects($this->never())
+            ->method('stringify');
+
+        $quoterMock = $this->createMock(Quoter::class);
+        $quoterMock
+            ->expects($this->never())
+            ->method('quote');
+
+        $jsonSerializableStringifier = new JsonSerializableStringifier($stringifierMock, $quoterMock);
+
+        self::assertNull($jsonSerializableStringifier->stringify($raw, $depth));
+    }
+}
+
+final class JsonSerializableObject implements JsonSerializable
+{
+    public const JSON_VALUE = [1, true, 'foo', null];
+
+    public function jsonSerialize(): array
+    {
+        return self::JSON_VALUE;
+    }
+}