includes/libs/ParamValidator/TypeDef/FloatDef.php

   1 <?php
   2
   3 namespace Wikimedia\ParamValidator\TypeDef;
   4
   5 use Wikimedia\ParamValidator\TypeDef;
   6 use Wikimedia\ParamValidator\ValidationException;
   7
   8 /**
   9  * Type definition for a floating-point type
  10  *
  11  * A valid representation consists of:
  12  *  - an optional sign (`+` or `-`)
  13  *  - a decimal number, using `.` as the decimal separator and no grouping
  14  *  - an optional E-notation suffix: the letter 'e' or 'E', an optional
  15  *    sign, and an integer
  16  *
  17  * Thus, for example, "12", "-.4", "6.022e23", or "+1.7e-10".
  18  *
  19  * The result from validate() is a PHP float.
  20  *
  21  * ValidationException codes:
  22  *  - 'badfloat': The value was invalid. No data.
  23  *  - 'notfinite': The value was in a valid format, but conversion resulted in
  24  *    infinity or NAN.
  25  *
  26  * @since 1.34
  27  */
  28 class FloatDef extends TypeDef {
  29
  30         public function validate( $name, $value, array $settings, array $options ) {
  31                 // Use a regex so as to avoid any potential oddness PHP's default conversion might allow.
  32                 if ( !preg_match( '/^[+-]?(?:\d*\.)?\d+(?:[eE][+-]?\d+)?$/D', $value ) ) {
  33                         throw new ValidationException( $name, $value, $settings, 'badfloat', [] );
  34                 }
  35
  36                 $ret = (float)$value;
  37                 if ( !is_finite( $ret ) ) {
  38                         throw new ValidationException( $name, $value, $settings, 'notfinite', [] );
  39                 }
  40
  41                 return $ret;
  42         }
  43
  44         /**
  45          * Attempt to fix locale weirdness
  46          *
  47          * We don't have any usable number formatting function that's not locale-aware,
  48          * and `setlocale()` isn't safe in multithreaded environments. Sigh.
  49          *
  50          * @param string $value Value to fix
  51          * @return string
  52          */
  53         private function fixLocaleWeirdness( $value ) {
  54                 $localeData = localeconv();
  55                 if ( $localeData['decimal_point'] !== '.' ) {
  56                         $value = strtr( $value, [
  57                                 $localeData['decimal_point'] => '.',
  58                                 // PHP's number formatting currently uses only the first byte from 'decimal_point'.
  59                                 // See upstream bug https://bugs.php.net/bug.php?id=78113
  60                                 $localeData['decimal_point'][0] => '.',
  61                         ] );
  62                 }
  63                 return $value;
  64         }
  65
  66         public function stringifyValue( $name, $value, array $settings, array $options ) {
  67                 // Ensure sufficient precision for round-tripping. PHP_FLOAT_DIG was added in PHP 7.2.
  68                 $digits = defined( 'PHP_FLOAT_DIG' ) ? PHP_FLOAT_DIG : 15;
  69                 return $this->fixLocaleWeirdness( sprintf( "%.{$digits}g", $value ) );
  70         }
  71
  72 }