set up tests for omitted scoping attributes

test/css/index.js

@@ -1,6 +1,6 @@
 import assert from "assert";
 import * as fs from "fs";
-import { svelte } from "../helpers.js";
+import { env, svelte } from "../helpers.js";
 
 function tryRequire(file) {
 	try {
@@ -23,19 +23,45 @@ describe("css", () => {
 		}
 
 		(solo ? it.only : it)(dir, () => {
-			const config = tryRequire(`./samples/${dir}/_config.js`) || {};
+			const config = Object.assign(tryRequire(`./samples/${dir}/_config.js`) || {}, {
+				format: 'iife',
+				name: 'SvelteComponent'	
+			});
 			const input = fs
 				.readFileSync(`test/css/samples/${dir}/input.html`, "utf-8")
 				.replace(/\s+$/, "");
 
-			const actual = svelte.compile(input, config).css;
-			fs.writeFileSync(`test/css/samples/${dir}/_actual.css`, actual);
-			const expected = fs.readFileSync(
-				`test/css/samples/${dir}/expected.css`,
-				"utf-8"
-			);
+			const actual = svelte.compile(input, config);
+			fs.writeFileSync(`test/css/samples/${dir}/_actual.css`, actual.css);
+			const expected = {
+				html: read(`test/css/samples/${dir}/expected.html`),
+				css: read(`test/css/samples/${dir}/expected.css`)
+			};
+
+			assert.equal(actual.css.trim(), expected.css.trim());
+
+			// verify that the right elements have scoping selectors
+			if (expected.html !== null) {
+				return env().then(window => {
+					const Component = eval(`(function () { ${actual.code}; return SvelteComponent; }())`);
+					const target = window.document.querySelector("main");
+
+					new Component({ target });
+					const html = target.innerHTML;
 
-			assert.equal(actual.trim(), expected.trim());
+					fs.writeFileSync(`test/css/samples/${dir}/_actual.html`, html);
+
+					assert.equal(html.trim(), expected.html.trim());
+				});
+			}
 		});
 	});
 });
+
+function read(file) {
+	try {
+		return fs.readFileSync(file, 'utf-8');
+	} catch(err) {
+		return null;
+	}
+}