Added support for optional explicit BinarySuffix precision

Author: mostertb

src/Coduo/PHPHumanizer/Number.php

@@ -19,9 +19,9 @@ public static function ordinal($number)
         return (string) new Ordinal($number);
     }
 
-    public static function binarySuffix($number, $locale = 'en')
+    public static function binarySuffix($number, $locale = 'en', $precision = null)
     {
-        $binarySuffix = new BinarySuffix($number, $locale);
+        $binarySuffix = new BinarySuffix($number, $locale, $precision);
 
         return $binarySuffix->convert();
     }

src/Coduo/PHPHumanizer/String/BinarySuffix.php

@@ -29,21 +29,53 @@ class BinarySuffix
     );
 
     /**
-     * @param $number
-     * @param string $locale
+     * @param integer $number
+     * @param string  $locale
+     * @param integer $precision
      *
      * @throws \InvalidArgumentException
      */
-    public function __construct($number, $locale = 'en')
+    public function __construct($number, $locale = 'en', $precision = null)
     {
         if (!is_numeric($number)) {
             throw new \InvalidArgumentException('Binary suffix converter accept only numeric values.');
         }
 
+        if(!is_null($precision)){
+            $this->setSpecificPrecisionFormat($precision);
+        }
+
         $this->number = (int) $number;
         $this->locale = $locale;
     }
 
+    /**
+     * Replaces the default ICU 56.1 decimal formats defined in $binaryPrefixes with ones that provide the same symbols
+     * but the provided number of decimal places
+     *
+     * @param integer $precision
+     *
+     * @throws \InvalidArgumentException
+     */
+    protected function setSpecificPrecisionFormat($precision)
+    {
+        if($precision < 0){
+            throw new \InvalidArgumentException('Precision must be positive');
+        }
+        if($precision > 3){
+            throw new \InvalidArgumentException('Invalid precision. Binary suffix converter can only represent values in '.
+                'up to three decimal places');
+        }
+
+        $icuFormat = str_pad('#.', (2+$precision), '0');
+        foreach ($this->binaryPrefixes as $size => $unitPattern) {
+            if($size >= 1024){
+                $symbol = substr($unitPattern, strpos($unitPattern, ' '));
+                $this->binaryPrefixes[$size] = $icuFormat.$symbol;
+            }
+        }
+    }
+
     public function convert()
     {
         $formatter = new \NumberFormatter($this->locale, \NumberFormatter::PATTERN_DECIMAL);