Ticket #42411: 42411.1.diff

src/wp-admin/customize.php

@@ -60 +60 @@
         }
 }
 
+$is_theme_switch_unavailable = (
+        ! $wp_customize->is_theme_active()
+        &&
+        ! $wp_customize->branching()
+        &&
+        $wp_customize->changeset_post_id()
+        &&
+        in_array(
+                get_post_status( $wp_customize->changeset_post_id() ),
+                array_diff( get_post_stati(), array( 'auto-draft', 'publish', 'trash', 'inherit', 'private' ) ),
+                true
+        )
+);
+if ( $is_theme_switch_unavailable ) {
+        $message = sprintf(
+                /* translators: %s is URL to Customizer with the Publish Settings section auto-focused */
+                __( 'Because you have drafted or scheduled changes, live previewing other themes is currently disabled. Please <a href="%s">publish your changes</a>, or wait until they publish to preview new themes. ' ),
+                add_query_arg(
+                        array(
+                                'autofocus[section]' => 'publish_settings',
+                                'return' => admin_url( 'themes.php' ),
+                        ),
+                        admin_url( 'customize.php' )
+                )
+        );
+
+        wp_die(
+                '<h1>' . __( 'Cheatin&#8217; uh?' ) . '</h1>' .
+                '<p>' . $message . '</p>',
+                403
+        );
+}
+
 
 wp_reset_vars( array( 'url', 'return', 'autofocus' ) );
 if ( ! empty( $url ) ) {

src/wp-admin/theme-install.php

@@ -123 +123 @@
 
 include(ABSPATH . 'wp-admin/admin-header.php');
 
+$is_customize_preview_available = true;
+
+/** This filter is documented in wp-includes/class-wp-customize-manager.php */
+if ( ! apply_filters( 'customize_changeset_branching', false ) ) {
+        $is_customize_preview_available = count( get_posts( array(
+                'post_type' => 'customize_changeset',
+                'post_status' => array_diff( get_post_stati(), array( 'auto-draft', 'publish', 'trash', 'inherit', 'private' ) ),
+                'author' => 'any',
+                'posts_per_page' => 1,
+                'no_found_rows' => true,
+                'cache_results' => true,
+                'update_post_meta_cache' => false,
+                'update_post_term_cache' => false,
+                'lazy_load_term_meta' => false,
+        ) ) ) === 0;
+}
+
 ?>
 <div class="wrap">
         <h1 class="wp-heading-inline"><?php echo esc_html( $title ); ?></h1>
@@ -150 +167 @@
                 <p><?php _e( 'The Theme Installer screen requires JavaScript.' ); ?></p>
         </div>
 
+        <?php if ( ! $is_customize_preview_available ) : ?>
+                <div class="notice notice-info">
+                        <p>
+                                <?php
+                                printf(
+                                        /* translators: %s is URL to Customizer with the Publish Settings section auto-focused */
+                                        __( 'Because you have drafted or scheduled changes, live previewing other themes is currently disabled. Please <a href="%s">publish your changes</a>, or wait until they publish to preview new themes. ' ),
+                                        add_query_arg( 'autofocus[section]', 'publish_settings', admin_url( 'customize.php' ) )
+                                );
+                                ?>
+                        </p>
+                </div>
+        <?php endif; ?>
+
         <div class="upload-theme">
         <?php install_themes_upload(); ?>
         </div>
@@ -277 +308 @@
                                 <# if ( data.activate_url ) { #>
                                         <a class="button button-primary activate" href="{{ data.activate_url }}" aria-label="<?php echo esc_attr( $aria_label ); ?>"><?php _e( 'Activate' ); ?></a>
                                 <# } #>
-                                <# if ( data.customize_url ) { #>
+                                <# if ( data.customize_url && <?php echo wp_json_encode( $is_customize_preview_available ); ?> ) { #>
                                         <a class="button load-customize" href="{{ data.customize_url }}"><?php _e( 'Live Preview' ); ?></a>
                                 <# } else { #>
                                         <button class="button preview install-theme-preview"><?php _e( 'Preview' ); ?></button>

src/wp-admin/themes.php

@@ -148 +148 @@
 wp_enqueue_script( 'updates' );
 
 require_once( ABSPATH . 'wp-admin/admin-header.php' );
+
+$is_customize_preview_available = true;
+
+/** This filter is documented in wp-includes/class-wp-customize-manager.php */
+if ( ! apply_filters( 'customize_changeset_branching', false ) ) {
+        $is_customize_preview_available = count( get_posts( array(
+                'post_type' => 'customize_changeset',
+                'post_status' => array_diff( get_post_stati(), array( 'auto-draft', 'publish', 'trash', 'inherit', 'private' ) ),
+                'author' => 'any',
+                'posts_per_page' => 1,
+                'no_found_rows' => true,
+                'cache_results' => true,
+                'update_post_meta_cache' => false,
+                'update_post_term_cache' => false,
+                'lazy_load_term_meta' => false,
+        ) ) ) === 0;
+}
+
 ?>
 
 <div class="wrap">
@@ -178 +196 @@
 <?php
 endif;
 
+if ( ! $is_customize_preview_available ) :
+        ?>
+        <div class="notice notice-info">
+                <p>
+                        <?php
+                        printf(
+                                /* translators: %s is URL to Customizer with the Publish Settings section auto-focused */
+                                __( 'Because you have drafted or scheduled changes, live previewing other themes is currently disabled. Please <a href="%s">publish your changes</a>, or wait until they publish to preview new themes. ' ),
+                                add_query_arg( 'autofocus[section]', 'publish_settings', admin_url( 'customize.php' ) )
+                        );
+                        ?>
+                </p>
+        </div>
+        <?php
+endif;
+
 $ct = wp_get_theme();
 
 if ( $ct->errors() && ( ! is_multisite() || current_user_can( 'manage_network_themes' ) ) ) {
@@ -296 +330 @@
                         $aria_label = sprintf( _x( 'Activate %s', 'theme' ), '{{ data.name }}' );
                         ?>
                         <a class="button activate" href="<?php echo $theme['actions']['activate']; ?>" aria-label="<?php echo esc_attr( $aria_label ); ?>"><?php _e( 'Activate' ); ?></a>
-                        <?php if ( current_user_can( 'edit_theme_options' ) && current_user_can( 'customize' ) ) { ?>
+                        <?php if ( current_user_can( 'edit_theme_options' ) && current_user_can( 'customize' ) && $is_customize_preview_available ) { ?>
                                 <a class="button button-primary load-customize hide-if-no-customize" href="<?php echo $theme['actions']['customize']; ?>"><?php _e( 'Live Preview' ); ?></a>
                         <?php } ?>
                 <?php } ?>
@@ -431 +465 @@
                                 $aria_label = sprintf( _x( 'Activate %s', 'theme' ), '{{ data.name }}' );
                                 ?>
                                 <a class="button activate" href="{{{ data.actions.activate }}}" aria-label="<?php echo $aria_label; ?>"><?php _e( 'Activate' ); ?></a>
-                                <a class="button button-primary load-customize hide-if-no-customize" href="{{{ data.actions.customize }}}"><?php _e( 'Live Preview' ); ?></a>
+                                <?php if ( $is_customize_preview_available ) : ?>
+                                        <a class="button button-primary load-customize hide-if-no-customize" href="{{{ data.actions.customize }}}"><?php _e( 'Live Preview' ); ?></a>
+                                <?php endif; ?>
                         <# } #>
                 </div>
         </div>
@@ -492 +528 @@
                                 <# if ( data.actions.activate ) { #>
                                         <a href="{{{ data.actions.activate }}}" class="button activate" aria-label="<?php echo $aria_label; ?>"><?php _e( 'Activate' ); ?></a>
                                 <# } #>
-                                <a href="{{{ data.actions.customize }}}" class="button button-primary load-customize hide-if-no-customize"><?php _e( 'Live Preview' ); ?></a>
+                                <?php if ( $is_customize_preview_available ) : ?>
+                                        <a href="{{{ data.actions.customize }}}" class="button button-primary load-customize hide-if-no-customize"><?php _e( 'Live Preview' ); ?></a>
+                                <?php endif; ?>
                         </div>
 
                         <# if ( ! data.active && data.actions['delete'] ) { #>

src/wp-includes/class-wp-customize-manager.php

@@ -612 +612 @@
                 if ( empty( $this->_changeset_uuid ) ) {
                         $changeset_uuid = null;
 
-                        if ( ! $this->branching() && $this->is_theme_active() ) {
+                        if ( ! $this->branching() ) {
                                 $unpublished_changeset_posts = $this->get_changeset_posts( array(
                                         'post_status' => array_diff( get_post_stati(), array( 'auto-draft', 'publish', 'trash', 'inherit', 'private' ) ),
                                         'exclude_restore_dismissed' => false,
@@ -782 +782 @@
                  *
                  * @since 4.9.0
                  *
-                 * @param bool                 $allow_branching Whether branching is allowed. If `false`, the default,
-                 *                                              then only one saved changeset exists at a time.
-                 * @param WP_Customize_Manager $wp_customize    Manager instance.
+                 * @param bool $allow_branching Whether branching is allowed. If `false`, the default,
+                 *                              then only one saved changeset exists at a time.
                  */
-                $this->branching = apply_filters( 'customize_changeset_branching', $this->branching, $this );
+                $this->branching = apply_filters( 'customize_changeset_branching', $this->branching );
 
                 return $this->branching;
         }

tests/phpunit/tests/customize/manager.php

@@ -197 +197 @@
                 ) );
                 $this->assertNotContains( $wp_customize->changeset_uuid(), array( $uuid1, $uuid2 ) );
                 $this->assertEmpty( $wp_customize->changeset_post_id() );
-
-                // Make sure existing changeset is not autoloaded in the case of previewing a theme switch.
-                switch_theme( 'twentyseventeen' );
-                $wp_customize = new WP_Customize_Manager( array(
-                        'changeset_uuid' => false, // Cause UUID to be deferred.
-                        'branching' => false,
-                        'theme' => 'twentyfifteen',
-                ) );
-                $this->assertEmpty( $wp_customize->changeset_post_id() );
         }
 
         /**