minor #14228 Add PHP7 compatible versions for the Null/True/False constraints as they are reserved words in PHP7 (stefan.r)

This PR was merged into the 2.3 branch.

Discussion
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Add PHP7 compatible versions for the Null/True/False constraints as they are reserved words in PHP7

| Q             | A
| ------------- | ---
| Bug fix?      |  PHP7 compatibility
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | N/A
| Fixed tickets | N/A - helps towards symfony/symfony#14086
| License       | MIT

Null, True and False are reserved words in PHP7:

https://wiki.php.net/rfc/reserve_more_types_in_php_7

Commits
-------

44edbdf Fixed compatibility with PHP7 and up by introducing new constraints (IsNull, IsTrue, IsFalse) and related validators (IsNullValidator, IsTrueValidator, IsFalseValidator)

Author: stof

Extension/Validator/ValidatorTypeGuesser.php

@@ -157,6 +157,8 @@ public function guessTypeForConstraint(Constraint $constraint)
 
             case 'Symfony\Component\Validator\Constraints\True':
             case 'Symfony\Component\Validator\Constraints\False':
+            case 'Symfony\Component\Validator\Constraints\IsTrue':
+            case 'Symfony\Component\Validator\Constraints\IsFalse':
                 return new TypeGuess('checkbox', array(), Guess::MEDIUM_CONFIDENCE);
         }
     }
@@ -174,6 +176,7 @@ public function guessRequiredForConstraint(Constraint $constraint)
             case 'Symfony\Component\Validator\Constraints\NotNull':
             case 'Symfony\Component\Validator\Constraints\NotBlank':
             case 'Symfony\Component\Validator\Constraints\True':
+            case 'Symfony\Component\Validator\Constraints\IsTrue':
                 return new ValueGuess(true, Guess::HIGH_CONFIDENCE);
         }
     }

Tests/Extension/Validator/ValidatorTypeGuesserTest.php

@@ -19,7 +19,7 @@
 use Symfony\Component\Validator\Constraints\NotBlank;
 use Symfony\Component\Validator\Constraints\NotNull;
 use Symfony\Component\Validator\Constraints\Range;
-use Symfony\Component\Validator\Constraints\True;
+use Symfony\Component\Validator\Constraints\IsTrue;
 use Symfony\Component\Validator\Constraints\Type;
 use Symfony\Component\Validator\Mapping\ClassMetadata;
 
@@ -64,7 +64,7 @@ public function guessRequiredProvider()
         return array(
             array(new NotNull(), new ValueGuess(true, Guess::HIGH_CONFIDENCE)),
             array(new NotBlank(), new ValueGuess(true, Guess::HIGH_CONFIDENCE)),
-            array(new True(), new ValueGuess(true, Guess::HIGH_CONFIDENCE)),
+            array(new IsTrue(), new ValueGuess(true, Guess::HIGH_CONFIDENCE)),
             array(new Length(10), new ValueGuess(false, Guess::LOW_CONFIDENCE)),
             array(new Range(array('min' => 1, 'max' => 20)), new ValueGuess(false, Guess::LOW_CONFIDENCE)),
         );
@@ -84,6 +84,18 @@ public function testGuessRequired($constraint, $guess)
         $this->assertEquals($guess, $this->guesser->guessRequired(self::TEST_CLASS, self::TEST_PROPERTY));
     }
 
+    /**
+     * @group legacy
+     */
+    public function testLegacyGuessRequired()
+    {
+        if (PHP_VERSION_ID >= 70000) {
+            $this->markTestSkipped('Cannot use a class called True on PHP 7 or higher.');
+        }
+        $true = 'Symfony\Component\Validator\Constraints\True';
+        $this->testGuessRequired(new $true(), new ValueGuess(true, Guess::HIGH_CONFIDENCE));
+    }
+
     public function testGuessRequiredReturnsFalseForUnmappedProperties()
     {
         $this->assertEquals(new ValueGuess(false, Guess::LOW_CONFIDENCE), $this->guesser->guessRequired(self::TEST_CLASS, self::TEST_PROPERTY));

composer.json

@@ -25,7 +25,7 @@
     "require-dev": {
         "symfony/phpunit-bridge": "~2.7",
         "doctrine/collections": "~1.0",
-        "symfony/validator": "~2.3.0,>=2.3.20",
+        "symfony/validator": "~2.3.29",
         "symfony/translation": "~2.0,>=2.0.5",
         "symfony/http-foundation": "~2.2"
     },