prevent Vite from copying static assets if directory is called public (…

…#4214)

* prevent Vite from copying static assets if directory is called public - fixes #587

* add test

.changeset/brave-toys-joke.md

@@ -0,0 +1,5 @@
+---
+'@sveltejs/kit': patch
+---
+
+Prevent Vite from copying static assets if directory is called "public"

packages/kit/src/core/build/build_client.js

@@ -89,7 +89,10 @@ export async function build_client({
 					hydratable: !!config.kit.browser.hydrate
 				}
 			})
-		]
+		],
+		// prevent Vite copying the contents of `config.kit.files.assets`,
+		// if it happens to be 'public' instead of 'static'
+		publicDir: false
 	});
 
 	print_config_conflicts(conflicts, 'kit.vite.', 'build_client');

packages/kit/test/prerendering/options/public/robots.txt

@@ -0,0 +1,3 @@
+# https://www.robotstxt.org/robotstxt.html
+User-agent: *
+Disallow:

packages/kit/test/prerendering/options/svelte.config.js

@@ -12,6 +12,10 @@ const config = {
 			}
 		},
 
+		files: {
+			assets: 'public'
+		},
+
 		paths: {
 			base: '/path-base',
 			assets: 'https://cdn.example.com/stuff'

packages/kit/test/prerendering/options/test/test.js

@@ -27,4 +27,8 @@ test('adds CSP headers via meta tag', () => {
 	);
 });
 
+test('does not copy `public` into `_app`', () => {
+	assert.ok(!fs.existsSync(`${build}/_app/robots.txt`));
+});
+
 test.run();