Add test cases

tests/_data/views/filters/default.volt

@@ -0,0 +1 @@
+{{ robot.price|default(10.0) }}

tests/_data/views/filters/default_json_encode.volt

@@ -0,0 +1 @@
+{{ preparedParams|default([])|json_encode }}

tests/_data/views/layouts/compiler.volt

@@ -0,0 +1,3 @@
+{% if some_eval %}
+Clearly, the song is: {{ content() }}.
+{% endif %}

tests/unit/Compiler/CompileFileTest.php

@@ -0,0 +1,81 @@
+<?php
+
+/**
+ * This file is part of the Phalcon Framework.
+ *
+ * (c) Phalcon Team <[email protected]>
+ *
+ * For the full copyright and license information, please view the LICENSE.txt
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace Phalcon\Tests\Unit\Compiler;
+
+use Phalcon\Volt\Compiler;
+use PHPUnit\Framework\TestCase;
+
+class CompileFileTest extends TestCase
+{
+    public static function defaultFilterProvider(): array
+    {
+        return [
+            [
+                'default',
+                "<?= (empty(\$robot->price) ? (10.0) : (\$robot->price)) ?>\n",
+            ],
+
+            [
+                'default_json_encode',
+                "<?= json_encode((empty(\$preparedParams) ? ([]) : (\$preparedParams))) ?>\n",
+            ],
+        ];
+    }
+
+    /**
+     * Tests Phalcon\Mvc\View\Engine\Volt\Compiler :: compileFile()
+     *
+     * @author Phalcon Team <[email protected]>
+     * @since  2017-01-17
+     */
+    public function testMvcViewEngineVoltCompilerCompileFile(): void
+    {
+        $viewFile    = 'tests/_data/views/layouts/compiler.volt';
+        $compileFile = $viewFile . 'compiler.volt.php';
+
+        $expected = '<?php if ($some_eval) { ?>
+Clearly, the song is: <?= $this->getContent() ?>.
+<?php } ?>';
+
+        $volt = new Compiler();
+
+        $volt->compileFile($viewFile, $compileFile);
+        $this->assertEquals($expected, file_get_contents($compileFile));
+
+        unlink($compileFile);
+    }
+
+    /**
+     * Tests Phalcon\Mvc\View\Engine\Volt\Compiler :: compileFile()
+     *
+     * @issue https://github.com/phalcon/cphalcon/issues/13242
+     *
+     * @author       Phalcon Team <[email protected]>
+     * @since        2018-11-13
+     *
+     * @dataProvider defaultFilterProvider
+     */
+    public function testMvcViewEngineVoltCompilerCompileFileDefaultFilter(
+        string $view,
+        string $expected
+    ): void {
+        $viewFile = sprintf('tests/_data/views/filters/%s.volt', $view);
+        $compiledFile = $viewFile . '.php';
+
+        $volt = new Compiler();
+        $volt->compileFile($viewFile, $compiledFile);
+        $this->assertEquals($expected, file_get_contents($compiledFile));
+        //unlink($compiledFile);
+    }
+}