feat: Adds an absolute method to return the absolute value of a BigNu…

…mber instance.

src/BigNumber.php

@@ -14,6 +14,13 @@ interface BigNumber
 {
     public const AUTOMATIC_SCALE = null;
 
+    /**
+     * Converts the current BigNumber to its absolute value.
+     *
+     * @return BigNumber A new BigNumber representing the absolute value.
+     */
+    public function absolute(): BigNumber;
+
     /**
      * Adds the current BigNumber (augend) with another BigNumber (addend).
      *

src/Internal/BigNumberBehavior.php

@@ -27,6 +27,11 @@ abstract public static function fromFloat(float $value, ?int $scale = BigNumber:
 
     abstract public static function fromString(string $value, ?int $scale = BigNumber::AUTOMATIC_SCALE): BigNumber;
 
+    public function absolute(): BigNumber
+    {
+        return static::fromString(value: (string)abs((float)$this->number->value));
+    }
+
     public function add(BigNumber $addend): BigNumber
     {
         $result = $this->mathOperations->add(augend: $this, addend: $addend);

tests/BigNumberTest.php

@@ -11,6 +11,23 @@
 
 final class BigNumberTest extends TestCase
 {
+    public function testAbsolute(): void
+    {
+        /** @Given a BigNumber instance */
+        $negativeValue = -10.155;
+        $number = LargeNumber::fromFloat(value: $negativeValue);
+
+        /** @When calling the absolute method */
+        $actual = $number->absolute();
+
+        /** @Then the result should be an instance of BigNumber */
+        self::assertInstanceOf(BigNumber::class, $actual);
+
+        /** @And the value should be the absolute value of the negative number */
+        self::assertSame(abs($negativeValue), $actual->toFloat());
+        self::assertSame(sprintf('%s', abs($negativeValue)), $actual->toString());
+    }
+
     #[DataProvider('providerForTestAdd')]
     public function testAdd(int $scale, mixed $value, mixed $other, array $expected): void
     {