Update stage-4 preset to target latest Node.js 10 & 12 and latest sta…

…ge-4 updates

README.md

@@ -274,7 +274,7 @@ Install `babel-plugin-webpack-alias-7` as a dev-dependency. Then add the plugin
 
 Aspires to bring [finished ECMAScript proposals](https://github.com/tc39/proposals/blob/master/finished-proposals.md) to AVA's test and helper files.
 
-Efficiently applies the minimum of transforms to run the latest JavaScript syntax on Node.js 8, 10 and 12.
+Efficiently applies the minimum of transforms to run the latest JavaScript syntax on Node.js 10 and 12.
 
 Built-ins are not added or extended, so features like Proxies, `Array.prototype.includes` or `String.prototype.padStart` will only be available if the Node.js version running the tests supports it. Consult [node.green] for details.
 
@@ -310,13 +310,16 @@ Not all proposals can be supported via Babel transforms, see below for details.
 | [`String.prototype.matchAll`][string-matchall]                           | No
 | [`import()`][dynamic-import]                                             | Yes
 | [`Promise.allSettled`][promise-allsettled]                               | No
+| [Optional Chaining][chaining]                                            | Yes
+| [Nullish coalescing Operator][nullish-coalescing]                        | Yes
 
 † [`@babel/plugin-proposal-async-generator-functions`](https://www.npmjs.com/package/@babel/plugin-proposal-async-generator-functions) relies on `Symbol.asyncIterator`, which AVA does not polyfill for you.
 
 [array-includes]: https://github.com/tc39/Array.prototype.includes
 [async-iteration]: https://github.com/tc39/proposal-async-iteration
 [atomics]: https://github.com/tc39/ecmascript_sharedmem
 [Babel options]: https://babeljs.io/docs/en/options
+[chaining]: https://github.com/tc39/proposal-optional-chaining
 [dot-all]: https://github.com/tc39/proposal-regexp-dotall-flag
 [dynamic-import]: https://github.com/tc39/proposal-dynamic-import
 [finally]: https://github.com/tc39/proposal-promise-finally
@@ -327,6 +330,7 @@ Not all proposals can be supported via Babel transforms, see below for details.
 [lookbehind]: https://github.com/tc39/proposal-regexp-lookbehind
 [named-groups]: https://github.com/tc39/proposal-regexp-named-groups
 [node.green]: http://node.green
+[nullish-coalescing]: https://github.com/tc39/proposal-nullish-coalescing
 [object-fromentries]: https://github.com/tc39/proposal-object-from-entries
 [object-gopds]: https://github.com/ljharb/proposal-object-getownpropertydescriptors
 [object-values-entries]: https://github.com/tc39/proposal-object-values-entries

package.json

@@ -26,10 +26,9 @@
   "dependencies": {
     "@babel/core": "^7.7.7",
     "@babel/generator": "^7.7.7",
-    "@babel/plugin-proposal-async-generator-functions": "^7.7.4",
     "@babel/plugin-proposal-dynamic-import": "^7.7.4",
-    "@babel/plugin-proposal-optional-catch-binding": "^7.7.4",
-    "@babel/plugin-transform-dotall-regex": "^7.7.7",
+    "@babel/plugin-proposal-nullish-coalescing-operator": "^7.7.4",
+    "@babel/plugin-proposal-optional-chaining": "^7.7.5",
     "@babel/plugin-transform-modules-commonjs": "^7.7.5",
     "babel-plugin-espower": "^3.0.1",
     "concordance": "^4.0.0",

stage-4-plugins/best-match.js

@@ -3,20 +3,16 @@ const process = require('process'); // eslint-disable-line node/prefer-global/pr
 
 function getClosestVersion() {
 	if (!process.versions.v8) {
-		// Assume compatibility with Node.js 8.9.4
-		return 'v8-6.1';
+		// Assume compatibility with Node.js 10.18.0
+		return 'v8-6.8';
 	}
 
 	const v8 = parseFloat(process.versions.v8);
-	if (v8 >= 6.6) {
-		return 'v8-6.6';
+	if (v8 >= 6.8) {
+		return 'v8-6.8';
 	}
 
-	if (v8 >= 6.2) {
-		return 'v8-6.2';
-	}
-
-	return 'v8-6.1';
+	return 'v8-6.8';
 }
 
 module.exports = require(`./${getClosestVersion()}.json`);

test/stage-4.js

@@ -33,10 +33,8 @@ function buildsCorrectPreset(t, node, v8, mapping) {
 buildsCorrectPreset.title = (_, node) => `builds correct preset for Node.js ${node}`;
 
 for (const [node, v8, mapping] of [
-	['not-v8-at-all', null, '../stage-4-plugins/v8-6.1.json'],
-	['8.9.4', '6.1.534.50', '../stage-4-plugins/v8-6.1.json'],
-	['8.16.0', '6.2.414.77', '../stage-4-plugins/v8-6.2.json'],
-	['10.0.0', '6.6.346.24-node.5', '../stage-4-plugins/v8-6.6.json']
+	['not-v8-at-all', null, '../stage-4-plugins/v8-6.8.json'],
+	['10.18.0', '6.8.275.32-node.54', '../stage-4-plugins/v8-6.8.json']
 ]) {
 	test(buildsCorrectPreset, node, v8, mapping);
 }