Allow setting a message to be displayed if the module can't be loaded

aristath · aristath · commit d75d91c74c94 · 2022-11-09T08:30:27.000+02:00
diff --git a/admin/load.php b/admin/load.php
@@ -156,11 +156,16 @@ function perflab_render_modules_page_field( $module_slug, $module_data, $module_
 				<input type="checkbox" id="<?php echo esc_attr( "{$base_id}_enabled" ); ?>" aria-describedby="<?php echo esc_attr( "{$base_id}_description" ); ?>" disabled>
 				<input type="hidden" name="<?php echo esc_attr( "{$base_name}[enabled]" ); ?>" value="<?php echo $enabled ? '1' : '0'; ?>">
 				<?php
+				$message = perflab_can_load_module( $module_slug, true );
+				if ( $message ) {
+					echo esc_html( $message );
+				} else {
 					printf(
 						/* translators: %s: module name */
 						__( '%s is already part of your WordPress version and therefore cannot be loaded as part of the plugin.', 'performance-lab' ),
 						esc_html( $module_data['name'] )
 					);
+				}
 				?>
 			<?php } ?>
 		</label>
diff --git a/load.php b/load.php
@@ -216,10 +216,14 @@ function perflab_render_generator() {
  *
  * @since 1.3.0
  *
- * @param string $module Slug of the module.
- * @return bool Whether the module can be loaded or not.
+ * @param string $module      Slug of the module.
+ * @param bool   $get_message Optional. Whether to return the message instead of a boolean. Default false.
+ *
+ * @return bool|string Whether the module can be loaded or not.
+ *                     If the module can't be loaded, it can return either `false`,
+ *                     or a string with the message to be shown to users when $get_message is `true`.
  */
-function perflab_can_load_module( $module ) {
+function perflab_can_load_module( $module, $get_message = false ) {
 	$module_load_file = PERFLAB_PLUGIN_DIR_PATH . 'modules/' . $module . '/can-load.php';
 
 	// If the `can-load.php` file does not exist, assume the module can be loaded.
@@ -236,7 +240,13 @@ function perflab_can_load_module( $module ) {
 	}
 
 	// Call the closure to determine whether the module can be loaded.
-	return (bool) $module();
+	$result = $module();
+
+	if ( false !== $result && true !== $result ) {
+		return $get_message ? $result : false;
+	}
+
+	return (bool) $result;
 }
 
 /**
diff --git a/modules/database/sqlite/can-load.php b/modules/database/sqlite/can-load.php
@@ -12,6 +12,17 @@
  * @since n.e.x.t
  */
 return function() {
-	$is_writable_wp_content_dir = wp_is_writable( WP_CONTENT_DIR );
-	return class_exists( 'SQLite3' ) && $is_writable_wp_content_dir;
+	if ( ! wp_is_writable( WP_CONTENT_DIR ) ) {
+		return sprintf(
+			/* translators: %s: WP_CONTENT_DIR */
+			__( 'The SQLite module cannot be activated because the %s directory is not writable.', 'performance-lab' ),
+			WP_CONTENT_DIR
+		);
+	}
+
+	if ( ! extension_loaded( 'sqlite3' ) || ! class_exists( 'SQLite3' ) ) {
+		return __( 'The SQLite module cannot be activated because the SQLite extension is not loaded.', 'performance-lab' );
+	}
+
+	return true;
 };
