Added ability to map to backed enums

Author: Brammm

src/EnvMapper.php

@@ -76,11 +76,22 @@ public function map(string $class, bool $requireValues = false, ?array $source =
      * @return int|float|string|bool
      *   The passed value, but now with the correct type.
      */
-    private function typeNormalize(string $val, \ReflectionProperty $rProp): int|float|string|bool
+    private function typeNormalize(string $val, \ReflectionProperty $rProp): int|float|string|bool|\BackedEnum
     {
         $rType = $rProp->getType();
         if ($rType instanceof \ReflectionNamedType) {
-            return match ($rType->getName()) {
+            $name = $rType->getName();
+
+            if (is_a($name, \BackedEnum::class, true)) {
+                $rEnum = new \ReflectionEnum($name);
+                $backingType = $rEnum->getBackingType();
+                assert($backingType instanceof \ReflectionNamedType);
+                $isIntBacked = $backingType->getName() === 'int';
+
+                return $name::from($isIntBacked ? (int) $val : $val);
+            }
+
+            return match ($name) {
                 'string' => $val,
                 'float' => is_numeric($val)
                     ? (float) $val

tests/EnvMapperTest.php

@@ -7,7 +7,9 @@
 use Crell\EnvMapper\Envs\EnvWithDefaults;
 use Crell\EnvMapper\Envs\EnvWithMissingValue;
 use Crell\EnvMapper\Envs\EnvWithTypeMismatch;
+use Crell\EnvMapper\Envs\IntegerBackedEnum;
 use Crell\EnvMapper\Envs\SampleEnvironment;
+use Crell\EnvMapper\Envs\StringBackedEnum;
 use PHPUnit\Framework\Attributes\Test;
 use PHPUnit\Framework\TestCase;
 
@@ -22,6 +24,8 @@ class EnvMapperTest extends TestCase
         'SHLVL' => '1',
         'ZIP_CODE' => '01234',
         'BOOL' => '1',
+        'STRING_BACKED_ENUM' => 'FOO',
+        'INTEGER_BACKED_ENUM' => '2',
     ];
 
     #[Test]
@@ -39,6 +43,8 @@ public function mapping_different_types_with_defaults_parses_correctly(): void
         self::assertNotNull($env->shlvl);
         self::assertSame('01234', $env->zipCode);
         self::assertSame(true, $env->bool);
+        self::assertEquals(StringBackedEnum::Foo, $env->stringBackedEnum);
+        self::assertEquals(IntegerBackedEnum::Bar, $env->integerBackedEnum);
         self::assertEquals('default', $env->missing);
         self::assertEquals(false, $env->missingFalse);
         self::assertEquals('', $env->missingEmptyString);

tests/Envs/IntegerBackedEnum.php

@@ -0,0 +1,11 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Crell\EnvMapper\Envs;
+
+enum IntegerBackedEnum: int {
+    case Foo = 1;
+    case Bar = 2;
+    case Baz = 3;
+}

tests/Envs/SampleEnvironment.php

@@ -19,6 +19,9 @@ public function __construct(
         // This is a numeric string, but should stay a string.
         public readonly string $zipCode,
         public readonly bool $bool,
+        // These should be mapped using ::from()
+        public readonly StringBackedEnum $stringBackedEnum,
+        public readonly IntegerBackedEnum $integerBackedEnum,
         // This is not defined in the environment, so the default value should be used.
         public readonly string $missing = 'default',
         // These are not defined in the environment, so the default falsy values should be used.

tests/Envs/StringBackedEnum.php

@@ -0,0 +1,11 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Crell\EnvMapper\Envs;
+
+enum StringBackedEnum: string {
+    case Foo = 'FOO';
+    case Bar = 'BAR';
+    case Baz = 'BAZ';
+}