Auto-embedding:

- We already match URLs on their own line, add another regex to match URLs in their own paragraphs.
- Always exclude the `\s<>"` characters when matching.
- Add more unit tests.

Props iseulde, azaozz.
Fixes #25387.
Built from https://develop.svn.wordpress.org/trunk@37627


git-svn-id: http://core.svn.wordpress.org/trunk@37595 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/class-wp-embed.php

@@ -334,8 +334,12 @@ class WP_Embed {
 		// Replace line breaks from all HTML elements with placeholders.
 		$content = wp_replace_in_html_tags( $content, array( "\n" => '<!-- wp-line-break -->' ) );
 
-		// Find URLs that are on their own line.
-		$content = preg_replace_callback( '|^(\s*)(https?://[^\s"]+)(\s*)$|im', array( $this, 'autoembed_callback' ), $content );
+		if ( preg_match( '#(^|\s|>)https?://#i', $content ) ) {
+			// Find URLs on their own line.
+			$content = preg_replace_callback( '|^(\s*)(https?://[^\s<>"]+)(\s*)$|im', array( $this, 'autoembed_callback' ), $content );
+			// Find URLs in their own paragraph.
+			$content = preg_replace_callback( '|(<p(?: [^>]*)?>\s*)(https?://[^\s<>"]+)(\s*<\/p>)|i', array( $this, 'autoembed_callback' ), $content );
+		}
 
 		// Put the line breaks back.
 		return str_replace( '<!-- wp-line-break -->', "\n", $content );

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.6-alpha-37626';
+$wp_version = '4.6-alpha-37627';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.