wp/wp-admin/includes/update.php
changeset 16 a86126ab1dd4
parent 9 177826044cd9
child 18 be944660c56a
--- a/wp/wp-admin/includes/update.php	Tue Oct 22 16:11:46 2019 +0200
+++ b/wp/wp-admin/includes/update.php	Tue Dec 15 13:49:49 2020 +0100
@@ -9,6 +9,8 @@
 /**
  * Selects the first update version from the update_core option.
  *
+ * @since 2.7.0
+ *
  * @return object|array|false The response from the API on success, false on failure.
  */
 function get_preferred_from_update_core() {
@@ -23,7 +25,9 @@
 }
 
 /**
- * Get available core updates.
+ * Gets available core updates.
+ *
+ * @since 2.7.0
  *
  * @param array $options Set $options['dismissed'] to true to show dismissed upgrades too,
  *                       set $options['available'] to false to skip not-dismissed updates.
@@ -52,7 +56,7 @@
 	$updates = $from_api->updates;
 	$result  = array();
 	foreach ( $updates as $update ) {
-		if ( $update->response == 'autoupdate' ) {
+		if ( 'autoupdate' === $update->response ) {
 			continue;
 		}
 
@@ -72,13 +76,13 @@
 }
 
 /**
- * Gets the best available (and enabled) Auto-Update for WordPress Core.
+ * Gets the best available (and enabled) Auto-Update for WordPress core.
  *
- * If there's 1.2.3 and 1.3 on offer, it'll choose 1.3 if the installation allows it, else, 1.2.3
+ * If there's 1.2.3 and 1.3 on offer, it'll choose 1.3 if the installation allows it, else, 1.2.3.
  *
  * @since 3.7.0
  *
- * @return array|false False on failure, otherwise the core update offering.
+ * @return object|false The core update offering on success, false on failure.
  */
 function find_core_auto_update() {
 	$updates = get_site_transient( 'update_core' );
@@ -86,12 +90,12 @@
 		return false;
 	}
 
-	include_once( ABSPATH . 'wp-admin/includes/class-wp-upgrader.php' );
+	require_once ABSPATH . 'wp-admin/includes/class-wp-upgrader.php';
 
 	$auto_update = false;
 	$upgrader    = new WP_Automatic_Updater;
 	foreach ( $updates->updates as $update ) {
-		if ( 'autoupdate' != $update->response ) {
+		if ( 'autoupdate' !== $update->response ) {
 			continue;
 		}
 
@@ -113,12 +117,14 @@
  *
  * @param string $version Version string to query.
  * @param string $locale  Locale to query.
- * @return bool|array False on failure. An array of checksums on success.
+ * @return array|false An array of checksums on success, false on failure.
  */
 function get_core_checksums( $version, $locale ) {
-	$url = $http_url = 'http://api.wordpress.org/core/checksums/1.0/?' . http_build_query( compact( 'version', 'locale' ), null, '&' );
+	$http_url = 'http://api.wordpress.org/core/checksums/1.0/?' . http_build_query( compact( 'version', 'locale' ), null, '&' );
+	$url      = $http_url;
 
-	if ( $ssl = wp_http_supports( array( 'ssl' ) ) ) {
+	$ssl = wp_http_supports( array( 'ssl' ) );
+	if ( $ssl ) {
 		$url = set_url_scheme( $url, 'https' );
 	}
 
@@ -130,9 +136,9 @@
 	if ( $ssl && is_wp_error( $response ) ) {
 		trigger_error(
 			sprintf(
-				/* translators: %s: support forums URL */
+				/* translators: %s: Support forums URL. */
 				__( 'An unexpected error occurred. Something may be wrong with WordPress.org or this server&#8217;s configuration. If you continue to have problems, please try the <a href="%s">support forums</a>.' ),
-				__( 'https://wordpress.org/support/' )
+				__( 'https://wordpress.org/support/forums/' )
 			) . ' ' . __( '(WordPress could not establish a secure connection to WordPress.org. Please contact your server administrator.)' ),
 			headers_sent() || WP_DEBUG ? E_USER_WARNING : E_USER_NOTICE
 		);
@@ -154,6 +160,10 @@
 }
 
 /**
+ * Dismisses core update.
+ *
+ * @since 2.7.0
+ *
  * @param object $update
  * @return bool
  */
@@ -164,6 +174,10 @@
 }
 
 /**
+ * Undismisses core update.
+ *
+ * @since 2.7.0
+ *
  * @param string $version
  * @param string $locale
  * @return bool
@@ -181,9 +195,13 @@
 }
 
 /**
- * @param string $version
- * @param string $locale
- * @return object|false
+ * Finds the available update for WordPress core.
+ *
+ * @since 2.7.0
+ *
+ * @param string $version Version string to find the update for.
+ * @param string $locale  Locale to find the update for.
+ * @return object|false The core update offering on success, false on failure.
  */
 function find_core_update( $version, $locale ) {
 	$from_api = get_site_transient( 'update_core' );
@@ -202,11 +220,14 @@
 }
 
 /**
+ * @since 2.3.0
+ *
  * @param string $msg
  * @return string
  */
 function core_update_footer( $msg = '' ) {
 	if ( ! current_user_can( 'update_core' ) ) {
+		/* translators: %s: WordPress version. */
 		return sprintf( __( 'Version %s' ), get_bloginfo( 'version', 'display' ) );
 	}
 
@@ -229,21 +250,33 @@
 
 	switch ( $cur->response ) {
 		case 'development':
-			/* translators: 1: WordPress version number, 2: WordPress updates admin screen URL */
-			return sprintf( __( 'You are using a development version (%1$s). Cool! Please <a href="%2$s">stay updated</a>.' ), get_bloginfo( 'version', 'display' ), network_admin_url( 'update-core.php' ) );
+			return sprintf(
+				/* translators: 1: WordPress version number, 2: URL to WordPress Updates screen. */
+				__( 'You are using a development version (%1$s). Cool! Please <a href="%2$s">stay updated</a>.' ),
+				get_bloginfo( 'version', 'display' ),
+				network_admin_url( 'update-core.php' )
+			);
 
 		case 'upgrade':
-			return '<strong><a href="' . network_admin_url( 'update-core.php' ) . '">' . sprintf( __( 'Get Version %s' ), $cur->current ) . '</a></strong>';
+			return sprintf(
+				'<strong><a href="%s">%s</a></strong>',
+				network_admin_url( 'update-core.php' ),
+				/* translators: %s: WordPress version. */
+				sprintf( __( 'Get Version %s' ), $cur->current )
+			);
 
 		case 'latest':
 		default:
+			/* translators: %s: WordPress version. */
 			return sprintf( __( 'Version %s' ), get_bloginfo( 'version', 'display' ) );
 	}
 }
 
 /**
+ * @since 2.3.0
+ *
  * @global string $pagenow
- * @return false|void
+ * @return void|false
  */
 function update_nag() {
 	if ( is_multisite() && ! current_user_can( 'update_core' ) ) {
@@ -252,25 +285,25 @@
 
 	global $pagenow;
 
-	if ( 'update-core.php' == $pagenow ) {
+	if ( 'update-core.php' === $pagenow ) {
 		return;
 	}
 
 	$cur = get_preferred_from_update_core();
 
-	if ( ! isset( $cur->response ) || $cur->response != 'upgrade' ) {
+	if ( ! isset( $cur->response ) || 'upgrade' !== $cur->response ) {
 		return false;
 	}
 
 	$version_url = sprintf(
-		/* translators: %s: WordPress version */
+		/* translators: %s: WordPress version. */
 		esc_url( __( 'https://wordpress.org/support/wordpress-version/version-%s/' ) ),
 		sanitize_title( $cur->current )
 	);
 
 	if ( current_user_can( 'update_core' ) ) {
 		$msg = sprintf(
-			/* translators: 1: URL to WordPress release notes, 2: new WordPress version, 3: URL to network admin, 4: accessibility text */
+			/* translators: 1: URL to WordPress release notes, 2: New WordPress version, 3: URL to network admin, 4: Accessibility text. */
 			__( '<a href="%1$s">WordPress %2$s</a> is available! <a href="%3$s" aria-label="%4$s">Please update now</a>.' ),
 			$version_url,
 			$cur->current,
@@ -279,16 +312,21 @@
 		);
 	} else {
 		$msg = sprintf(
-			/* translators: 1: URL to WordPress release notes, 2: new WordPress version */
+			/* translators: 1: URL to WordPress release notes, 2: New WordPress version. */
 			__( '<a href="%1$s">WordPress %2$s</a> is available! Please notify the site administrator.' ),
 			$version_url,
 			$cur->current
 		);
 	}
-	echo "<div class='update-nag'>$msg</div>";
+
+	echo "<div class='update-nag notice notice-warning inline'>$msg</div>";
 }
 
-// Called directly from dashboard
+/**
+ * Displays WordPress version and active theme in the 'At a Glance' dashboard widget.
+ *
+ * @since 2.5.0
+ */
 function update_right_now_message() {
 	$theme_name = wp_get_theme();
 	if ( current_user_can( 'switch_themes' ) ) {
@@ -300,12 +338,17 @@
 	if ( current_user_can( 'update_core' ) ) {
 		$cur = get_preferred_from_update_core();
 
-		if ( isset( $cur->response ) && $cur->response == 'upgrade' ) {
-			$msg .= '<a href="' . network_admin_url( 'update-core.php' ) . '" class="button" aria-describedby="wp-version">' . sprintf( __( 'Update to %s' ), $cur->current ? $cur->current : __( 'Latest' ) ) . '</a> ';
+		if ( isset( $cur->response ) && 'upgrade' === $cur->response ) {
+			$msg .= sprintf(
+				'<a href="%s" class="button" aria-describedby="wp-version">%s</a> ',
+				network_admin_url( 'update-core.php' ),
+				/* translators: %s: WordPress version number, or 'Latest' string. */
+				sprintf( __( 'Update to %s' ), $cur->current ? $cur->current : __( 'Latest' ) )
+			);
 		}
 	}
 
-	/* translators: 1: version number, 2: theme name */
+	/* translators: 1: Version number, 2: Theme name. */
 	$content = __( 'WordPress %1$s running %2$s theme.' );
 
 	/**
@@ -355,7 +398,7 @@
 	if ( isset( $plugins->response ) && is_array( $plugins->response ) ) {
 		$plugins = array_keys( $plugins->response );
 		foreach ( $plugins as $plugin_file ) {
-			add_action( "after_plugin_row_$plugin_file", 'wp_plugin_update_row', 10, 2 );
+			add_action( "after_plugin_row_{$plugin_file}", 'wp_plugin_update_row', 10, 2 );
 		}
 	}
 }
@@ -363,9 +406,11 @@
 /**
  * Displays update information for a plugin.
  *
+ * @since 2.3.0
+ *
  * @param string $file        Plugin basename.
  * @param array  $plugin_data Plugin information.
- * @return false|void
+ * @return void|false
  */
 function wp_plugin_update_row( $file, $plugin_data ) {
 	$current = get_site_transient( 'update_plugins' );
@@ -391,7 +436,12 @@
 	$details_url = self_admin_url( 'plugin-install.php?tab=plugin-information&plugin=' . $response->slug . '&section=changelog&TB_iframe=true&width=600&height=800' );
 
 	/** @var WP_Plugins_List_Table $wp_list_table */
-	$wp_list_table = _get_list_table( 'WP_Plugins_List_Table' );
+	$wp_list_table = _get_list_table(
+		'WP_Plugins_List_Table',
+		array(
+			'screen' => get_current_screen(),
+		)
+	);
 
 	if ( is_network_admin() || ! is_multisite() ) {
 		if ( is_network_admin() ) {
@@ -404,63 +454,73 @@
 		$compatible_php = is_php_version_compatible( $requires_php );
 		$notice_type    = $compatible_php ? 'notice-warning' : 'notice-error';
 
-		echo '<tr class="plugin-update-tr' . $active_class . '" id="' . esc_attr( $response->slug . '-update' ) . '" data-slug="' . esc_attr( $response->slug ) . '" data-plugin="' . esc_attr( $file ) . '"><td colspan="' . esc_attr( $wp_list_table->get_column_count() ) . '" class="plugin-update colspanchange"><div class="update-message notice inline ' . $notice_type . ' notice-alt"><p>';
+		printf(
+			'<tr class="plugin-update-tr%s" id="%s" data-slug="%s" data-plugin="%s">' .
+			'<td colspan="%s" class="plugin-update colspanchange">' .
+			'<div class="update-message notice inline %s notice-alt"><p>',
+			$active_class,
+			esc_attr( $response->slug . '-update' ),
+			esc_attr( $response->slug ),
+			esc_attr( $file ),
+			esc_attr( $wp_list_table->get_column_count() ),
+			$notice_type
+		);
 
 		if ( ! current_user_can( 'update_plugins' ) ) {
-			/* translators: 1: plugin name, 2: details URL, 3: additional link attributes, 4: version number */
 			printf(
+				/* translators: 1: Plugin name, 2: Details URL, 3: Additional link attributes, 4: Version number. */
 				__( 'There is a new version of %1$s available. <a href="%2$s" %3$s>View version %4$s details</a>.' ),
 				$plugin_name,
 				esc_url( $details_url ),
 				sprintf(
 					'class="thickbox open-plugin-details-modal" aria-label="%s"',
-					/* translators: 1: plugin name, 2: version number */
+					/* translators: 1: Plugin name, 2: Version number. */
 					esc_attr( sprintf( __( 'View %1$s version %2$s details' ), $plugin_name, $response->new_version ) )
 				),
 				esc_attr( $response->new_version )
 			);
 		} elseif ( empty( $response->package ) ) {
-			/* translators: 1: plugin name, 2: details URL, 3: additional link attributes, 4: version number */
 			printf(
+				/* translators: 1: Plugin name, 2: Details URL, 3: Additional link attributes, 4: Version number. */
 				__( 'There is a new version of %1$s available. <a href="%2$s" %3$s>View version %4$s details</a>. <em>Automatic update is unavailable for this plugin.</em>' ),
 				$plugin_name,
 				esc_url( $details_url ),
 				sprintf(
 					'class="thickbox open-plugin-details-modal" aria-label="%s"',
-					/* translators: 1: plugin name, 2: version number */
+					/* translators: 1: Plugin name, 2: Version number. */
 					esc_attr( sprintf( __( 'View %1$s version %2$s details' ), $plugin_name, $response->new_version ) )
 				),
 				esc_attr( $response->new_version )
 			);
 		} else {
 			if ( $compatible_php ) {
-				/* translators: 1: plugin name, 2: details URL, 3: additional link attributes, 4: version number, 5: update URL, 6: additional link attributes */
 				printf(
+					/* translators: 1: Plugin name, 2: Details URL, 3: Additional link attributes, 4: Version number, 5: Update URL, 6: Additional link attributes. */
 					__( 'There is a new version of %1$s available. <a href="%2$s" %3$s>View version %4$s details</a> or <a href="%5$s" %6$s>update now</a>.' ),
 					$plugin_name,
 					esc_url( $details_url ),
 					sprintf(
 						'class="thickbox open-plugin-details-modal" aria-label="%s"',
-						/* translators: 1: plugin name, 2: version number */
+						/* translators: 1: Plugin name, 2: Version number. */
 						esc_attr( sprintf( __( 'View %1$s version %2$s details' ), $plugin_name, $response->new_version ) )
 					),
 					esc_attr( $response->new_version ),
 					wp_nonce_url( self_admin_url( 'update.php?action=upgrade-plugin&plugin=' ) . $file, 'upgrade-plugin_' . $file ),
 					sprintf(
 						'class="update-link" aria-label="%s"',
-						/* translators: %s: plugin name */
-						esc_attr( sprintf( __( 'Update %s now' ), $plugin_name ) )
+						/* translators: %s: Plugin name. */
+						esc_attr( sprintf( _x( 'Update %s now', 'plugin' ), $plugin_name ) )
 					)
 				);
 			} else {
-				/* translators: 1: plugin name, 2: details URL, 3: additional link attributes, 4: version number 5: Update PHP page URL */
 				printf(
+					/* translators: 1: Plugin name, 2: Details URL, 3: Additional link attributes, 4: Version number 5: URL to Update PHP page. */
 					__( 'There is a new version of %1$s available, but it doesn&#8217;t work with your version of PHP. <a href="%2$s" %3$s>View version %4$s details</a> or <a href="%5$s">learn more about updating PHP</a>.' ),
 					$plugin_name,
 					esc_url( $details_url ),
 					sprintf(
 						'class="thickbox open-plugin-details-modal" aria-label="%s"',
-						/* translators: 1: plugin name, 2: version number */
+						/* translators: 1: Plugin name, 2: Version number. */
 						esc_attr( sprintf( __( 'View %1$s version %2$s details' ), $plugin_name, $response->new_version ) )
 					),
 					esc_attr( $response->new_version ),
@@ -505,13 +565,15 @@
 		 *     @type string $package     Plugin update package URL.
 		 * }
 		 */
-		do_action( "in_plugin_update_message-{$file}", $plugin_data, $response );
+		do_action( "in_plugin_update_message-{$file}", $plugin_data, $response ); // phpcs:ignore WordPress.NamingConventions.ValidHookName.UseUnderscores
 
 		echo '</p></div></td></tr>';
 	}
 }
 
 /**
+ * @since 2.9.0
+ *
  * @return array
  */
 function get_theme_updates() {
@@ -543,7 +605,7 @@
 		$themes = array_keys( $themes->response );
 
 		foreach ( $themes as $theme ) {
-			add_action( "after_theme_row_$theme", 'wp_theme_update_row', 10, 2 );
+			add_action( "after_theme_row_{$theme}", 'wp_theme_update_row', 10, 2 );
 		}
 	}
 }
@@ -551,9 +613,11 @@
 /**
  * Displays update information for a theme.
  *
+ * @since 3.1.0
+ *
  * @param string   $theme_key Theme stylesheet.
  * @param WP_Theme $theme     Theme object.
- * @return false|void
+ * @return void|false
  */
 function wp_theme_update_row( $theme_key, $theme ) {
 	$current = get_site_transient( 'update_themes' );
@@ -578,52 +642,126 @@
 
 	$active = $theme->is_allowed( 'network' ) ? ' active' : '';
 
-	echo '<tr class="plugin-update-tr' . $active . '" id="' . esc_attr( $theme->get_stylesheet() . '-update' ) . '" data-slug="' . esc_attr( $theme->get_stylesheet() ) . '"><td colspan="' . $wp_list_table->get_column_count() . '" class="plugin-update colspanchange"><div class="update-message notice inline notice-warning notice-alt"><p>';
-	if ( ! current_user_can( 'update_themes' ) ) {
-		/* translators: 1: theme name, 2: details URL, 3: additional link attributes, 4: version number */
-		printf(
-			__( 'There is a new version of %1$s available. <a href="%2$s" %3$s>View version %4$s details</a>.' ),
-			$theme['Name'],
-			esc_url( $details_url ),
-			sprintf(
-				'class="thickbox open-plugin-details-modal" aria-label="%s"',
-				/* translators: 1: theme name, 2: version number */
-				esc_attr( sprintf( __( 'View %1$s version %2$s details' ), $theme['Name'], $response['new_version'] ) )
-			),
-			$response['new_version']
-		);
-	} elseif ( empty( $response['package'] ) ) {
-		/* translators: 1: theme name, 2: details URL, 3: additional link attributes, 4: version number */
-		printf(
-			__( 'There is a new version of %1$s available. <a href="%2$s" %3$s>View version %4$s details</a>. <em>Automatic update is unavailable for this theme.</em>' ),
-			$theme['Name'],
-			esc_url( $details_url ),
-			sprintf(
-				'class="thickbox open-plugin-details-modal" aria-label="%s"',
-				/* translators: 1: theme name, 2: version number */
-				esc_attr( sprintf( __( 'View %1$s version %2$s details' ), $theme['Name'], $response['new_version'] ) )
-			),
-			$response['new_version']
-		);
+	$requires_wp  = isset( $response['requires'] ) ? $response['requires'] : null;
+	$requires_php = isset( $response['requires_php'] ) ? $response['requires_php'] : null;
+
+	$compatible_wp  = is_wp_version_compatible( $requires_wp );
+	$compatible_php = is_php_version_compatible( $requires_php );
+
+	printf(
+		'<tr class="plugin-update-tr%s" id="%s" data-slug="%s">' .
+		'<td colspan="%s" class="plugin-update colspanchange">' .
+		'<div class="update-message notice inline notice-warning notice-alt"><p>',
+		$active,
+		esc_attr( $theme->get_stylesheet() . '-update' ),
+		esc_attr( $theme->get_stylesheet() ),
+		$wp_list_table->get_column_count()
+	);
+
+	if ( $compatible_wp && $compatible_php ) {
+		if ( ! current_user_can( 'update_themes' ) ) {
+			printf(
+				/* translators: 1: Theme name, 2: Details URL, 3: Additional link attributes, 4: Version number. */
+				__( 'There is a new version of %1$s available. <a href="%2$s" %3$s>View version %4$s details</a>.' ),
+				$theme['Name'],
+				esc_url( $details_url ),
+				sprintf(
+					'class="thickbox open-plugin-details-modal" aria-label="%s"',
+					/* translators: 1: Theme name, 2: Version number. */
+					esc_attr( sprintf( __( 'View %1$s version %2$s details' ), $theme['Name'], $response['new_version'] ) )
+				),
+				$response['new_version']
+			);
+		} elseif ( empty( $response['package'] ) ) {
+			printf(
+				/* translators: 1: Theme name, 2: Details URL, 3: Additional link attributes, 4: Version number. */
+				__( 'There is a new version of %1$s available. <a href="%2$s" %3$s>View version %4$s details</a>. <em>Automatic update is unavailable for this theme.</em>' ),
+				$theme['Name'],
+				esc_url( $details_url ),
+				sprintf(
+					'class="thickbox open-plugin-details-modal" aria-label="%s"',
+					/* translators: 1: Theme name, 2: Version number. */
+					esc_attr( sprintf( __( 'View %1$s version %2$s details' ), $theme['Name'], $response['new_version'] ) )
+				),
+				$response['new_version']
+			);
+		} else {
+			printf(
+				/* translators: 1: Theme name, 2: Details URL, 3: Additional link attributes, 4: Version number, 5: Update URL, 6: Additional link attributes. */
+				__( 'There is a new version of %1$s available. <a href="%2$s" %3$s>View version %4$s details</a> or <a href="%5$s" %6$s>update now</a>.' ),
+				$theme['Name'],
+				esc_url( $details_url ),
+				sprintf(
+					'class="thickbox open-plugin-details-modal" aria-label="%s"',
+					/* translators: 1: Theme name, 2: Version number. */
+					esc_attr( sprintf( __( 'View %1$s version %2$s details' ), $theme['Name'], $response['new_version'] ) )
+				),
+				$response['new_version'],
+				wp_nonce_url( self_admin_url( 'update.php?action=upgrade-theme&theme=' ) . $theme_key, 'upgrade-theme_' . $theme_key ),
+				sprintf(
+					'class="update-link" aria-label="%s"',
+					/* translators: %s: Theme name. */
+					esc_attr( sprintf( _x( 'Update %s now', 'theme' ), $theme['Name'] ) )
+				)
+			);
+		}
 	} else {
-		/* translators: 1: theme name, 2: details URL, 3: additional link attributes, 4: version number, 5: update URL, 6: additional link attributes */
-		printf(
-			__( 'There is a new version of %1$s available. <a href="%2$s" %3$s>View version %4$s details</a> or <a href="%5$s" %6$s>update now</a>.' ),
-			$theme['Name'],
-			esc_url( $details_url ),
-			sprintf(
-				'class="thickbox open-plugin-details-modal" aria-label="%s"',
-				/* translators: 1: theme name, 2: version number */
-				esc_attr( sprintf( __( 'View %1$s version %2$s details' ), $theme['Name'], $response['new_version'] ) )
-			),
-			$response['new_version'],
-			wp_nonce_url( self_admin_url( 'update.php?action=upgrade-theme&theme=' ) . $theme_key, 'upgrade-theme_' . $theme_key ),
-			sprintf(
-				'class="update-link" aria-label="%s"',
-				/* translators: %s: theme name */
-				esc_attr( sprintf( __( 'Update %s now' ), $theme['Name'] ) )
-			)
-		);
+		if ( ! $compatible_wp && ! $compatible_php ) {
+			printf(
+				/* translators: %s: Theme name. */
+				__( 'There is a new version of %s available, but it doesn&#8217;t work with your versions of WordPress and PHP.' ),
+				$theme['Name']
+			);
+			if ( current_user_can( 'update_core' ) && current_user_can( 'update_php' ) ) {
+				printf(
+					/* translators: 1: URL to WordPress Updates screen, 2: URL to Update PHP page. */
+					' ' . __( '<a href="%1$s">Please update WordPress</a>, and then <a href="%2$s">learn more about updating PHP</a>.' ),
+					self_admin_url( 'update-core.php' ),
+					esc_url( wp_get_update_php_url() )
+				);
+				wp_update_php_annotation( '</p><p><em>', '</em>' );
+			} elseif ( current_user_can( 'update_core' ) ) {
+				printf(
+					/* translators: %s: URL to WordPress Updates screen. */
+					' ' . __( '<a href="%s">Please update WordPress</a>.' ),
+					self_admin_url( 'update-core.php' )
+				);
+			} elseif ( current_user_can( 'update_php' ) ) {
+				printf(
+					/* translators: %s: URL to Update PHP page. */
+					' ' . __( '<a href="%s">Learn more about updating PHP</a>.' ),
+					esc_url( wp_get_update_php_url() )
+				);
+				wp_update_php_annotation( '</p><p><em>', '</em>' );
+			}
+		} elseif ( ! $compatible_wp ) {
+			printf(
+				/* translators: %s: Theme name. */
+				__( 'There is a new version of %s available, but it doesn&#8217;t work with your version of WordPress.' ),
+				$theme['Name']
+			);
+			if ( current_user_can( 'update_core' ) ) {
+				printf(
+					/* translators: %s: URL to WordPress Updates screen. */
+					' ' . __( '<a href="%s">Please update WordPress</a>.' ),
+					self_admin_url( 'update-core.php' )
+				);
+			}
+		} elseif ( ! $compatible_php ) {
+			printf(
+				/* translators: %s: Theme name. */
+				__( 'There is a new version of %s available, but it doesn&#8217;t work with your version of PHP.' ),
+				$theme['Name']
+			);
+			if ( current_user_can( 'update_php' ) ) {
+				printf(
+					/* translators: %s: URL to Update PHP page. */
+					' ' . __( '<a href="%s">Learn more about updating PHP</a>.' ),
+					esc_url( wp_get_update_php_url() )
+				);
+				wp_update_php_annotation( '</p><p><em>', '</em>' );
+			}
+		}
 	}
 
 	/**
@@ -644,17 +782,20 @@
 	 *     @type string $package     Theme update package URL.
 	 * }
 	 */
-	do_action( "in_theme_update_message-{$theme_key}", $theme, $response );
+	do_action( "in_theme_update_message-{$theme_key}", $theme, $response ); // phpcs:ignore WordPress.NamingConventions.ValidHookName.UseUnderscores
 
 	echo '</p></div></td></tr>';
 }
 
 /**
+ * @since 2.7.0
+ *
  * @global int $upgrading
- * @return false|void
+ * @return void|false
  */
 function maintenance_nag() {
-	include( ABSPATH . WPINC . '/version.php' ); // include an unmodified $wp_version
+	// Include an unmodified $wp_version.
+	require ABSPATH . WPINC . '/version.php';
 	global $upgrading;
 	$nag = isset( $upgrading );
 	if ( ! $nag ) {
@@ -670,7 +811,7 @@
 		 * This flag is cleared whenever a successful update occurs using Core_Upgrader.
 		 */
 		$comparison = ! empty( $failed['critical'] ) ? '>=' : '>';
-		if ( version_compare( $failed['attempted'], $wp_version, $comparison ) ) {
+		if ( isset( $failed['attempted'] ) && version_compare( $failed['attempted'], $wp_version, $comparison ) ) {
 			$nag = true;
 		}
 	}
@@ -680,12 +821,16 @@
 	}
 
 	if ( current_user_can( 'update_core' ) ) {
-		$msg = sprintf( __( 'An automated WordPress update has failed to complete - <a href="%s">please attempt the update again now</a>.' ), 'update-core.php' );
+		$msg = sprintf(
+			/* translators: %s: URL to WordPress Updates screen. */
+			__( 'An automated WordPress update has failed to complete - <a href="%s">please attempt the update again now</a>.' ),
+			'update-core.php'
+		);
 	} else {
 		$msg = __( 'An automated WordPress update has failed to complete! Please notify the site administrator.' );
 	}
 
-	echo "<div class='update-nag'>$msg</div>";
+	echo "<div class='update-nag notice notice-warning inline'>$msg</div>";
 }
 
 /**
@@ -716,24 +861,24 @@
 					<# if ( 1 === data.successes ) { #>
 						<# if ( 'plugin' === data.type ) { #>
 							<?php
-							/* translators: %s: Number of plugins */
+							/* translators: %s: Number of plugins. */
 							printf( __( '%s plugin successfully updated.' ), '{{ data.successes }}' );
 							?>
 						<# } else { #>
 							<?php
-							/* translators: %s: Number of themes */
+							/* translators: %s: Number of themes. */
 							printf( __( '%s theme successfully updated.' ), '{{ data.successes }}' );
 							?>
 						<# } #>
 					<# } else { #>
 						<# if ( 'plugin' === data.type ) { #>
 							<?php
-							/* translators: %s: Number of plugins */
+							/* translators: %s: Number of plugins. */
 							printf( __( '%s plugins successfully updated.' ), '{{ data.successes }}' );
 							?>
 						<# } else { #>
 							<?php
-							/* translators: %s: Number of themes */
+							/* translators: %s: Number of themes. */
 							printf( __( '%s themes successfully updated.' ), '{{ data.successes }}' );
 							?>
 						<# } #>
@@ -743,12 +888,12 @@
 					<button class="button-link bulk-action-errors-collapsed" aria-expanded="false">
 						<# if ( 1 === data.errors ) { #>
 							<?php
-							/* translators: %s: Number of failed updates */
+							/* translators: %s: Number of failed updates. */
 							printf( __( '%s update failed.' ), '{{ data.errors }}' );
 							?>
 						<# } else { #>
 							<?php
-							/* translators: %s: Number of failed updates */
+							/* translators: %s: Number of failed updates. */
 							printf( __( '%s updates failed.' ), '{{ data.errors }}' );
 							?>
 						<# } #>
@@ -811,7 +956,7 @@
 				<# if ( data.plugin ) { #>
 					<?php
 					printf(
-						/* translators: %s: Plugin name */
+						/* translators: %s: Plugin name. */
 						_x( '%s was successfully deleted.', 'plugin' ),
 						'<strong>{{{ data.name }}}</strong>'
 					);
@@ -819,7 +964,7 @@
 				<# } else { #>
 					<?php
 					printf(
-						/* translators: %s: Theme name */
+						/* translators: %s: Theme name. */
 						_x( '%s was successfully deleted.', 'theme' ),
 						'<strong>{{{ data.name }}}</strong>'
 					);
@@ -850,7 +995,7 @@
 		<p>
 			<?php
 			printf(
-				/* translators: %s: Recovery Mode exit link */
+				/* translators: %s: Recovery Mode exit link. */
 				__( 'You are in recovery mode. This means there may be an error with a theme or plugin. To exit recovery mode, log out or use the Exit button. <a href="%s">Exit Recovery Mode</a>' ),
 				esc_url( $url )
 			);
@@ -859,3 +1004,80 @@
 	</div>
 	<?php
 }
+
+/**
+ * Checks whether auto-updates are enabled.
+ *
+ * @since 5.5.0
+ *
+ * @param string $type The type of update being checked: 'theme' or 'plugin'.
+ * @return bool True if auto-updates are enabled for `$type`, false otherwise.
+ */
+function wp_is_auto_update_enabled_for_type( $type ) {
+	if ( ! class_exists( 'WP_Automatic_Updater' ) ) {
+		require_once ABSPATH . 'wp-admin/includes/class-wp-automatic-updater.php';
+	}
+
+	$updater = new WP_Automatic_Updater();
+	$enabled = ! $updater->is_disabled();
+
+	switch ( $type ) {
+		case 'plugin':
+			/**
+			 * Filters whether plugins auto-update is enabled.
+			 *
+			 * @since 5.5.0
+			 *
+			 * @param bool $enabled True if plugins auto-update is enabled, false otherwise.
+			 */
+			return apply_filters( 'plugins_auto_update_enabled', $enabled );
+		case 'theme':
+			/**
+			 * Filters whether themes auto-update is enabled.
+			 *
+			 * @since 5.5.0
+			 *
+			 * @param bool $enabled True if themes auto-update is enabled, false otherwise.
+			 */
+			return apply_filters( 'themes_auto_update_enabled', $enabled );
+	}
+
+	return false;
+}
+
+/**
+ * Determines the appropriate auto-update message to be displayed.
+ *
+ * @since 5.5.0
+ *
+ * @return string The update message to be shown.
+ */
+function wp_get_auto_update_message() {
+	$next_update_time = wp_next_scheduled( 'wp_version_check' );
+
+	// Check if the event exists.
+	if ( false === $next_update_time ) {
+		$message = __( 'Automatic update not scheduled. There may be a problem with WP-Cron.' );
+	} else {
+		$time_to_next_update = human_time_diff( intval( $next_update_time ) );
+
+		// See if cron is overdue.
+		$overdue = ( time() - $next_update_time ) > 0;
+
+		if ( $overdue ) {
+			$message = sprintf(
+				/* translators: %s: Duration that WP-Cron has been overdue. */
+				__( 'Automatic update overdue by %s. There may be a problem with WP-Cron.' ),
+				$time_to_next_update
+			);
+		} else {
+			$message = sprintf(
+				/* translators: %s: Time until the next update. */
+				__( 'Automatic update scheduled in %s.' ),
+				$time_to_next_update
+			);
+		}
+	}
+
+	return $message;
+}