Enhancement: Implement NoParameterWithNullDefaultValueRule

.php_cs.fixture

@@ -3,6 +3,7 @@
 use Localheinz\PhpCsFixer\Config;
 
 $config = Config\Factory::fromRuleSet(new Config\RuleSet\Php71(''), [
+    'lowercase_constants' => false,
     'static_lambda' => false,
 ]);
 

CHANGELOG.md

@@ -16,6 +16,11 @@ For a full diff see [`0.2.0...master`](https://github.com/localheinz/phpstan-rul
   `Methods\NoNullableReturnTypeDeclarationRule`, which reports an error
   when a method declared on an anonymous class, a class, or an interface has a
   nullable return type declaration ([#16](https://github.com/localheinz/phpstan-rules/pull/16)), by [@localheinz](https://github.com/localheinz)
+* added `Functions\NoNullDefaultValueRule`, which reports an error when a
+  named function has a parameter with `null` as default value, and
+  `Methods\NoParameterWithNullDefaultValueRule`, which reports an error when a
+  method declared on an anonymous class, a class, or an interface has a
+  parameter with `null` as default value ([#26](https://github.com/localheinz/phpstan-rules/pull/26)), by [@localheinz](https://github.com/localheinz)
 
 ## [`0.2.0`](https://github.com/localheinz/phpstan-rules/releases/tag/0.2.0)
 

README.md

@@ -22,7 +22,9 @@ This package provides the following rules for use with [`phpstan/phpstan`](https
 * [`Localheinz\PHPStan\Rules\Classes\AbstractOrFinalRule`](https://github.com/localheinz/phpstan-rules#classesabstractorfinalrule)
 * [`Localheinz\PHPStan\Rules\Classes\FinalRule`](https://github.com/localheinz/phpstan-rules#classesfinalrule)
 * [`Localheinz\PHPStan\Rules\Functions\NoNullableReturnTypeDeclarationRule`](https://github.com/localheinz/phpstan-rules#functionsnonullablereturntypedeclarationrule)
+* [`Localheinz\PHPStan\Rules\Functions\NoParameterWithNullDefaultValueRule`](https://github.com/localheinz/phpstan-rules#functionsnoparameterwithnulldefaultvaluerule)
 * [`Localheinz\PHPStan\Rules\Methods\NoNullableReturnTypeDeclarationRule`](https://github.com/localheinz/phpstan-rules#methodsnonullablereturntypedeclarationrule)
+* [`Localheinz\PHPStan\Rules\Methods\NoParameterWithNullDefaultValueRule`](https://github.com/localheinz/phpstan-rules#methodsnoparameterwithnulldefaultvaluerule)
 
 ### `Classes\AbstractOrFinalRule`
 
@@ -85,6 +87,17 @@ rules:
 	- Localheinz\PHPStan\Rules\Functions\NoNullableReturnTypeDeclarationRule
 ```
 
+### `Functions\NoParameterWithNullDefaultValueRule`
+
+This rule reports an error when a named function has a parameter with `null` as default value.
+
+If you want to use this rule, add it to your `phpstan.neon`:
+
+```neon
+rules:
+	- Localheinz\PHPStan\Rules\Functions\NoParameterWithNullDefaultValueRule
+```
+
 ### `Methods\NoNullableReturnTypeDeclarationRule`
 
 This rule reports an error when a method declared on an anonymous class, a class, or an interface uses a nullable return type declaration.
@@ -96,6 +109,17 @@ rules:
 	- Localheinz\PHPStan\Rules\Methods\NoNullableReturnTypeDeclarationRule
 ```
 
+### `Methods\NoParameterWithNullDefaultValueRule`
+
+This rule reports an error when a method declared on an anonymous class, a class, or an interface has a parameter with `null` as default value.
+
+If you want to use this rule, add it to your `phpstan.neon`:
+
+```neon
+rules:
+	- Localheinz\PHPStan\Rules\Methods\NoParameterWithNullDefaultValueRule
+```
+
 ## Changelog
 
 Please have a look at [`CHANGELOG.md`](CHANGELOG.md).

phpstan.neon

@@ -4,4 +4,6 @@ includes:
 rules:
 	- Localheinz\PHPStan\Rules\Classes\AbstractOrFinalRule
 	- Localheinz\PHPStan\Rules\Functions\NoNullableReturnTypeDeclarationRule
+	- Localheinz\PHPStan\Rules\Functions\NoParameterWithNullDefaultValueRule
 	- Localheinz\PHPStan\Rules\Methods\NoNullableReturnTypeDeclarationRule
+	- Localheinz\PHPStan\Rules\Methods\NoParameterWithNullDefaultValueRule

src/Functions/NoParameterWithNullDefaultValueRule.php

@@ -0,0 +1,67 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * Copyright (c) 2018 Andreas Möller.
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ *
+ * @see https://github.com/localheinz/phpstan-rules
+ */
+
+namespace Localheinz\PHPStan\Rules\Functions;
+
+use PhpParser\Node;
+use PHPStan\Analyser\Scope;
+use PHPStan\Rules\Rule;
+
+final class NoParameterWithNullDefaultValueRule implements Rule
+{
+    public function getNodeType(): string
+    {
+        return Node\Stmt\Function_::class;
+    }
+
+    /**
+     * @param Node\Stmt\Function_ $node
+     * @param Scope               $scope
+     *
+     * @return array
+     */
+    public function processNode(Node $node, Scope $scope): array
+    {
+        if (0 === \count($node->params)) {
+            return [];
+        }
+
+        $params = \array_filter($node->params, static function (Node\Param $node): bool {
+            if (!$node->default instanceof Node\Expr\ConstFetch) {
+                return false;
+            }
+
+            return 'null' === $node->default->name->toLowerString();
+        });
+
+        if (0 === \count($params)) {
+            return [];
+        }
+
+        $functionName = $node->namespacedName;
+
+        return \array_map(static function (Node\Param $node) use ($functionName): string {
+            /** @var Node\Expr\Variable $variable */
+            $variable = $node->var;
+
+            /** @var string $parameterName */
+            $parameterName = $variable->name;
+
+            return \sprintf(
+                'Parameter "$%s" of function "%s()" should not have null as default value.',
+                $parameterName,
+                $functionName
+            );
+        }, $params);
+    }
+}

src/Methods/NoParameterWithNullDefaultValueRule.php

@@ -0,0 +1,90 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * Copyright (c) 2018 Andreas Möller.
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ *
+ * @see https://github.com/localheinz/phpstan-rules
+ */
+
+namespace Localheinz\PHPStan\Rules\Methods;
+
+use PhpParser\Node;
+use PHPStan\Analyser\Scope;
+use PHPStan\Reflection;
+use PHPStan\Rules\Rule;
+
+final class NoParameterWithNullDefaultValueRule implements Rule
+{
+    public function getNodeType(): string
+    {
+        return Node\Stmt\ClassMethod::class;
+    }
+
+    /**
+     * @param Node\Stmt\ClassMethod $node
+     * @param Scope                 $scope
+     *
+     * @return array
+     */
+    public function processNode(Node $node, Scope $scope): array
+    {
+        if (0 === \count($node->params)) {
+            return [];
+        }
+
+        $params = \array_filter($node->params, static function (Node\Param $node): bool {
+            if (!$node->default instanceof Node\Expr\ConstFetch) {
+                return false;
+            }
+
+            return 'null' === $node->default->name->toLowerString();
+        });
+
+        if (0 === \count($params)) {
+            return [];
+        }
+
+        $methodName = $node->name->toString();
+
+        /** @var Reflection\ClassReflection $classReflection */
+        $classReflection = $scope->getClassReflection();
+
+        if ($classReflection->isAnonymous()) {
+            return \array_map(static function (Node\Param $node) use ($methodName): string {
+                /** @var Node\Expr\Variable $variable */
+                $variable = $node->var;
+
+                /** @var string $parameterName */
+                $parameterName = $variable->name;
+
+                return \sprintf(
+                    'Parameter "$%s" of method "%s()" in anonymous class should not have null as default value.',
+                    $parameterName,
+                    $methodName
+                );
+            }, $params);
+        }
+
+        $className = $classReflection->getName();
+
+        return \array_map(static function (Node\Param $node) use ($className, $methodName): string {
+            /** @var Node\Expr\Variable $variable */
+            $variable = $node->var;
+
+            /** @var string $parameterName */
+            $parameterName = $variable->name;
+
+            return \sprintf(
+                'Parameter "$%s" of method "%s::%s()" should not have null as default value.',
+                $parameterName,
+                $className,
+                $methodName
+            );
+        }, $params);
+    }
+}

test/Fixture/Functions/NoParameterWithNullDefaultValueRule/Failure/named-function-with-parameter-with-null-default-value.php

@@ -0,0 +1,10 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Localheinz\PHPStan\Rules\Test\Fixture\Functions\NoParameterWithNullDefaultValueRule\Failure;
+
+function foo($bar = null)
+{
+    return $bar;
+}

test/Fixture/Functions/NoParameterWithNullDefaultValueRule/Failure/named-function-with-parameter-with-root-namespace-referenced-null-default-value.php

@@ -0,0 +1,10 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Localheinz\PHPStan\Rules\Test\Fixture\Functions\NoParameterWithNullDefaultValueRule\Failure;
+
+function foo($bar = \null)
+{
+    return $bar;
+}

test/Fixture/Functions/NoParameterWithNullDefaultValueRule/Failure/named-function-with-parameter-with-wrongly-capitalized-null-default-value.php

@@ -0,0 +1,10 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Localheinz\PHPStan\Rules\Test\Fixture\Functions\NoParameterWithNullDefaultValueRule\Failure;
+
+function foo($bar = nUlL)
+{
+    return $bar;
+}

test/Fixture/Functions/NoParameterWithNullDefaultValueRule/Success/anonymous-function-with-parameter-with-non-null-default-value.php

@@ -0,0 +1,9 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Localheinz\PHPStan\Rules\Test\Fixture\Functions\NoParameterWithNullDefaultValueRule\Success;
+
+$foo = function ($bar = true) {
+    return $bar;
+};

test/Fixture/Functions/NoParameterWithNullDefaultValueRule/Success/anonymous-function-with-parameter-with-null-default-value.php

@@ -0,0 +1,9 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Localheinz\PHPStan\Rules\Test\Fixture\Functions\NoParameterWithNullDefaultValueRule\Success;
+
+$foo = function ($bar = null) {
+    return $bar;
+};

test/Fixture/Functions/NoParameterWithNullDefaultValueRule/Success/anonymous-function-with-parameter-with-root-namespace-referenced-null-default-value.php

@@ -0,0 +1,9 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Localheinz\PHPStan\Rules\Test\Fixture\Functions\NoParameterWithNullDefaultValueRule\Success;
+
+$foo = function ($bar = null) {
+    return $bar;
+};

test/Fixture/Functions/NoParameterWithNullDefaultValueRule/Success/anonymous-function-with-parameter-with-wrongly-capitalized-null-default-value.php

@@ -0,0 +1,9 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Localheinz\PHPStan\Rules\Test\Fixture\Functions\NoParameterWithNullDefaultValueRule\Success;
+
+$foo = function ($bar = null) {
+    return $bar;
+};

test/Fixture/Functions/NoParameterWithNullDefaultValueRule/Success/anonymous-function-with-parameter-without-default-value.php

@@ -0,0 +1,9 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Localheinz\PHPStan\Rules\Test\Fixture\Functions\NoParameterWithNullDefaultValueRule\Success;
+
+$foo = function ($bar) {
+    return $bar;
+};

test/Fixture/Functions/NoParameterWithNullDefaultValueRule/Success/anonymous-function-without-parameters.php

@@ -0,0 +1,8 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Localheinz\PHPStan\Rules\Test\Fixture\Functions\NoParameterWithNullDefaultValueRule\Success;
+
+$foo = function () {
+};

test/Fixture/Functions/NoParameterWithNullDefaultValueRule/Success/named-function-with-parameter-with-non-null-default-value.php

@@ -0,0 +1,10 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Localheinz\PHPStan\Rules\Test\Fixture\Functions\NoParameterWithNullDefaultValueRule\Success;
+
+function foo($bar = true)
+{
+    return $bar;
+}

test/Fixture/Functions/NoParameterWithNullDefaultValueRule/Success/named-function-with-parameter-without-default-value.php

@@ -0,0 +1,10 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Localheinz\PHPStan\Rules\Test\Fixture\Functions\NoParameterWithNullDefaultValueRule\Success;
+
+function foo($bar)
+{
+    return $bar;
+}

test/Fixture/Functions/NoParameterWithNullDefaultValueRule/Success/named-function-without-parameters.php

@@ -0,0 +1,9 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Localheinz\PHPStan\Rules\Test\Fixture\Functions\NoParameterWithNullDefaultValueRule\Success;
+
+function foo()
+{
+}

test/Fixture/Methods/NoParameterWithNullDefaultValueRule/Failure/MethodInClassWithParameterWithNullDefaultValue.php

@@ -0,0 +1,13 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Localheinz\PHPStan\Rules\Test\Fixture\Methods\NoParameterWithNullDefaultValueRule\Failure;
+
+final class MethodInClassWithParameterWithNullDefaultValue
+{
+    public function foo($bar = null)
+    {
+        return $bar;
+    }
+}

test/Fixture/Methods/NoParameterWithNullDefaultValueRule/Failure/MethodInClassWithParameterWithRootNamespaceReferencedNullDefaultValue.php

@@ -0,0 +1,13 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Localheinz\PHPStan\Rules\Test\Fixture\Methods\NoParameterWithNullDefaultValueRule\Failure;
+
+final class MethodInClassWithParameterWithRootNamespaceReferencedNullDefaultValue
+{
+    public function foo($bar = \null)
+    {
+        return $bar;
+    }
+}

test/Fixture/Methods/NoParameterWithNullDefaultValueRule/Failure/MethodInClassWithParameterWithWronglyCapitalizedNullDefaultValue.php

@@ -0,0 +1,13 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Localheinz\PHPStan\Rules\Test\Fixture\Methods\NoParameterWithNullDefaultValueRule\Failure;
+
+final class MethodInClassWithParameterWithWronglyCapitalizedNullDefaultValue
+{
+    public function foo($bar = NuLl)
+    {
+        return $bar;
+    }
+}