Detect num. decimals, math constants, nan/inf for floats

Author: raulfraile

examples/simple_variables.php

@@ -7,6 +7,7 @@
 $var3 = 15.5;
 $var4 = 'hello world!';
 $var5 = false;
+$var6 = pi();
 
 $ladybug = new \Ladybug\Dumper();
-echo $ladybug->dump($var1, $var2, $var3, $var4, $var5);
+echo $ladybug->dump($var1, $var2, $var3, $var4, $var5, $var6);

src/Ladybug/Type/FloatType.php

@@ -21,6 +21,18 @@ class FloatType extends AbstractType
 
     const TYPE_ID = 'float';
 
+    protected $decimals = 0;
+
+    /** @var boolean $nan Whether the variable is NaN or not */
+    protected $nan = false;
+
+    /** @var boolean $infinite Whether the variable is infinite or not */
+    protected $infinite = false;
+
+    /** @var string $mathConstant Mathematical constant name */
+    protected $mathConstant = null;
+
+
     /**
      * Constructor.
      */
@@ -41,6 +53,77 @@ public function load($var, $level = 1)
         }
 
         parent::load($var, $level);
+
+        $this->decimals = strlen(substr(strrchr($var, "."), 1));
+        $this->infinite = is_infinite($var);
+        $this->nan = is_nan($var);
+        $this->mathConstant = $this->detectMathConstant($var, $this->decimals);
+    }
+
+    /**
+     * Checks whether the variable is NaN.
+     *
+     * @return bool
+     */
+    public function isNan()
+    {
+        return $this->nan;
+    }
+
+    /**
+     * Checks whether the variable is infinite.
+     *
+     * @return bool
+     */
+    public function isInfinite()
+    {
+        return $this->infinite;
     }
 
+    /**
+     * Gets the mathematical constant name, if any.
+     *
+     * @return string
+     */
+    public function getMathConstant()
+    {
+        return $this->mathConstant;
+    }
+
+    public function detectMathConstant($var, $precision)
+    {
+        $constants = array(
+            'pi' => array(
+                'value' => M_PI,
+                'min_precision' => 4
+            ),
+            'e' => array(
+                'value' => M_E,
+                'min_precision' => 4
+            ),
+            'euler_mascheroni' => array(
+                'value' => M_EULER,
+                'min_precision' => 4
+            ),
+            'conway' => array(
+                'value' => 1.303577269,
+                'min_precision' => 4
+            )
+        );
+
+        foreach ($constants as $name => $item) {
+            if (0 === bccomp($var, $item['value'], max($precision - 1, $item['min_precision']))) {
+                return $name;
+            }
+        }
+
+        return null;
+    }
+
+    public function getDecimals()
+    {
+        return $this->decimals;
+    }
+
+
 }

tests/Ladybug/Tests/Type/FloatTypeTest.php

@@ -22,6 +22,9 @@ public function testLoaderForValidValues()
         $this->type->load($var);
         $this->assertEquals($var, $this->type->getValue());
         $this->assertEquals(1, $this->type->getLevel());
+        $this->assertEquals(3, $this->type->getDecimals());
+        $this->assertFalse($this->type->isNan());
+        $this->assertFalse($this->type->isInfinite());
     }
 
     public function testLoaderForOtherType()
@@ -33,4 +36,28 @@ public function testLoaderForOtherType()
         $this->type->load($var);
     }
 
+    public function testNanValue()
+    {
+        $var = acos(1.01);
+
+        $this->type->load($var);
+        $this->assertTrue($this->type->isNan());
+    }
+
+    public function testInfiniteValue()
+    {
+        $var = log(0);
+
+        $this->type->load($var);
+        $this->assertTrue($this->type->isInfinite());
+    }
+
+    public function testPiMathConstantDetection()
+    {
+        $var = pi();
+
+        $this->type->load($var);
+        $this->assertEquals('pi', $this->type->getMathConstant());
+    }
+
 }