add eslint to to ensure umb prefix on classes

src/Umbraco.Web.UI.Client/.eslintrc.json

@@ -44,6 +44,7 @@
 				"local-rules/enforce-element-suffix-on-element-class-name": "error",
 				"local-rules/prefer-umbraco-cms-imports": "error",
 				"local-rules/no-external-imports": "error",
+				"local-rules/umb-class-prefix": "error",
 				"@typescript-eslint/no-non-null-assertion": "off"
 			},
 			"settings": {

src/Umbraco.Web.UI.Client/eslint-local-rules.cjs

@@ -205,4 +205,31 @@ module.exports = {
 			};
 		},
 	},
+
+	/** @type {import('eslint').Rule.RuleModule} */
+	'umb-class-prefix': {
+		meta: {
+			type: 'problem',
+			docs: {
+				description: 'Ensure that all class declarations are prefixed with "Umb"',
+				category: 'Best Practices',
+				recommended: true,
+			},
+			schema: [],
+		},
+		create: function (context) {
+			function checkClassName(node) {
+				if (node.id && node.id.name && !node.id.name.startsWith('Umb')) {
+					context.report({
+						node: node.id,
+						message: 'Class declaration should be prefixed with "Umb"',
+					});
+				}
+			}
+
+			return {
+				ClassDeclaration: checkClassName,
+			};
+		},
+	},
 };