added tests for headings

composer.json

@@ -1,7 +1,7 @@
 {
     "name": "massivedynamic/parkdown",
     "type": "library",
-	"version": "1.1.2",
+	"version": "v1.2.0",
     "license": "MIT",
     "autoload": {
         "psr-4": {

tests/HeadingsTest.php

@@ -0,0 +1,65 @@
+<?php declare(strict_types=1);
+
+use PHPUnit\Framework\TestCase;
+
+final class HeadingsTest extends TestCase {
+	public function testH1ParsesCorrectly() : void {
+		$source = "
+# This is an H1
+		";
+		$target = "
+		<h1>This is an H1</h1>
+		";
+
+		[$source, $result] = createTest($source, $target);
+		$this->assertEquals($source, $result);
+	}
+	
+	public function testH2ParsesCorrectly() : void {
+		$source = "
+## This is an H2
+		";
+		$target = "
+		<h2>This is an H2</h2>
+		";
+
+		[$source, $result] = createTest($source, $target);
+		$this->assertEquals($source, $result);
+	}
+
+	public function testH3ParsesCorrectly() : void {
+		$source = "
+### This is an H3
+		";
+		$target = "
+		<h3>This is an H3</h3>
+		";
+
+		[$source, $result] = createTest($source, $target);
+		$this->assertEquals($source, $result);
+	}
+
+	public function testH4ParsesCorrectly() : void {
+		$source = "
+#### This is an H4
+		";
+		$target = "
+		<h4>This is an H4</h4>
+		";
+
+		[$source, $result] = createTest($source, $target);
+		$this->assertEquals($source, $result);
+	}
+
+	public function testH5ParsesCorrectly() : void {
+		$source = "
+##### This is an H5
+		";
+		$target = "
+		<h5>This is an H5</h5>
+		";
+
+		[$source, $result] = createTest($source, $target);
+		$this->assertEquals($source, $result);
+	}
+}