From 34d2fbfa58e447a3bcc695a1f5a77841e072152f Mon Sep 17 00:00:00 2001
From: Rich Harris <richard.a.harris@gmail.com>
Date: Sun, 15 Apr 2018 18:04:27 -0400
Subject: [PATCH] remove ES5 constraint

---
 src/shared/.eslintrc.json                     |  2 +-
 src/shared/_build.js                          |  7 +---
 test/runtime/index.js                         | 32 -------------------
 .../samples/binding-indirect/_config.js       |  1 -
 .../samples/function-in-expression/_config.js |  2 --
 test/store/index.js                           | 17 ----------
 6 files changed, 2 insertions(+), 59 deletions(-)

diff --git a/src/shared/.eslintrc.json b/src/shared/.eslintrc.json
index 46f1957077..cd108372ce 100644
--- a/src/shared/.eslintrc.json
+++ b/src/shared/.eslintrc.json
@@ -29,7 +29,7 @@
         "plugin:import/warnings"
     ],
     "parserOptions": {
-        "ecmaVersion": 6,
+        "ecmaVersion": 9,
         "sourceType": "module"
     },
     "settings": {
diff --git a/src/shared/_build.js b/src/shared/_build.js
index 3cc523e7cd..72bd5ab2a8 100644
--- a/src/shared/_build.js
+++ b/src/shared/_build.js
@@ -9,18 +9,13 @@ fs.readdirSync(__dirname).forEach(file => {
 
 	const source = fs.readFileSync(path.join(__dirname, file), 'utf-8');
 	const ast = acorn.parse(source, {
-		ecmaVersion: 6,
+		ecmaVersion: 9,
 		sourceType: 'module'
 	});
 
 	ast.body.forEach(node => {
 		if (node.type !== 'ExportNamedDeclaration') return;
 
-		// check no ES6+ slipped in
-		acorn.parse(source.slice(node.declaration.start, node.end), {
-			ecmaVersion: 5
-		});
-
 		const declaration = node.declaration;
 		if (!declaration) return;
 
diff --git a/test/runtime/index.js b/test/runtime/index.js
index a184bb46d0..b491dafa20 100644
--- a/test/runtime/index.js
+++ b/test/runtime/index.js
@@ -74,38 +74,6 @@ describe("runtime", () => {
 			compileOptions.immutable = config.immutable;
 			compileOptions.parser = v2 ? 'v2' : 'v1';
 
-			// check that no ES2015+ syntax slipped in
-			if (!config.allowES2015) {
-				try {
-					const source = fs.readFileSync(
-						`test/runtime/samples/${dir}/main${v2 ? '-v2' : ''}.html`,
-						"utf-8"
-					);
-					const { code } = compile(source, compileOptions);
-					const startIndex = code.indexOf("function create_main_fragment"); // may change!
-					if (startIndex === -1) throw new Error("missing create_main_fragment");
-					const endIndex = code.lastIndexOf("export default");
-					const es5 =
-						code.slice(0, startIndex).split('\n').map(x => spaces(x.length)).join('\n') +
-						code.slice(startIndex, endIndex);
-
-					acorn.parse(es5, { ecmaVersion: 5 });
-
-					if (/Object\.assign/.test(es5)) {
-						throw new Error(
-							"cannot use Object.assign in generated code, as it is not supported everywhere"
-						);
-					}
-				} catch (err) {
-					failed.add(dir);
-					if (err.frame) {
-						console.error(chalk.red(err.frame)); // eslint-disable-line no-console
-					}
-					showOutput(cwd, { shared, format: 'cjs', store: !!compileOptions.store, v2 }, compile); // eslint-disable-line no-console
-					throw err;
-				}
-			}
-
 			Object.keys(require.cache)
 				.filter(x => x.endsWith(".html"))
 				.forEach(file => {
diff --git a/test/runtime/samples/binding-indirect/_config.js b/test/runtime/samples/binding-indirect/_config.js
index 9fdfa23a25..343cd0d0d3 100644
--- a/test/runtime/samples/binding-indirect/_config.js
+++ b/test/runtime/samples/binding-indirect/_config.js
@@ -7,7 +7,6 @@ const tasks = [
 
 export default {
 	'skip-ssr': true,
-	allowES2015: true,
 
 	data: {
 		tasks,
diff --git a/test/runtime/samples/function-in-expression/_config.js b/test/runtime/samples/function-in-expression/_config.js
index 14cfb8f89f..9b79770eb9 100644
--- a/test/runtime/samples/function-in-expression/_config.js
+++ b/test/runtime/samples/function-in-expression/_config.js
@@ -1,6 +1,4 @@
 export default {
-	allowES2015: true,
-
 	data: {
 		numbers: [ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 ]
 	},
diff --git a/test/store/index.js b/test/store/index.js
index fd84322d35..0e989c03f5 100644
--- a/test/store/index.js
+++ b/test/store/index.js
@@ -5,23 +5,6 @@ import { parse } from 'acorn';
 import { Store } from '../../store.js';
 
 describe('store', () => {
-	it('is written in ES5', () => {
-		const source = fs.readFileSync('store.js', 'utf-8');
-
-		const ast = parse(source, {
-			sourceType: 'module'
-		});
-
-		const magicString = new MagicString(source);
-		ast.body.forEach(node => {
-			if (/^(Im|Ex)port/.test(node.type)) magicString.remove(node.start, node.end);
-		});
-
-		parse(magicString.toString(), {
-			ecmaVersion: 5
-		});
-	});
-
 	describe('get', () => {
 		it('gets a specific key', () => {
 			const store = new Store({