core-api: switch to deprecating routing types rather than removing

.changeset/red-worms-fold.md

@@ -1,5 +1,9 @@
 ---
-'@backstage/core-api': minor
+'@backstage/core-api': patch
 ---
 
-Remove exported `ConcreteRoute`, `MutableRouteRef`, `AbsoluteRouteRef` types, and add as of yet unused `params` option to `createRouteRef`.
+Deprecated the `ConcreteRoute`, `MutableRouteRef`, `AbsoluteRouteRef` types and added a new `RouteRef` type as replacement.
+
+Deprecated and disabled the `createSubRoute` method of `AbsoluteRouteRef`.
+
+Add an as of yet unused `params` option to `createRouteRef`.

packages/core-api/src/routing/RouteRef.ts

@@ -32,8 +32,14 @@ export class AbsoluteRouteRef<Params extends { [param in string]: string }> {
     return this.config.title;
   }
 
-  get P(): Params {
-    throw new Error("Don't call me maybe");
+  /**
+   * This function should not be used, create a separate RouteRef instead
+   * @deprecated
+   */
+  createSubRoute(): any {
+    throw new Error(
+      'This method should not be called, create a separate RouteRef instead',
+    );
   }
 
   toString() {

packages/core-api/src/routing/index.ts

@@ -14,5 +14,11 @@
  * limitations under the License.
  */
 
-export type { RouteRef, RouteRefConfig } from './types';
+export type {
+  RouteRef,
+  RouteRefConfig,
+  AbsoluteRouteRef,
+  ConcreteRoute,
+  MutableRouteRef,
+} from './types';
 export { createRouteRef } from './RouteRef';

packages/core-api/src/routing/types.ts

@@ -16,16 +16,39 @@
 
 import { IconComponent } from '../icons';
 
+// @ts-ignore, we're just embedding the Params type for usage in other places
 export type RouteRef<Params extends { [param in string]: string } = {}> = {
   // TODO(Rugvip): Remove path, look up via registry instead
   path: string;
   icon?: IconComponent;
   title: string;
-  P: Params;
+  /**
+   * This function should not be used, create a separate RouteRef instead
+   * @deprecated
+   */
+  createSubRoute(): any;
 };
 
 export type AnyRouteRef = RouteRef<any>;
 
+/**
+ * This type should not be used
+ * @deprecated
+ */
+export type ConcreteRoute = {};
+
+/**
+ * This type should not be used, use RouteRef instead
+ * @deprecated
+ */
+export type AbsoluteRouteRef = RouteRef<{}>;
+
+/**
+ * This type should not be used, use RouteRef instead
+ * @deprecated
+ */
+export type MutableRouteRef = RouteRef<{}>;
+
 export type RouteRefConfig<Params extends { [param in string]: string }> = {
   params?: Array<keyof Params>;
   path: string;