WP_Site_Health::get_test_theme_version() WordPress Method

	public function get_test_theme_version() {
		$result = array(
			'label'       => __( 'Your themes are all up to date' ),
			'status'      => 'good',
			'badge'       => array(
				'label' => __( 'Security' ),
				'color' => 'blue',
			),
			'description' => sprintf(
				'<p>%s</p>',
				__( 'Themes add your site&#8217;s look and feel. It&#8217;s important to keep them up to date, to stay consistent with your brand and keep your site secure.' )
			),
			'actions'     => sprintf(
				'<p><a href="%s">%s</a></p>',
				esc_url( admin_url( 'themes.php' ) ),
				__( 'Manage your themes' )
			),
			'test'        => 'theme_version',
		);

		$theme_updates = get_theme_updates();

		$themes_total        = 0;
		$themes_need_updates = 0;
		$themes_inactive     = 0;

		// This value is changed during processing to determine how many themes are considered a reasonable amount.
		$allowed_theme_count = 1;

		$has_default_theme   = false;
		$has_unused_themes   = false;
		$show_unused_themes  = true;
		$using_default_theme = false;

		// Populate a list of all themes available in the install.
		$all_themes   = wp_get_themes();
		$active_theme = wp_get_theme();

		// If WP_DEFAULT_THEME doesn't exist, fall back to the latest core default theme.
		$default_theme = wp_get_theme( WP_DEFAULT_THEME );
		if ( ! $default_theme->exists() ) {
			$default_theme = WP_Theme::get_core_default_theme();
		}

		if ( $default_theme ) {
			$has_default_theme = true;

			if (
				$active_theme->get_stylesheet() === $default_theme->get_stylesheet()
			||
				is_child_theme() && $active_theme->get_template() === $default_theme->get_template()
			) {
				$using_default_theme = true;
			}
		}

		foreach ( $all_themes as $theme_slug => $theme ) {
			$themes_total++;

			if ( array_key_exists( $theme_slug, $theme_updates ) ) {
				$themes_need_updates++;
			}
		}

		// If this is a child theme, increase the allowed theme count by one, to account for the parent.
		if ( is_child_theme() ) {
			$allowed_theme_count++;
		}

		// If there's a default theme installed and not in use, we count that as allowed as well.
		if ( $has_default_theme && ! $using_default_theme ) {
			$allowed_theme_count++;
		}

		if ( $themes_total > $allowed_theme_count ) {
			$has_unused_themes = true;
			$themes_inactive   = ( $themes_total - $allowed_theme_count );
		}

		// Check if any themes need to be updated.
		if ( $themes_need_updates > 0 ) {
			$result['status'] = 'critical';

			$result['label'] = __( 'You have themes waiting to be updated' );

			$result['description'] .= sprintf(
				'<p>%s</p>',
				sprintf(
					/* translators: %d: The number of outdated themes. */
					_n(
						'Your site has %d theme waiting to be updated.',
						'Your site has %d themes waiting to be updated.',
						$themes_need_updates
					),
					$themes_need_updates
				)
			);
		} else {
			// Give positive feedback about the site being good about keeping things up to date.
			if ( 1 === $themes_total ) {
				$result['description'] .= sprintf(
					'<p>%s</p>',
					__( 'Your site has 1 installed theme, and it is up to date.' )
				);
			} else {
				$result['description'] .= sprintf(
					'<p>%s</p>',
					sprintf(
						/* translators: %d: The number of themes. */
						_n(
							'Your site has %d installed theme, and it is up to date.',
							'Your site has %d installed themes, and they are all up to date.',
							$themes_total
						),
						$themes_total
					)
				);
			}
		}

		if ( $has_unused_themes && $show_unused_themes && ! is_multisite() ) {

			// This is a child theme, so we want to be a bit more explicit in our messages.
			if ( $active_theme->parent() ) {
				// Recommend removing inactive themes, except a default theme, your current one, and the parent theme.
				$result['status'] = 'recommended';

				$result['label'] = __( 'You should remove inactive themes' );

				if ( $using_default_theme ) {
					$result['description'] .= sprintf(
						'<p>%s %s</p>',
						sprintf(
							/* translators: %d: The number of inactive themes. */
							_n(
								'Your site has %d inactive theme.',
								'Your site has %d inactive themes.',
								$themes_inactive
							),
							$themes_inactive
						),
						sprintf(
							/* translators: 1: The currently active theme. 2: The active theme's parent theme. */
							__( 'To enhance your site&#8217;s security, you should consider removing any themes you are not using. You should keep your active theme, %1$s, and %2$s, its parent theme.' ),
							$active_theme->name,
							$active_theme->parent()->name
						)
					);
				} else {
					$result['description'] .= sprintf(
						'<p>%s %s</p>',
						sprintf(
							/* translators: %d: The number of inactive themes. */
							_n(
								'Your site has %d inactive theme.',
								'Your site has %d inactive themes.',
								$themes_inactive
							),
							$themes_inactive
						),
						sprintf(
							/* translators: 1: The default theme for WordPress. 2: The currently active theme. 3: The active theme's parent theme. */
							__( 'To enhance your site&#8217;s security, you should consider removing any themes you are not using. You should keep %1$s, the default WordPress theme, %2$s, your active theme, and %3$s, its parent theme.' ),
							$default_theme ? $default_theme->name : WP_DEFAULT_THEME,
							$active_theme->name,
							$active_theme->parent()->name
						)
					);
				}
			} else {
				// Recommend removing all inactive themes.
				$result['status'] = 'recommended';

				$result['label'] = __( 'You should remove inactive themes' );

				if ( $using_default_theme ) {
					$result['description'] .= sprintf(
						'<p>%s %s</p>',
						sprintf(
							/* translators: 1: The amount of inactive themes. 2: The currently active theme. */
							_n(
								'Your site has %1$d inactive theme, other than %2$s, your active theme.',
								'Your site has %1$d inactive themes, other than %2$s, your active theme.',
								$themes_inactive
							),
							$themes_inactive,
							$active_theme->name
						),
						__( 'You should consider removing any unused themes to enhance your site&#8217;s security.' )
					);
				} else {
					$result['description'] .= sprintf(
						'<p>%s %s</p>',
						sprintf(
							/* translators: 1: The amount of inactive themes. 2: The default theme for WordPress. 3: The currently active theme. */
							_n(
								'Your site has %1$d inactive theme, other than %2$s, the default WordPress theme, and %3$s, your active theme.',
								'Your site has %1$d inactive themes, other than %2$s, the default WordPress theme, and %3$s, your active theme.',
								$themes_inactive
							),
							$themes_inactive,
							$default_theme ? $default_theme->name : WP_DEFAULT_THEME,
							$active_theme->name
						),
						__( 'You should consider removing any unused themes to enhance your site&#8217;s security.' )
					);
				}
			}
		}

		// If no default Twenty* theme exists.
		if ( ! $has_default_theme ) {
			$result['status'] = 'recommended';

			$result['label'] = __( 'Have a default theme available' );

			$result['description'] .= sprintf(
				'<p>%s</p>',
				__( 'Your site does not have any default theme. Default themes are used by WordPress automatically if anything is wrong with your chosen theme.' )
			);
		}

		return $result;
	}