feat(mapper): json file to object mapper (#748)

Author: brendt

src/Tempest/Mapper/src/Mappers/JsonFileToObjectMapper.php

@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tempest\Mapper\Mappers;
+
+use function Tempest\map;
+use Tempest\Mapper\Mapper;
+use function Tempest\path;
+
+final readonly class JsonFileToObjectMapper implements Mapper
+{
+    public function canMap(mixed $from, mixed $to): bool
+    {
+        if (! is_string($from)) {
+            return false;
+        }
+
+        $path = path($from);
+
+        return $path->exists() && $path->extension() === 'json';
+    }
+
+    public function map(mixed $from, mixed $to): array
+    {
+        return map(json_decode(file_get_contents($from), associative: true))->collection()->to($to);
+    }
+}

tests/Integration/Mapper/Fixtures/objects.json

@@ -0,0 +1,10 @@
+[
+    {
+        "a": "a",
+        "b": "b"
+    },
+    {
+        "a": "c",
+        "b": "d"
+    }
+]

tests/Integration/Mapper/Mappers/JsonFileToObjectMapperTest.php

@@ -0,0 +1,26 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tests\Tempest\Integration\Mapper\Mappers;
+
+use function Tempest\map;
+use Tests\Tempest\Integration\FrameworkIntegrationTestCase;
+use Tests\Tempest\Integration\Mapper\Fixtures\ObjectA;
+
+/**
+ * @internal
+ */
+final class JsonFileToObjectMapperTest extends FrameworkIntegrationTestCase
+{
+    public function test_mapper(): void
+    {
+        $objects = map(__DIR__ . '/../Fixtures/objects.json')->collection()->to(ObjectA::class);
+
+        $this->assertCount(2, $objects);
+        $this->assertSame('a', $objects[0]->a);
+        $this->assertSame('b', $objects[0]->b);
+        $this->assertSame('c', $objects[1]->a);
+        $this->assertSame('d', $objects[1]->b);
+    }
+}