fix(prompts): handle trailing backslash in path prompt directory mode

.changeset/path-windows-separator.md

@@ -0,0 +1,5 @@
+---
+"@clack/prompts": patch
+---
+
+Fix the `path` prompt in `directory` mode on Windows: typing a trailing `\` after a directory now lists its children instead of showing no matches.

packages/prompts/src/path.ts

@@ -1,5 +1,5 @@
 import { existsSync, lstatSync, readdirSync } from 'node:fs';
-import { dirname, join } from 'node:path';
+import { dirname, join, sep } from 'node:path';
 import type { Validate } from '@clack/core';
 import { runValidation } from '@clack/core';
 import { autocomplete } from './autocomplete.js';
@@ -87,21 +87,23 @@ export const path = (opts: PathOptions) => {
 
 			try {
 				let searchPath: string;
+				// `sep` is `\` on Windows, where both separators are valid
+				const hasTrailingSeparator = userInput.endsWith('/') || userInput.endsWith(sep);
 
 				if (!existsSync(userInput)) {
 					searchPath = dirname(userInput);
 				} else {
 					const stat = lstatSync(userInput);
-					if (stat.isDirectory() && (!opts.directory || userInput.endsWith('/'))) {
+					if (stat.isDirectory() && (!opts.directory || hasTrailingSeparator)) {
 						searchPath = userInput;
 					} else {
 						searchPath = dirname(userInput);
 					}
 				}
 
-				// Strip trailing slash so startsWith matches the directory itself among its siblings
+				// Strip the trailing separator so startsWith matches the directory itself among its siblings
 				const prefix =
-					userInput.length > 1 && userInput.endsWith('/') ? userInput.slice(0, -1) : userInput;
+					userInput.length > 1 && hasTrailingSeparator ? userInput.slice(0, -1) : userInput;
 
 				const items = readdirSync(searchPath)
 					.map((item) => {

packages/prompts/test/path-win32.test.ts

@@ -0,0 +1,72 @@
+import { vol } from 'memfs';
+import { beforeEach, describe, expect, test, vi } from 'vitest';
+import * as prompts from '../src/index.js';
+import { MockReadable, MockWritable } from './test-utils.js';
+
+// Run the path prompt with Windows path semantics on any OS. memfs only knows
+// POSIX paths here, so `C:\tmp\foo` is looked up as `/tmp/foo`.
+vi.mock('node:path', async (importOriginal) => {
+	const { win32 } = await importOriginal<typeof import('node:path')>();
+	return { ...win32, default: win32 };
+});
+
+vi.mock('node:fs', async () => {
+	const { fs } = await import('memfs');
+	const toPosix = (path: string) => path.replace(/^[a-zA-Z]:/, '').replaceAll('\\', '/');
+	return {
+		existsSync: (path: string) => fs.existsSync(toPosix(path)),
+		lstatSync: (path: string) => fs.lstatSync(toPosix(path)),
+		readdirSync: (path: string) => fs.readdirSync(toPosix(path)),
+	};
+});
+
+describe('path (win32)', () => {
+	let output: MockWritable;
+	let input: MockReadable;
+
+	beforeEach(() => {
+		output = new MockWritable();
+		input = new MockReadable();
+		vol.reset();
+		vol.fromJSON(
+			{
+				'./foo/bar.txt': '1',
+				'./hello/world.jpg': '2',
+				'./root.zip': '3',
+			},
+			'/tmp'
+		);
+	});
+
+	test('directory mode traverses into child when trailing backslash entered', async () => {
+		const result = prompts.path({
+			message: 'foo',
+			initialValue: 'C:\\tmp',
+			directory: true,
+			input,
+			output,
+		});
+
+		input.emit('keypress', '\\', { name: '\\' });
+		input.emit('keypress', '', { name: 'return' });
+		// cancel instead of hanging if return did not submit
+		input.emit('keypress', '', { name: 'escape' });
+
+		expect(await result).toBe('C:\\tmp\\foo');
+	});
+
+	test('directory mode lists children of an initial value ending in a backslash', async () => {
+		const result = prompts.path({
+			message: 'foo',
+			initialValue: 'C:\\tmp\\',
+			directory: true,
+			input,
+			output,
+		});
+
+		input.emit('keypress', '', { name: 'return' });
+		input.emit('keypress', '', { name: 'escape' });
+
+		expect(await result).toBe('C:\\tmp\\foo');
+	});
+});