[Types] Add JsonDecodeDynamicReturnTypeExtension

src/Type/Php/JsonDecodeDynamicReturnTypeExtension.php

@@ -0,0 +1,86 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Type\Php;
+
+use Nette\Utils\Json;
+use PhpParser\Node\Expr\FuncCall;
+use PHPStan\Analyser\Scope;
+use PHPStan\Reflection\FunctionReflection;
+use PHPStan\Type\ArrayType;
+use PHPStan\Type\BooleanType;
+use PHPStan\Type\Constant\ConstantStringType;
+use PHPStan\Type\ConstantTypeHelper;
+use PHPStan\Type\DynamicFunctionReturnTypeExtension;
+use PHPStan\Type\FloatType;
+use PHPStan\Type\IntegerType;
+use PHPStan\Type\MixedType;
+use PHPStan\Type\ObjectType;
+use PHPStan\Type\StringType;
+use PHPStan\Type\Type;
+use PHPStan\Type\UnionType;
+use stdClass;
+
+final class JsonDecodeDynamicReturnTypeExtension implements DynamicFunctionReturnTypeExtension
+{
+	public function isFunctionSupported(FunctionReflection $functionReflection): bool
+	{
+		// @todo - finds only "assertType", but not "json_decode" :/
+		dump($functionReflection->getName());
+
+		return $functionReflection->getName() === 'json_decode';
+	}
+
+	public function getTypeFromFunctionCall(FunctionReflection $functionReflection, FuncCall $funcCall, Scope $scope): Type
+	{
+		$args = $funcCall->getArgs();
+
+		dump('___');
+		die;
+
+		$isForceArray = $this->isForceArray($funcCall);
+
+		$firstArgValue = $args[0]->value;
+		$firstValueType = $scope->getType($firstArgValue);
+
+		if ($firstValueType instanceof ConstantStringType) {
+			$resolvedType = $this->resolveConstantStringType($firstValueType, $isForceArray);
+		} else {
+			$resolvedType = new MixedType();
+		}
+
+		if (! $resolvedType instanceof MixedType) {
+			return $resolvedType;
+		}
+
+		// fallback type
+		if ($isForceArray) {
+			return new UnionType([
+				new ArrayType(new MixedType(), new MixedType()),
+				new StringType(),
+				new FloatType(),
+				new IntegerType(),
+				new BooleanType(),
+			]);
+		}
+
+		// scalar types with stdClass
+		return new UnionType([
+			new ObjectType(stdClass::class),
+			new StringType(),
+			new FloatType(),
+			new IntegerType(),
+			new BooleanType(),
+		]);
+	}
+
+	private function resolveConstantStringType(ConstantStringType $constantStringType, bool $isForceArray): Type
+	{
+		if ($isForceArray) {
+			$decodedValue = Json::decode($constantStringType->getValue(), Json::FORCE_ARRAY);
+		} else {
+			$decodedValue = Json::decode($constantStringType->getValue());
+		}
+
+		return ConstantTypeHelper::getTypeFromValue($decodedValue);
+	}
+}

tests/Type/Nette/NetteUtilsJsonDecodeDynamicReturnTypeExtensionTest.php

@@ -35,7 +35,7 @@ public function testAsserts(string $assertType, string $file, ...$args): void
 	 */
 	public static function getAdditionalConfigFiles(): array
 	{
-		return [__DIR__ . '/config/json_decode_extension.neon'];
+		return [__DIR__ . '/config/nette_json_decode_extension.neon'];
 	}
 
 }

tests/Type/Php/JsonDecodeDynamicReturnTypeExtensionTest.php

@@ -0,0 +1,42 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PHPStan\Type\Php;
+
+use PHPStan\Testing\TypeInferenceTestCase;
+
+final class JsonDecodeDynamicReturnTypeExtensionTest extends TypeInferenceTestCase
+{
+
+	/**
+	 * @return iterable<mixed>
+	 */
+	public function dataAsserts(): iterable
+	{
+		yield from $this->gatherAssertTypes(__DIR__ . '/data/json_decode.php');
+		yield from $this->gatherAssertTypes(__DIR__ . '/data/json_decode_force_array.php');
+	}
+
+	/**
+	 * @dataProvider dataAsserts()
+	 * @param string $assertType
+	 * @param string $file
+	 * @param mixed ...$args
+	 */
+	public function testAsserts(string $assertType, string $file, ...$args): void
+	{
+		$this->assertFileAsserts($assertType, $file, ...$args);
+	}
+
+	/**
+	 * @return string[]
+	 */
+	public static function getAdditionalConfigFiles(): array
+	{
+		return [__DIR__ . '/config/json_decode_extension.neon'];
+	}
+
+
+
+}

tests/Type/Php/config/json_decode_extension.neon

@@ -0,0 +1,5 @@
+services:
+	-
+		class: PHPStan\Type\Php\JsonDecodeDynamicReturnTypeExtension
+		tags:
+			- phpstan.broker.dynamicFunctionReturnTypeExtension

tests/Type/Php/data/json_decode.php

@@ -0,0 +1,21 @@
+<?php
+
+use function PHPStan\Testing\assertType;
+
+$value = json_decode('true');
+assertType('true', $value);
+
+$value = json_decode('1');
+assertType('1', $value);
+
+$value = json_decode('1.5');
+assertType('1.5', $value);
+
+$value = json_decode('false');
+assertType('false', $value);
+
+$value = json_decode('{}');
+assertType('stdClass', $value);
+
+$value = json_decode('[1, 2, 3]');
+assertType('array{1, 2, 3}', $value);

tests/Type/Php/data/json_decode_force_array.php

@@ -0,0 +1,21 @@
+<?php
+
+use function PHPStan\Testing\assertType;
+
+$value = json_decode('true', true);
+assertType('true', $value);
+
+$value = json_decode('1', true);
+assertType('1', $value);
+
+$value = json_decode('1.5', true);
+assertType('1.5', $value);
+
+$value = json_decode('false', true);
+assertType('false', $value);
+
+$value = json_decode('{}', true);
+assertType('array{}', $value);
+
+$value = json_decode('[1, 2, 3]', true);
+assertType('array{1, 2, 3}', $value);