Adds formatting string to defined thousands separator

Author: elliotjreed

src/ElliotJReed/Maths/Number.php

@@ -17,14 +17,14 @@ public function __construct(self | int | float | string $number = 0, private rea
         $this->number = $this->castNumberToString($number);
     }
 
-    public function asString(?int $decimalPlaces = null): string
+    public function asString(?int $decimalPlaces = null, string $thousandsSeparator = ''): string
     {
         if (null !== $decimalPlaces) {
             if ($decimalPlaces < 0) {
                 throw new InvalidDecimalPlaces('Decimal places must be a whole number greater than or equal to 0. Invalid decimal places number: ' . $decimalPlaces);
             }
 
-            return \number_format((float) $this->number, $decimalPlaces, '.', '');
+            return \number_format((float) $this->number, $decimalPlaces, '.', $thousandsSeparator);
         }
 
         if (\str_contains($this->number, '.')) {

tests/ElliotJReed/Maths/NumberTest.php

@@ -13,20 +13,29 @@ final class NumberTest extends TestCase
 {
     public function testItReturnsNumberAsStringToDefinedDecimalPlaces(): void
     {
-        $number = new Number(0.29533);
+        $number = new Number(10000.29533);
 
-        $this->assertSame('0.30', $number->asString(2));
-        $this->assertSame('0.29533', $number->asString());
-        $this->assertSame(0.29533, $number->asFloat());
+        $this->assertSame('10000.30', $number->asString(2));
+        $this->assertSame('10000.29533', $number->asString());
+        $this->assertSame(10000.29533, $number->asFloat());
     }
 
     public function testItReturnsNumberAsWholeNumberStringToZeroDefinedDecimalPlaces(): void
     {
-        $number = new Number(1.29533);
+        $number = new Number(10000.29533);
 
-        $this->assertSame('1', $number->asString(0));
-        $this->assertSame('1.29533', $number->asString());
-        $this->assertSame(1.29533, $number->asFloat());
+        $this->assertSame('10000', $number->asString(0));
+        $this->assertSame('10000.29533', $number->asString());
+        $this->assertSame(10000.29533, $number->asFloat());
+    }
+
+    public function testItReturnsNumberAsStringToDefinedThousandsSeparator(): void
+    {
+        $number = new Number(10000.29533);
+
+        $this->assertSame('10,000.30', $number->asString(2, ','));
+        $this->assertSame('10000.29533', $number->asString());
+        $this->assertSame(10000.29533, $number->asFloat());
     }
 
     public function testItThrowsExceptionWhenDecimalPlacesArgumentIsLessThanZeroWhenReturningNumberAsAString(): void