Navigator Screen: warn if path doesn't follow a URL-like scheme

packages/components/CHANGELOG.md

@@ -12,6 +12,7 @@
 
 ### Enhancements
 
+-   `Navigator`: warn if a screen's `path` doesn't follow a URL-like scheme ([#65231](https://github.com/WordPress/gutenberg/pull/65231)).
 -   `Modal`: Decrease close button size and remove horizontal offset ([#65131](https://github.com/WordPress/gutenberg/pull/65131)).
 
 ### Internal

packages/components/src/navigator/navigator-screen/component.tsx

@@ -17,6 +17,7 @@ import {
 import { useMergeRefs } from '@wordpress/compose';
 import { isRTL as isRTLFn } from '@wordpress/i18n';
 import { escapeAttribute } from '@wordpress/escape-html';
+import warning from '@wordpress/warning';
 
 /**
  * Internal dependencies
@@ -33,6 +34,12 @@ function UnconnectedNavigatorScreen(
 	props: WordPressComponentProps< NavigatorScreenProps, 'div', false >,
 	forwardedRef: ForwardedRef< any >
 ) {
+	if ( ! /^\//.test( props.path ) ) {
+		warning(
+			'wp.components.NavigatorScreen: the `path` should follow a URL-like scheme; it should start with and be separated by the `/` character.'
+		);
+	}
+
 	const screenId = useId();
 	const { children, className, path, ...otherProps } = useContextSystem(
 		props,

packages/components/src/navigator/test/index.tsx

@@ -642,6 +642,14 @@ describe( 'Navigator', () => {
 		).toHaveAttribute( 'id', INVALID_HTML_ATTRIBUTE.escaped );
 	} );
 
+	it( 'should warn if the `path` prop does not follow the required format', () => {
+		render( <NavigatorScreen path="not-valid">Test</NavigatorScreen> );
+
+		expect( console ).toHaveWarnedWith(
+			'wp.components.NavigatorScreen: the `path` should follow a URL-like scheme; it should start with and be separated by the `/` character.'
+		);
+	} );
+
 	it( 'should match correctly paths with named arguments', async () => {
 		const user = userEvent.setup();