fix: Changed the evaluateInputHandlers function on Control to throw an error if more than one matching handlers are found

BREAKING CHANGE: Whenever a request is processed by a Control and evaluated with its defined handlers, if more than one handler matches are found, control throws an error with matching handlers.

Author: shreraju-amzn

src/utils/ControlUtils.ts

@@ -53,9 +53,9 @@ export async function evaluateInputHandlers(control: Control, input: ControlInpu
     }
 
     if (matches.length > 1) {
-        log.error(
-            `More than one handler matched. Handlers in a single control should be mutually exclusive. ` +
-                `Defaulting to the first. handlers: ${JSON.stringify(matches.map((x) => x.name))}`,
+        throw Error(
+            `More than one handler matched. Handlers in a single control should be mutually exclusive.` +
+                ` handlers: ${JSON.stringify(matches.map((x) => x.name))}`,
         );
     }
 

test/scenarios.spec.ts

@@ -312,31 +312,21 @@ suite('== Custom Handler function scenarios ==', () => {
         expect(dateControlState.state.value).eq('2020-01-01');
     });
 
-    test('Check conflicts in canHandle throws a error log', async () => {
+    test('Check conflicts in canHandle throws Error', async () => {
         const rootControl = new DateSelectorManager().createControlTree();
         const input = TestInput.of(
             ValueControlIntent.of(AmazonBuiltInSlotType.DATE, {
                 'AMAZON.DATE': '2018',
                 action: $.Action.Set,
             }),
         );
-        const spy = sinon.stub(DefaultLogger.prototype, 'error');
-        const result = new ControlResultBuilder(undefined!);
-        await rootControl.canHandle(input);
-        await rootControl.handle(input, result);
-
-        expect(
-            spy.calledOnceWith(
-                'More than one handler matched. Handlers in a single control should be mutually exclusive. Defaulting to the first. handlers: ["SetWithValue (built-in)","SetValue"]',
-            ),
-        ).eq(true);
-
-        spy.restore();
-
-        const dateControlState = findControlInTreeById(rootControl, 'dateControl');
-        expect(dateControlState.state.value).eq('2018');
-        expect(result.acts).length(1);
-        expect(result.acts[0]).instanceOf(ValueSetAct);
+        try {
+            await rootControl.canHandle(input);
+        } catch (e) {
+            expect(e.message).eq(
+                'More than one handler matched. Handlers in a single control should be mutually exclusive. handlers: ["SetWithValue (built-in)","SetValue"]',
+            );
+        }
     });
 });