Add callable validator rule #22

CHANGELOG.md

@@ -7,7 +7,7 @@ All notable changes to this project will be documented in this file, in reverse
 
 ### Added
 
-- Nothing.
+- [#22](https://github.com/elie29/validator/issues/22) Add callable validator rule.
 
 ### Changed
 

README.md

@@ -58,6 +58,7 @@ $validator->validate(); // bool depends on $_POST content
 1. [ArrayRule](https://github.com/elie29/validator/blob/master/src/Rule/ArrayRule.php) accepts `min` and `max` options. Empty value is cast to empty array [].
 1. [BicRule](https://github.com/elie29/validator/blob/master/src/Rule/BicRule.php)
 1. [BooleanRule](https://github.com/elie29/validator/blob/master/src/Rule/BooleanRule.php) accepts `cast` option.
+1. [CallableRule](https://github.com/elie29/validator/blob/master/src/Rule/CallableRule.php) accepts `callable` function.
 1. [ChoicesRule](https://github.com/elie29/validator/blob/master/src/Rule/ChoicesRule.php) accepts `list` option.
 1. [CompareRule](https://github.com/elie29/validator/blob/master/src/Rule/CompareRule.php) accepts `sign` and `expected` options. `sign` is [CompareRule::EQ](https://github.com/elie29/validator/blob/master/src/Rule/CompareConstants.php) by default, `expected` is null by default.
 1. [DateRule](https://github.com/elie29/validator/blob/master/src/Rule/DateRule.php) accepts `format` and `separator` options.

src/Rule/CallableRule.php

@@ -0,0 +1,64 @@
+<?php
+
+declare(strict_types = 1);
+
+namespace Elie\Validator\Rule;
+
+/**
+ * This class verifies that a value through a callable function.
+ */
+class CallableRule extends AbstractRule
+{
+
+    /**
+     * Specific message error code
+     */
+    public const INVALID_CALLABLE_CHECK = 'invalidCallableCheck';
+
+    /**
+     * Specific option for CallableRule
+     */
+    public const CALLABLE = 'callable';
+
+    /**
+     * @var callable _invoke|function($key, $value): bool
+     */
+    protected $callable;
+
+    /**
+     * Params could have the following structure:
+     * [
+     *   'required' => {bool:optional:false by default},
+     *   'trim' => {bool:optional:true by default:only if value is string},
+     *   'messages' => {array:optional:key/value message patterns},
+     *   'callable' => {callable:required:should receive key/value and return boolean}
+     * ]
+     */
+    public function __construct(string $key, $value, array $params = [])
+    {
+        parent::__construct($key, $value, $params);
+
+        $this->callable = $params[self::CALLABLE];
+
+        $this->messages = $this->messages + [
+            self::INVALID_CALLABLE_CHECK => '%key%: %value% did not pass the callable check',
+        ];
+    }
+
+    public function validate(): int
+    {
+        $run = parent::validate();
+
+        if ($run !== $this::CHECK) {
+            return $run;
+        }
+
+        $callable = $this->callable;
+
+        if (! $callable($this->key, $this->value)) {
+            return $this->setAndReturnError($this::INVALID_CALLABLE_CHECK);
+        }
+
+        return $this::VALID;
+    }
+}

tests/Rule/CallableRuleTest.php

@@ -0,0 +1,46 @@
+<?php
+
+declare(strict_types = 1);
+
+namespace Elie\Validator\Rule;
+
+use PHPUnit\Framework\TestCase;
+
+class CallableRuleTest extends TestCase
+{
+
+    /**
+     * @dataProvider getCallableRuleValueProvider
+     */
+    public function testValidate($value, array $params, int $expectedResult, string $expectedError): void
+    {
+        $rule = new CallableRule('name', $value, $params);
+
+        $res = $rule->validate();
+
+        assertThat($res, identicalTo($expectedResult));
+
+        assertThat($rule->getError(), identicalTo($expectedError));
+    }
+
+    public function getCallableRuleValueProvider(): \Generator
+    {
+        yield 'Given value could be empty when not required' => [
+            null, [CallableRule::CALLABLE => function ($key, $value): bool {
+                return $value === '102';
+            }], CallableRule::VALID, ''
+        ];
+
+        yield 'Given value should be validated through a callable' => [
+            '102', [CallableRule::CALLABLE => function ($key, $value): bool {
+                return $value === '102';
+            }], CallableRule::VALID, ''
+        ];
+
+        yield 'Given value should not be validated through a callable' => [
+            false, [CallableRule::CALLABLE => function ($key, $value): bool {
+                return $value === null;
+            }], CallableRule::ERROR, 'name: <FALSE> did not pass the callable check'
+        ];
+    }
+}