ISSUE-15: Implemented BooleanToStringTransformer

Author: raymondschouten

src/BooleanToStringTransformer.php

@@ -0,0 +1,104 @@
+<?php
+/**
+ * Copyright (c) 2017 DarkWeb Design
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+namespace DarkWebDesign\SymfonyAddon\Transformer;
+
+use Symfony\Component\Form\DataTransformerInterface;
+use Symfony\Component\Form\Exception\TransformationFailedException;
+
+/**
+ * Transforms between a boolean and a string.
+ *
+ * @author Raymond Schouten
+ *
+ * @since 2.3
+ */
+class BooleanToStringTransformer implements DataTransformerInterface
+{
+    /** @var string */
+    private $trueValue;
+
+    /** @var string */
+    private $falseValue;
+
+    /**
+     * Constructor.
+     *
+     * @param string $trueValue
+     * @param string $falseValue
+     */
+    public function __construct($trueValue = 'true', $falseValue = 'false')
+    {
+        $this->trueValue = $trueValue;
+        $this->falseValue = $falseValue;
+    }
+
+    /**
+     * Transforms a value from the original representation to a transformed representation.
+     *
+     * @param bool $value
+     *
+     * @return string
+     *
+     * @throws \Symfony\Component\Form\Exception\TransformationFailedException
+     */
+    public function transform($value)
+    {
+        if (null === $value) {
+            return null;
+        }
+
+        if (!is_bool($value)) {
+            throw new TransformationFailedException('Expected a boolean.');
+        }
+
+        return $value ? $this->trueValue : $this->falseValue;
+    }
+
+    /**
+     * Transforms a value from the transformed representation to its original representation.
+     *
+     * @param string $value
+     *
+     * @return bool
+     *
+     * @throws \Symfony\Component\Form\Exception\TransformationFailedException
+     */
+    public function reverseTransform($value)
+    {
+        if (null === $value || '' === $value) {
+            return null;
+        }
+
+        if (!is_scalar($value)) {
+            throw new TransformationFailedException('Expected a scalar.');
+        }
+
+        $value = (string) $value;
+
+        if (!($value === $this->trueValue || $value === $this->falseValue)) {
+            throw new TransformationFailedException(
+                sprintf('Expected a string "%s" or "%s".', $this->trueValue, $this->falseValue)
+            );
+        }
+
+        return $value === $this->trueValue;
+    }
+}