Move rounding code from Calculator to BigDecimal

brick · Jun 12, 2015 · 5533b2a · 5533b2a
1 parent cc30889
commit 5533b2a
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Showing 2 changed files with 67 additions and 85 deletions.
diff --git a/src/BigDecimal.php b/src/BigDecimal.php
@@ -264,6 +264,9 @@ public function multipliedBy($that)
      * @param int|null                 $scale        The desired scale, or null to use the scale of this number.
      *
      * @return BigDecimal
+     *
+     * @throws ArithmeticException       If RoundingMode::UNNECESSARY is provided and rounding was necessary.
+     * @throws \InvalidArgumentException If any of the arguments is not valid.
      */
     public function dividedBy($that, $roundingMode = RoundingMode::UNNECESSARY, $scale = null)
     {
@@ -291,10 +294,71 @@ public function dividedBy($that, $roundingMode = RoundingMode::UNNECESSARY, $sca
         $q = $that->valueWithMinScale($this->scale - $scale);
 
         $calculator = Calculator::get();
-        $result = $calculator->divRounded($p, $q, $roundingMode);
 
-        if ($result === null) {
-            throw ArithmeticException::roundingNecessary();
+        list ($result, $remainder) = $calculator->div($p, $q);
+
+        $hasDiscardedFraction = ($remainder !== '0');
+        $isPositiveOrZero = ($p[0] === '-') === ($q[0] === '-');
+
+        $discardedFractionSign = function() use ($calculator, $remainder, $q) {
+            $r = $calculator->abs($calculator->mul($remainder, '2'));
+            $q = $calculator->abs($q);
+
+            return $calculator->cmp($r, $q);
+        };
+
+        $increment = false;
+
+        switch ($roundingMode) {
+            case RoundingMode::UNNECESSARY:
+                if ($hasDiscardedFraction) {
+                    throw ArithmeticException::roundingNecessary();
+                }
+                break;
+
+            case RoundingMode::UP:
+                $increment = $hasDiscardedFraction;
+                break;
+
+            case RoundingMode::DOWN:
+                break;
+
+            case RoundingMode::CEILING:
+                $increment = $hasDiscardedFraction && $isPositiveOrZero;
+                break;
+
+            case RoundingMode::FLOOR:
+                $increment = $hasDiscardedFraction && ! $isPositiveOrZero;
+                break;
+
+            case RoundingMode::HALF_UP:
+                $increment = $discardedFractionSign() >= 0;
+                break;
+
+            case RoundingMode::HALF_DOWN:
+                $increment = $discardedFractionSign() > 0;
+                break;
+
+            case RoundingMode::HALF_CEILING:
+                $increment = $isPositiveOrZero ? $discardedFractionSign() >= 0 : $discardedFractionSign() > 0;
+                break;
+
+            case RoundingMode::HALF_FLOOR:
+                $increment = $isPositiveOrZero ? $discardedFractionSign() > 0 : $discardedFractionSign() >= 0;
+                break;
+
+            case RoundingMode::HALF_EVEN:
+                $lastDigit = (int) substr($result, -1);
+                $lastDigitIsEven = ($lastDigit % 2 === 0);
+                $increment = $lastDigitIsEven ? $discardedFractionSign() > 0 : $discardedFractionSign() >= 0;
+                break;
+
+            default:
+                throw new \InvalidArgumentException('Invalid rounding mode.');
+        }
+
+        if ($increment) {
+            $result = $calculator->add($result, $isPositiveOrZero ? '1' : '-1');
         }
 
         return new BigDecimal($result, $scale);

diff --git a/src/Internal/Calculator.php b/src/Internal/Calculator.php
@@ -144,88 +144,6 @@ public function cmp($a, $b)
         return $this->sign($this->sub($a, $b));
     }
 
-    /**
-     * Divides and rounds numbers.
-     *
-     * @param string  $p            The dividend.
-     * @param string  $q            The divisor, must not be zero.
-     * @param integer $roundingMode The rounding mode.
-     *
-     * @return string|null The divided and rounded number, or null if rounding was necessary.
-     *
-     * @throws \InvalidArgumentException If the rounding mode is invalid.
-     */
-    public function divRounded($p, $q, $roundingMode)
-    {
-        list ($result, $remainder) = $this->div($p, $q);
-
-        $hasDiscardedFraction = ($remainder !== '0');
-        $isPositiveOrZero = ($p[0] === '-') === ($q[0] === '-');
-
-        $discardedFractionSign = function() use ($remainder, $q) {
-            $r = $this->abs($this->mul($remainder, '2'));
-            $q = $this->abs($q);
-
-            return $this->cmp($r, $q);
-        };
-
-        $increment = false;
-
-        switch ($roundingMode) {
-            case RoundingMode::UNNECESSARY:
-                if ($hasDiscardedFraction) {
-                    return null;
-                }
-                break;
-
-            case RoundingMode::UP:
-                $increment = $hasDiscardedFraction;
-                break;
-
-            case RoundingMode::DOWN:
-                break;
-
-            case RoundingMode::CEILING:
-                $increment = $hasDiscardedFraction && $isPositiveOrZero;
-                break;
-
-            case RoundingMode::FLOOR:
-                $increment = $hasDiscardedFraction && ! $isPositiveOrZero;
-                break;
-
-            case RoundingMode::HALF_UP:
-                $increment = $discardedFractionSign() >= 0;
-                break;
-
-            case RoundingMode::HALF_DOWN:
-                $increment = $discardedFractionSign() > 0;
-                break;
-
-            case RoundingMode::HALF_CEILING:
-                $increment = $isPositiveOrZero ? $discardedFractionSign() >= 0 : $discardedFractionSign() > 0;
-                break;
-
-            case RoundingMode::HALF_FLOOR:
-                $increment = $isPositiveOrZero ? $discardedFractionSign() > 0 : $discardedFractionSign() >= 0;
-                break;
-
-            case RoundingMode::HALF_EVEN:
-                $lastDigit = (int) substr($result, -1);
-                $lastDigitIsEven = ($lastDigit % 2 === 0);
-                $increment = $lastDigitIsEven ? $discardedFractionSign() > 0 : $discardedFractionSign() >= 0;
-                break;
-
-            default:
-                throw new \InvalidArgumentException('Invalid rounding mode.');
-        }
-
-        if ($increment) {
-            $result = $this->add($result, $isPositiveOrZero ? '1' : '-1');
-        }
-
-        return $result;
-    }
-
     /**
      * Adds two numbers.
      *