Introduce a function, `wp_attachment_is( $type, $post = 0 )`, to collapse the logic for determining whether an attachment is an `image`, `audio`, or `video`.

This is admittedly a first pass. There needs to be a generic handler for when any other type is passed, but for now it accepts the whitelist.

See #25275.


git-svn-id: https://develop.svn.wordpress.org/trunk@31645 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/edit-form-advanced.php

@@ -52,9 +52,9 @@ if ( $post_ID == get_option( 'page_for_posts' ) && empty( $post->post_content )
 
 $thumbnail_support = current_theme_supports( 'post-thumbnails', $post_type ) && post_type_supports( $post_type, 'thumbnail' );
 if ( ! $thumbnail_support && 'attachment' === $post_type && $post->post_mime_type ) {
-	if ( 0 === strpos( $post->post_mime_type, 'audio/' ) ) {
+	if ( wp_attachment_is( 'audio', $post ) ) {
 		$thumbnail_support = post_type_supports( 'attachment:audio', 'thumbnail' ) || current_theme_supports( 'post-thumbnails', 'attachment:audio' );
-	} elseif ( 0 === strpos( $post->post_mime_type, 'video/' ) ) {
+	} elseif ( wp_attachment_is( 'video', $post ) ) {
 		$thumbnail_support = post_type_supports( 'attachment:video', 'thumbnail' ) || current_theme_supports( 'post-thumbnails', 'attachment:video' );
 	}
 }
@@ -178,7 +178,7 @@ if ( 'attachment' == $post_type ) {
 	add_meta_box( 'submitdiv', __('Save'), 'attachment_submit_meta_box', null, 'side', 'core' );
 	add_action( 'edit_form_after_title', 'edit_form_image_editor' );
 
-	if ( 0 === strpos( $post->post_mime_type, 'audio/' ) ) {
+	if ( wp_attachment_is( 'audio', $post ) ) {
 		add_meta_box( 'attachment-id3', __( 'Metadata' ), 'attachment_id3_data_meta_box', null, 'normal', 'core' );
 	}
 } else {

src/wp-admin/includes/ajax-actions.php

@@ -2290,7 +2290,7 @@ function wp_ajax_save_attachment() {
 		}
 	}
 
-	if ( 0 === strpos( $post['post_mime_type'], 'audio/' ) ) {
+	if ( wp_attachment_is( 'audio', $post['ID'] ) ) {
 		$changed = false;
 		$id3data = wp_get_attachment_metadata( $post['ID'] );
 		if ( ! is_array( $id3data ) ) {
@@ -2448,7 +2448,7 @@ function wp_ajax_send_attachment_to_editor() {
 		$caption = isset( $attachment['post_excerpt'] ) ? $attachment['post_excerpt'] : '';
 		$title = ''; // We no longer insert title tags into <img> tags, as they are redundant.
 		$html = get_image_send_to_editor( $id, $caption, $title, $align, $url, (bool) $rel, $size, $alt );
-	} elseif ( 'video' === substr( $post->post_mime_type, 0, 5 ) || 'audio' === substr( $post->post_mime_type, 0, 5 )  ) {
+	} elseif ( wp_attachment_is( 'video', $post ) || wp_attachment_is( 'audio', $post )  ) {
 		$html = stripslashes_deep( $_POST['html'] );
 	}
 

src/wp-admin/includes/image.php

@@ -127,10 +127,10 @@ function wp_generate_attachment_metadata( $attachment_id, $file ) {
 		if ( $image_meta )
 			$metadata['image_meta'] = $image_meta;
 
-	} elseif ( preg_match( '#^video/#', get_post_mime_type( $attachment ) ) ) {
+	} elseif ( wp_attachment_is( 'video', $attachment ) ) {
 		$metadata = wp_read_video_metadata( $file );
 		$support = current_theme_supports( 'post-thumbnails', 'attachment:video' ) || post_type_supports( 'attachment:video', 'thumbnail' );
-	} elseif ( preg_match( '#^audio/#', get_post_mime_type( $attachment ) ) ) {
+	} elseif ( wp_attachment_is( 'audio', $attachment ) ) {
 		$metadata = wp_read_audio_metadata( $file );
 		$support = current_theme_supports( 'post-thumbnails', 'attachment:audio' ) || post_type_supports( 'attachment:audio', 'thumbnail' );
 	}

src/wp-admin/includes/media.php

@@ -2653,13 +2653,13 @@ function edit_form_image_editor( $post ) {
 			<?php if ( $open ) wp_image_editor( $attachment_id ); ?>
 		</div>
 	<?php
-	elseif ( $attachment_id && 0 === strpos( $post->post_mime_type, 'audio/' ) ):
+	elseif ( $attachment_id && wp_attachment_is( 'audio', $post ) ):
 
 		wp_maybe_generate_attachment_metadata( $post );
 
 		echo wp_audio_shortcode( array( 'src' => $att_url ) );
 
-	elseif ( $attachment_id && 0 === strpos( $post->post_mime_type, 'video/' ) ):
+	elseif ( $attachment_id && wp_attachment_is( 'video', $post ) ):
 
 		wp_maybe_generate_attachment_metadata( $post );
 

src/wp-includes/media.php

@@ -2976,9 +2976,9 @@ function wp_enqueue_media( $args = array() ) {
 
 		$thumbnail_support = current_theme_supports( 'post-thumbnails', $post->post_type ) && post_type_supports( $post->post_type, 'thumbnail' );
 		if ( ! $thumbnail_support && 'attachment' === $post->post_type && $post->post_mime_type ) {
-			if ( 0 === strpos( $post->post_mime_type, 'audio/' ) ) {
+			if ( wp_attachment_is( 'audio', $post ) ) {
 				$thumbnail_support = post_type_supports( 'attachment:audio', 'thumbnail' ) || current_theme_supports( 'post-thumbnails', 'attachment:audio' );
-			} elseif ( 0 === strpos( $post->post_mime_type, 'video/' ) ) {
+			} elseif ( wp_attachment_is( 'video', $post ) ) {
 				$thumbnail_support = post_type_supports( 'attachment:video', 'thumbnail' ) || current_theme_supports( 'post-thumbnails', 'attachment:video' );
 			}
 		}

src/wp-includes/post-template.php

@@ -1550,7 +1550,7 @@ function prepend_attachment($content) {
 	if ( empty($post->post_type) || $post->post_type != 'attachment' )
 		return $content;
 
-	if ( 0 === strpos( $post->post_mime_type, 'video' ) ) {
+	if ( wp_attachment_is( 'video', $post ) ) {
 		$meta = wp_get_attachment_metadata( get_the_ID() );
 		$atts = array( 'src' => wp_get_attachment_url() );
 		if ( ! empty( $meta['width'] ) && ! empty( $meta['height'] ) ) {
@@ -1561,7 +1561,7 @@ function prepend_attachment($content) {
 			$atts['poster'] = wp_get_attachment_url( get_post_thumbnail_id() );
 		}
 		$p = wp_video_shortcode( $atts );
-	} elseif ( 0 === strpos( $post->post_mime_type, 'audio' ) ) {
+	} elseif ( wp_attachment_is( 'audio', $post ) ) {
 		$p = wp_audio_shortcode( array( 'src' => wp_get_attachment_url() ) );
 	} else {
 		$p = '<p class="attachment">';

src/wp-includes/post.php

@@ -5070,29 +5070,57 @@ function wp_get_attachment_thumb_url( $post_id = 0 ) {
 	return apply_filters( 'wp_get_attachment_thumb_url', $url, $post->ID );
 }
 
+/**
+ * Verfify the attachment as being of a specific type
+ *
+ * @param string      $type    Type: image, audio, or video.
+ * @param int|WP_Post $post_id Optional. Default 0.
+ * @return bool
+ */
+function wp_attachment_is( $type, $post_id = 0 ) {
+	if ( ! $post = get_post( $post_id ) ) {
+		return false;
+	}
+
+	if ( ! $file = get_attached_file( $post->ID ) ) {
+		return false;
+	}
+
+	if ( 0 === strpos( $post->post_mime_type, $type . '/' ) ) {
+		return true;
+	}
+
+	$check = wp_check_filetype( $file );
+	if ( empty( $check['ext'] ) || 'import' !== $post->post_mime_type ) {
+		return false;
+	}
+	$ext = $check['ext'];
+
+	switch ( $type ) {
+	case 'image':
+		$image_exts = array( 'jpg', 'jpeg', 'jpe', 'gif', 'png' );
+		return in_array( $ext, $image_exts );
+
+	case 'audio':
+		return in_array( $ext, wp_get_audio_extensions() );
+
+	case 'video':
+		return in_array( $ext, wp_get_video_extensions() );
+	}
+
+	return false;
+}
+
 /**
  * Check if the attachment is an image.
  *
  * @since 2.1.0
  *
- * @param int $post_id Optional. Attachment ID. Default 0.
+ * @param int|WP_Post $post Optional. Attachment ID. Default 0.
  * @return bool Whether the attachment is an image.
  */
-function wp_attachment_is_image( $post_id = 0 ) {
+function wp_attachment_is_image( $post = 0 ) {
-	$post_id = (int) $post_id;
+	return wp_attachment_is( 'image', $post );
-	if ( !$post = get_post( $post_id ) )
-		return false;
-
-	if ( !$file = get_attached_file( $post->ID ) )
-		return false;
-
-	$ext = preg_match('/\.([^.]+)$/', $file, $matches) ? strtolower($matches[1]) : false;
-
-	$image_exts = array( 'jpg', 'jpeg', 'jpe', 'gif', 'png' );
-
-	if ( 'image/' == substr($post->post_mime_type, 0, 6) || $ext && 'import' == $post->post_mime_type && in_array($ext, $image_exts) )
-		return true;
-	return false;
 }
 
 /**