[Validator] Update Type constraint, add number, finite-float and finite-number validations

[guillaume-a]

Q	A
Branch?	6.4
Bug fix?	no
New feature?	yes
Deprecations?	no
Tickets	Fix #50782
License	MIT
Doc PR	symfony/symfony-docs#18527

Contraint Type(['float']) can produce positives with INF or NAN.
This new types car narrow validation and limit validation to finite numbers.

#[Assert\Type(['int', 'finite-float'])]
private $value;

Thank you for helping me with this one.

[stof]

This is missing tests

[fabpot]

@guillaume-a Can you fix fabbot errors?

[derrabus]

Contraint Type(['float']) can produce false positives.

No, actually that constraint works as advertised because NaN and infinity are valid float values.

We should change the PR description.

[derrabus]

What happens if that validator encounters…

• … a non-numeric string?
• … null or an empty string?
• … something completely different lika an array or object?

Can we cover those scenarios with tests?

[guillaume-a]

Fixed fabbot errors.
Check against is_numeric() in the validator (in case of string, array, object $value)
Added tests scenarios for all thoses last checks.

null was allready checked (considered as valid)
empty is now checked and considered as invalid

[nicolas-grekas]

What about adding new types to the Type constraint instead?

#[Assert\Type(['finite-float'])]
#[Assert\Type(['number'])] # this would be (is_int || is_float) && is_finite

[guillaume-a]

Renamed Finite to IsFinite to match existing validators IsTrue IsNull ...

@nicolas-grekas originally I looked that way, but IMO it will add lots of complexity to Type validator since $types are considered in a global 'OR' condition. And we should then check againts is_finite() only in some cases only which may be hard to deterime.

But i'm open to discussion.

[nicolas-grekas]

It looks like this would be enough to support my proposal. Not too much complexity IMHO.

--- a/src/Symfony/Component/Validator/Constraints/TypeValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/TypeValidator.php
@@ -26,9 +26,11 @@ class TypeValidator extends ConstraintValidator
         'int' => 'is_int',
         'integer' => 'is_int',
         'long' => 'is_int',
+        'finite-float' => 'is_float && is_finite',
         'float' => 'is_float',
         'double' => 'is_float',
         'real' => 'is_float',
+        'number' => 'is_int || is_float && is_finite',
         'numeric' => 'is_numeric',
         'string' => 'is_string',
         'scalar' => 'is_scalar',
@@ -69,7 +71,13 @@ class TypeValidator extends ConstraintValidator
 
         foreach ($types as $type) {
             $type = strtolower($type);
-            if (isset(self::VALIDATION_FUNCTIONS[$type]) && self::VALIDATION_FUNCTIONS[$type]($value)) {
+            if (isset(self::VALIDATION_FUNCTIONS[$type]) && match (self::VALIDATION_FUNCTIONS[$type]) {
+                'finite-float' => \is_float($value) && \is_finite($value),
+                'number' => \is_int($value) || \is_float($value) && \is_finite($value),
+                default => self::VALIDATION_FUNCTIONS[$type]($value),
+            }) {
                 return;
             }

[guillaume-a]

Can someone explain me why we must write \is_float but we must write is_nan or is_finite without ?
What are the exact rules ?

[nicolas-grekas]

@guillaume-a check PHP-CS-Fixer/PHP-CS-Fixer#3048

[nicolas-grekas]

(can you have a look at the test failure?)

[guillaume-a]

(can you have a look at the test failure?)

Done. (And rebased too.)

[fabpot]

Thank you @guillaume-a.