diff -r 000000000000 -r d970ebf37754 wp/wp-admin/includes/revision.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/wp/wp-admin/includes/revision.php	Wed Nov 06 03:21:17 2013 +0000
@@ -0,0 +1,224 @@
+<?php
+/**
+ * WordPress Administration Revisions API
+ *
+ * @package WordPress
+ * @subpackage Administration
+ */
+
+/**
+ * Get the revision UI diff.
+ *
+ * @since 3.6.0
+ *
+ * @param object|int $post         The post object. Also accepts a post ID.
+ * @param int        $compare_from The revision ID to compare from.
+ * @param int        $compare_to   The revision ID to come to.
+ *
+ * @return array|bool Associative array of a post's revisioned fields and their diffs.
+ *                    Or, false on failure.
+ */
+function wp_get_revision_ui_diff( $post, $compare_from, $compare_to ) {
+	if ( ! $post = get_post( $post ) )
+		return false;
+
+	if ( $compare_from ) {
+		if ( ! $compare_from = get_post( $compare_from ) )
+			return false;
+	} else {
+		// If we're dealing with the first revision...
+		$compare_from = false;
+	}
+
+	if ( ! $compare_to = get_post( $compare_to ) )
+		return false;
+
+	// If comparing revisions, make sure we're dealing with the right post parent.
+	// The parent post may be a 'revision' when revisions are disabled and we're looking at autosaves.
+	if ( $compare_from && $compare_from->post_parent !== $post->ID && $compare_from->ID !== $post->ID )
+		return false;
+	if ( $compare_to->post_parent !== $post->ID && $compare_to->ID !== $post->ID )
+		return false;
+
+	if ( $compare_from && strtotime( $compare_from->post_date_gmt ) > strtotime( $compare_to->post_date_gmt ) ) {
+		$temp = $compare_from;
+		$compare_from = $compare_to;
+		$compare_to = $temp;
+	}
+
+	// Add default title if title field is empty
+	if ( $compare_from && empty( $compare_from->post_title ) )
+		$compare_from->post_title = __( '(no title)' );
+	if ( empty( $compare_to->post_title ) )
+		$compare_to->post_title = __( '(no title)' );
+
+	$return = array();
+
+	foreach ( _wp_post_revision_fields() as $field => $name ) {
+		/**
+		 * Contextually filter a post revision field.
+		 *
+		 * The dynamic portion of the hook name, $field, corresponds to each of the post
+		 * fields of the revision object being iterated over in a foreach statement.
+		 *
+		 * @since 3.6.0
+		 *
+		 * @param string  $compare_from->$field The current revision field to compare to or from.
+		 * @param string  $field                The current revision field.
+		 * @param WP_Post $compare_from         The revision post object to compare to or from.
+		 * @param string  null                  The context of whether the current revision is the old or the new one. Values are 'to' or 'from'.
+		 */
+		$content_from = $compare_from ? apply_filters( "_wp_post_revision_field_$field", $compare_from->$field, $field, $compare_from, 'from' ) : '';
+
+		/** This filter is documented in wp-admin/includes/revision.php */
+		$content_to = apply_filters( "_wp_post_revision_field_$field", $compare_to->$field, $field, $compare_to, 'to' );
+
+		$diff = wp_text_diff( $content_from, $content_to, array( 'show_split_view' => true ) );
+
+		if ( ! $diff && 'post_title' === $field ) {
+			// It's a better user experience to still show the Title, even if it didn't change.
+			// No, you didn't see this.
+			$diff = '<table class="diff"><colgroup><col class="content diffsplit left"><col class="content diffsplit middle"><col class="content diffsplit right"></colgroup><tbody><tr>';
+			$diff .= '<td>' . esc_html( $compare_from->post_title ) . '</td><td></td><td>' . esc_html( $compare_to->post_title ) . '</td>';
+			$diff .= '</tr></tbody>';
+			$diff .= '</table>';
+		}
+
+		if ( $diff ) {
+			$return[] = array(
+				'id' => $field,
+				'name' => $name,
+				'diff' => $diff,
+			);
+		}
+	}
+	return $return;
+}
+
+/**
+ * Prepare revisions for JavaScript.
+ *
+ * @since 3.6.0
+ *
+ * @param object|int $post                 The post object. Also accepts a post ID.
+ * @param int        $selected_revision_id The selected revision ID.
+ * @param int        $from                 Optional. The revision ID to compare from.
+ *
+ * @return array An associative array of revision data and related settings.
+ */
+function wp_prepare_revisions_for_js( $post, $selected_revision_id, $from = null ) {
+	$post = get_post( $post );
+	$revisions = $authors = array();
+	$now_gmt = time();
+
+	$revisions = wp_get_post_revisions( $post->ID, array( 'order' => 'ASC', 'check_enabled' => false ) );
+	// If revisions are disabled, we only want autosaves and the current post.
+	if ( ! wp_revisions_enabled( $post ) ) {
+		foreach ( $revisions as $revision_id => $revision ) {
+			if ( ! wp_is_post_autosave( $revision ) )
+				unset( $revisions[ $revision_id ] );
+		}
+		$revisions = array( $post->ID => $post ) + $revisions;
+	}
+
+	$show_avatars = get_option( 'show_avatars' );
+
+	cache_users( wp_list_pluck( $revisions, 'post_author' ) );
+
+	$can_restore = current_user_can( 'edit_post', $post->ID );
+
+	foreach ( $revisions as $revision ) {
+		$modified = strtotime( $revision->post_modified );
+		$modified_gmt = strtotime( $revision->post_modified_gmt );
+		if ( $can_restore ) {
+			$restore_link = str_replace( '&amp;', '&', wp_nonce_url(
+				add_query_arg(
+					array( 'revision' => $revision->ID,
+						'action' => 'restore' ),
+						admin_url( 'revision.php' )
+				),
+				"restore-post_{$revision->ID}"
+			) );
+		}
+
+		if ( ! isset( $authors[ $revision->post_author ] ) ) {
+			$authors[ $revision->post_author ] = array(
+				'id' => (int) $revision->post_author,
+				'avatar' => $show_avatars ? get_avatar( $revision->post_author, 32 ) : '',
+				'name' => get_the_author_meta( 'display_name', $revision->post_author ),
+			);
+		}
+
+		$autosave = (bool) wp_is_post_autosave( $revision );
+		$current = ! $autosave && $revision->post_modified_gmt === $post->post_modified_gmt;
+		if ( $current && ! empty( $current_id ) ) {
+			// If multiple revisions have the same post_modified_gmt, highest ID is current.
+			if ( $current_id < $revision->ID ) {
+				$revisions[ $current_id ]['current'] = false;
+				$current_id = $revision->ID;
+			} else {
+				$current = false;
+			}
+		} elseif ( $current ) {
+			$current_id = $revision->ID;
+		}
+
+		$revisions[ $revision->ID ] = array(
+			'id'         => $revision->ID,
+			'title'      => get_the_title( $post->ID ),
+			'author'     => $authors[ $revision->post_author ],
+			'date'       => date_i18n( __( 'M j, Y @ G:i' ), $modified ),
+			'dateShort'  => date_i18n( _x( 'j M @ G:i', 'revision date short format' ), $modified ),
+			'timeAgo'    => sprintf( __( '%s ago' ), human_time_diff( $modified_gmt, $now_gmt ) ),
+			'autosave'   => $autosave,
+			'current'    => $current,
+			'restoreUrl' => $can_restore ? $restore_link : false,
+		);
+	}
+
+	// If a post has been saved since the last revision (no revisioned fields were changed)
+	// we may not have a "current" revision. Mark the latest revision as "current".
+	if ( empty( $current_id ) ) {
+		if ( $revisions[ $revision->ID ]['autosave'] ) {
+			$revision = end( $revisions );
+			while ( $revision['autosave'] ) {
+				$revision = prev( $revisions );
+			}
+			$current_id = $revision['id'];
+		} else {
+			$current_id = $revision->ID;
+		}
+		$revisions[ $current_id ]['current'] = true;
+	}
+
+	// Now, grab the initial diff
+	$compare_two_mode = is_numeric( $from );
+	if ( ! $compare_two_mode ) {
+		$found = array_search( $selected_revision_id, array_keys( $revisions ) );
+		if ( $found ) {
+			$from = array_keys( array_slice( $revisions, $found - 1, 1, true ) );
+			$from = reset( $from );
+		} else {
+			$from = 0;
+		}
+	}
+
+	$from = absint( $from );
+
+	$diffs = array( array(
+		'id' => $from . ':' . $selected_revision_id,
+		'fields' => wp_get_revision_ui_diff( $post->ID, $from, $selected_revision_id ),
+	));
+
+	return array(
+		'postId'           => $post->ID,
+		'nonce'            => wp_create_nonce( 'revisions-ajax-nonce' ),
+		'revisionData'     => array_values( $revisions ),
+		'to'               => $selected_revision_id,
+		'from'             => $from,
+		'diffData'         => $diffs,
+		'baseUrl'          => parse_url( admin_url( 'revision.php' ), PHP_URL_PATH ),
+		'compareTwoMode'   => absint( $compare_two_mode ), // Apparently booleans are not allowed
+		'revisionIds'      => array_keys( $revisions ),
+	);
+}