Recalibrate for Significance=0

Very peculiar implementation in Excel. PhpSpreadsheet will match it:
- FLOOR(8,0) is #DIV/0. This already matched, and is the only result I understand.
- CEILING(8,0) is 0 (already matched)
- FLOOR.MATH(8,0) is 0 (changed to match)
- FLOOR.PRECISE(8,0) is 0 (changed to match)
- CEILING.MATH(8,0) is 0 (already matched)
- CEILING.PRECISE(8,0) is 0 (already matched)

Author: oleibman

src/PhpSpreadsheet/Calculation/MathTrig/Floor.php

@@ -89,6 +89,9 @@ public static function math(mixed $number, mixed $significance = null, mixed $mo
             return $e->getMessage();
         }
 
+        if (empty($significance * $number)) {
+            return 0.0;
+        }
         if ($checkSigns) {
             if (($number > 0 && $significance < 0) || ($number < 0 && $significance > 0)) {
                 return ExcelError::VALUE();
@@ -146,6 +149,9 @@ public static function precise($number, $significance = 1)
         } catch (Exception $e) {
             return $e->getMessage();
         }
+        if (!$significance) {
+            return 0.0;
+        }
 
         return self::argumentsOkPrecise((float) $number, (float) $significance);
     }

tests/data/Calculation/MathTrig/FLOORMATH.php

@@ -8,7 +8,7 @@
     [-4, '-2.5, 2'],
     [2, '2.5, -2'],
     [0.0, '0.0, 1'],
-    ['#DIV/0!', '123.456, 0'],
+    'corrected with PR 4466' => [0.0, '123.456, 0'],
     [1.5, '1.5, 0.1'],
     [0.23, '0.234, 0.01'],
     [123, '123.456'],

tests/data/Calculation/MathTrig/FLOORPRECISE.php

@@ -8,7 +8,7 @@
     [-4, '-2.5, 2'],
     [2, '2.5, -2'],
     [0.0, '0.0, 1'],
-    ['#DIV/0!', '123.456, 0'],
+    'corrected with PR 4446' => [0.0, '123.456, 0'],
     [1.5, '1.5, 0.1'],
     [0.23, '0.234, 0.01'],
     [123, '123.456'],