Check that the callback for filtering payment methods is available and is a function before trying to run it (https://github.com/woocommerce/woocommerce-blocks/pull/7377)

* Check callback for payment method is available before trying to run it

* Check if callback is a function before trying to run it

* Update tests to ensure callbacks only run if they are registered

plugins/woocommerce-blocks/assets/js/blocks-registry/payment-methods/payment-method-config-helper.ts

@@ -50,6 +50,12 @@ export const canMakePaymentWithExtensions =
 
 			Object.entries( extensionsCallbacks ).forEach(
 				( [ namespace, callbacks ] ) => {
+					if (
+						! ( paymentMethodName in callbacks ) ||
+						typeof callbacks[ paymentMethodName ] !== 'function'
+					) {
+						return;
+					}
 					namespacedCallbacks[ namespace ] =
 						callbacks[ paymentMethodName ];
 				}

plugins/woocommerce-blocks/assets/js/blocks-registry/payment-methods/test/payment-method-config-helper.ts

@@ -88,6 +88,9 @@ describe( 'payment-method-config-helper', () => {
 				woopay: trueCallback,
 				// testpay: one callback errors, one returns true
 				testpay: throwsCallback,
+				// Used to check that only valid callbacks run in each namespace. It is not present in
+				// 'other-woocommerce-marketplace-extension'.
+				blocks_pay: trueCallback,
 			}
 		);
 		registerPaymentMethodExtensionCallbacks(
@@ -202,5 +205,14 @@ describe( 'payment-method-config-helper', () => {
 			expect( throwsCallback ).toHaveBeenCalledTimes( 1 );
 			expect( trueCallback ).toHaveBeenCalledTimes( 1 );
 		} );
+
+		it( 'Does not error when a callback for a payment method is in one namespace but not another', () => {
+			helpers.canMakePaymentWithExtensions(
+				() => true,
+				canMakePaymentExtensionsCallbacks,
+				'blocks_pay'
+			)( canMakePaymentArgument );
+			expect( console ).not.toHaveErrored();
+		} );
 	} );
 } );