[params] Return empty object

Author: jamesgpearce

src/@types/queries/docs.js

@@ -1872,8 +1872,8 @@
    * The getParamValues method returns all the param values currently set for a
    * parameterized query.
    * @param queryId The Id of the query to get the params for.
-   * @returns An object containing all param Ids and their values, or
-   * `undefined` if the query doesn't exist.
+   * @returns An object containing all param Ids and their values, or an empty
+   * object if the query doesn't exist.
    * @example
    * This example creates a parameterized query and retrieves its param values.
    *

src/@types/queries/index.d.ts

@@ -310,7 +310,7 @@ export interface Queries {
   delQueryDefinition(queryId: Id): Queries;
 
   /// Queries.getParamValues
-  getParamValues(queryId: Id): ParamValues | undefined;
+  getParamValues(queryId: Id): ParamValues;
 
   /// Queries.getParamValue
   getParamValue(queryId: Id, paramId: Id): ParamValue | undefined;

src/@types/queries/with-schemas/index.d.ts

@@ -392,7 +392,7 @@ export interface Queries<in out Schemas extends OptionalSchemas> {
   delQueryDefinition(queryId: Id): Queries<Schemas>;
 
   /// Queries.getParamValues
-  getParamValues(queryId: Id): ParamValues | undefined;
+  getParamValues(queryId: Id): ParamValues;
 
   /// Queries.getParamValue
   getParamValue(queryId: Id, paramId: Id): ParamValue | undefined;

test/unit/core/other/queries.test.ts

@@ -4784,7 +4784,7 @@ describe('Parameterized', () => {
       queries.setParamValue('q1', 'p2', 'even');
       expect(queries.getParamValues('q1')).toEqual({p2: 'even', p3: 5});
 
-      expect(queries.getParamValues('nonexistent')).toBeUndefined();
+      expect(queries.getParamValues('nonexistent')).toEqual({});
     });
 
     test('getParamValue', () => {