Permalinks: Add pretty permalinks for unattached attachments.

Previously, unattached attachments would have unsightly `/?attachment_id=1` URLs. As we've moved away from attachments being specifically attached to posts, instead being Media items, this has made the unattached URLs a more common occurrence.

We can breath easy once more, knowing that the world is a little bit safer from the horror of unnecessarily ugly URLs.

Props SergeyBiryukov, wonderboymusic, pento.

Fixes #1914.



git-svn-id: https://develop.svn.wordpress.org/trunk@34690 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/includes/post.php

@@ -1296,7 +1296,7 @@ function get_sample_permalink_html( $id, $new_title = null, $new_slug = null ) {
 			$view_link = get_preview_post_link( $post, array(), $draft_link );
 			$preview_target = " target='wp-preview-{$post->ID}'";
 		} else {
-			if ( 'publish' === $post->post_status ) {
+			if ( 'publish' === $post->post_status || 'attachment' === $post->post_type ) {
 				$view_link = get_permalink( $post );
 			} else {
 				// Allow non-published (private, future) to be viewed at a pretty permalink.
@@ -1310,7 +1310,7 @@ function get_sample_permalink_html( $id, $new_title = null, $new_slug = null ) {
 		$return = '<strong>' . __( 'Permalink:' ) . "</strong>\n";
 
 		if ( false !== $view_link ) {
-			$return .= '<a id="sample-permalink" href="' . esc_url( $view_link ) . '"' . $preview_target . '>' . $permalink . "</a>\n";
+			$return .= '<a id="sample-permalink" href="' . esc_url( $view_link ) . '"' . $preview_target . '>' . $view_link . "</a>\n";
 		} else {
 			$return .= '<span id="sample-permalink">' . $permalink . "</span>\n";
 		}

src/wp-includes/link-template.php

@@ -386,6 +386,9 @@ function get_attachment_link( $post = null, $leavename = false ) {
 
 	$post = get_post( $post );
 	$parent = ( $post->post_parent > 0 && $post->post_parent != $post->ID ) ? get_post( $post->post_parent ) : false;
+	if ( $parent && ! in_array( $parent->post_type, get_post_types() ) ) {
+		$parent = false;
+	}
 
 	if ( $wp_rewrite->using_permalinks() && $parent ) {
 		if ( 'page' == $parent->post_type )
@@ -403,6 +406,8 @@ function get_attachment_link( $post = null, $leavename = false ) {
 
 		if ( ! $leavename )
 			$link = str_replace( '%postname%', $name, $link );
+	} elseif ( $wp_rewrite->using_permalinks() && ! $leavename ) {
+		$link = home_url( user_trailingslashit( $post->post_name ) );
 	}
 
 	if ( ! $link )

src/wp-includes/query.php

@@ -3580,6 +3580,11 @@ class WP_Query {
 		// Check post status to determine if post should be displayed.
 		if ( !empty($this->posts) && ($this->is_single || $this->is_page) ) {
 			$status = get_post_status($this->posts[0]);
+			if ( 'attachment' === $this->posts[0]->post_type && 0 === (int) $this->posts[0]->post_parent ) {
+				$this->is_page = false;
+				$this->is_single = true;
+				$this->is_attachment = true;
+			}
 			$post_status_obj = get_post_status_object($status);
 			//$type = get_post_type($this->posts[0]);
 

tests/phpunit/tests/link.php

@@ -395,4 +395,58 @@ class Tests_Link extends WP_UnitTestCase {
 
 		$this->assertEquals( $non_pretty_permalink, get_permalink( $p ) );
 	}
+
+	/**
+	 * @ticket 1914
+	 */
+	public function test_unattached_attachment_has_a_pretty_permalink() {
+		global $wp_rewrite;
+		$wp_rewrite->set_permalink_structure('/%year%/%monthnum%/%day%/%postname%/');
+		$wp_rewrite->flush_rules();
+
+		$attachment_id = $this->factory->attachment->create_object( 'image.jpg', 0, array(
+			'post_mime_type' => 'image/jpeg',
+			'post_type' => 'attachment',
+			'post_title' => 'An Attachment!',
+			'post_status' => 'inherit',
+		) );
+
+		$attachment = get_post( $attachment_id );
+
+		$this->assertSame( home_url( user_trailingslashit( $attachment->post_name ) ), get_permalink( $attachment_id ) );
+	}
+
+	/**
+	 * @ticket 1914
+	 */
+	public function test_attachment_attached_to_non_existent_post_type_has_a_pretty_permalink() {
+		global $wp_rewrite, $wp_post_types;
+		$wp_rewrite->set_permalink_structure('/%year%/%monthnum%/%day%/%postname%/');
+
+		register_post_type( 'not_a_post_type', array( 'public' => true ) );
+
+		$wp_rewrite->flush_rules();
+
+		$post_id = $this->factory->post->create( array( 'post_type' => 'not_a_post_type' ) );
+
+		$attachment_id = $this->factory->attachment->create_object( 'image.jpg', $post_id, array(
+			'post_mime_type' => 'image/jpeg',
+			'post_type' => 'attachment',
+			'post_title' => 'An Attachment!',
+			'post_status' => 'inherit',
+		) );
+
+		$attachment = get_post( $attachment_id );
+
+		$this->assertSame( get_permalink( $post_id ) . user_trailingslashit( $attachment->post_name ), get_permalink( $attachment_id ) );
+
+		foreach( $wp_post_types as $id => $pt ) {
+			if ( 'not_a_post_type' === $pt->name ) {
+				unset( $wp_post_types[ $id ] );
+				break;
+			}
+		}
+
+		$this->assertSame( home_url( user_trailingslashit( $attachment->post_name ) ), get_permalink( $attachment_id ) );
+	}
 }