BC Math Calculator: add scale to add and subtract operations (#528)

* BC Math Calculator: add scale to add and subtract operations * add test for subtract * add string cast * style
moneyphp · Dec 6, 2018 · 42e55ab · 42e55ab
1 parent 665fe6e
commit 42e55ab
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Showing 2 changed files with 18 additions and 2 deletions.
diff --git a/src/Calculator/BcMathCalculator.php b/src/Calculator/BcMathCalculator.php
@@ -45,7 +45,7 @@ public function compare($a, $b)
      */
     public function add($amount, $addend)
     {
-        return bcadd($amount, $addend, 0);
+        return (string) Number::fromString(bcadd($amount, $addend, $this->scale));
     }
 
     /**
@@ -58,7 +58,7 @@ public function add($amount, $addend)
      */
     public function subtract($amount, $subtrahend)
     {
-        return bcsub($amount, $subtrahend, 0);
+        return (string) Number::fromString(bcsub($amount, $subtrahend, $this->scale));
     }
 
     /**

diff --git a/tests/Calculator/BcMathCalculatorTest.php b/tests/Calculator/BcMathCalculatorTest.php
@@ -56,4 +56,20 @@ public function it_compares_numbers_close_to_zero()
         $this->assertEquals(1, $this->getCalculator()->compare('1', '0.0005'));
         $this->assertEquals(1, $this->getCalculator()->compare('1', '0.000000000000000000000000005'));
     }
+
+    /**
+     * @test
+     */
+    public function it_uses_scale_for_add()
+    {
+        $this->assertEquals('0.00130154000000', $this->getCalculator()->add('0.00125148', '0.00005006'));
+    }
+
+    /**
+     * @test
+     */
+    public function it_uses_scale_for_subtract()
+    {
+        $this->assertEquals('0.00120142', $this->getCalculator()->subtract('0.00125148', '0.00005006'));
+    }
 }