v0.6

• Conform to PHPCS
• Add unit tests
• Introduce additional filters
• Apply post-type and post-status restrictions before performing redirects

tests/test-plugin.php

+<?php
+/**
+ * Class PluginTest
+ *
+ * @package ETH_Simple_Shortlinks
+ */
+
+/**
+ * Plugin test case.
+ */
+class PluginTest extends WP_UnitTestCase {
+	/**
+	 * Post ID for published tests.
+	 *
+	 * @var int
+	 */
+	protected static $post_id_published;
+
+	/**
+	 * Post ID for draft tests.
+	 *
+	 * @var int
+	 */
+	protected static $post_id_draft;
+
+	/**
+	 * Create a post to test with.
+	 */
+	public function setUp() {
+		parent::setUp();
+
+		static::$post_id_published = $this->factory->post->create();
+		static::$post_id_draft     = $this->factory->post->create(
+			array(
+				'post_status' => 'draft',
+			)
+		);
+	}
+
+	/**
+	 * Test shortlink overrides.
+	 */
+	public function test_shortlink_filters() {
+		$expected_published = user_trailingslashit( home_url( 'p/' . static::$post_id_published ) );
+		$expected_draft     = add_query_arg( 'p', static::$post_id_draft, user_trailingslashit( home_url() ) );
+
+		$this->assertEquals( $expected_published, wp_get_shortlink( static::$post_id_published ), 'Failed to assert that published post has a simple shortlink.' );
+		$this->assertEquals( $expected_draft, wp_get_shortlink( static::$post_id_draft ), 'Failed to assert that draft post did not have its shortlink modified.' );
+	}
+
+	/**
+	 * Test redirect parsing for supported post.
+	 */
+	public function test_published_post_redirect() {
+		$fake_request = new \stdClass();
+		$fake_request->query_vars = array(
+			'p'             => static::$post_id_published,
+			'eth-shortlink' => true,
+		);
+
+		$redirect = ETH_Simple_Shortlinks::get_instance()->get_redirect_for_request( $fake_request );
+
+		$this->assertEquals( get_permalink( static::$post_id_published ), $redirect->destination, 'Failed to assert that redirect destination is post\'s permalink.' );
+		$this->assertEquals( 301, $redirect->status_code, 'Failed to assert that redirect status code is that for a permanent redirect.' );
+	}
+
+	/**
+	 * Test redirect parsing for unsupported post.
+	 */
+	public function test_draft_post_redirect() {
+		$fake_request = new \stdClass();
+		$fake_request->query_vars = array(
+			'p'             => static::$post_id_draft,
+			'eth-shortlink' => true,
+		);
+
+		$redirect = ETH_Simple_Shortlinks::get_instance()->get_redirect_for_request( $fake_request );
+
+		$this->assertNull( $redirect, 'Failed to assert that redirect is not generated for unsupported post status.' );
+	}
+}