Use the async transform API, add caller and drop dependencies on the …

…beta/rc range. (#162)

* Use the async transform API and drop dependencies on the beta/rc range.

* Update the README for gulp-babel@8.x

.travis.yml

@@ -2,5 +2,5 @@ sudo: false
 language: node_js
 node_js:
   - 'stable'
+  - '8'
   - '6'
-  - '4'

README.md

@@ -1,3 +1,6 @@
+> This readme is for gulp-babel v8 + Babel v7
+> Check the [7.x branch](https://github.com/babel/gulp-babel/tree/v7-maintenance) for docs with Babel v6 usage
+
 # gulp-babel [![npm](https://img.shields.io/npm/v/gulp-babel.svg?maxAge=2592000)](https://www.npmjs.com/package/gulp-babel) [![Build Status](https://travis-ci.org/babel/gulp-babel.svg?branch=master)](https://travis-ci.org/babel/gulp-babel)
 
 > Use next generation JavaScript, today, with [Babel](https://babeljs.io)
@@ -7,14 +10,14 @@
 
 ## Install
 
-Install `gulp-babel@next` if you want to get the pre-release of the next version of `gulp-babel`.
+Install `gulp-babel` if you want to get the pre-release of the next version of `gulp-babel`.
 
 ```
-# Babel 7 (use exact dependencies while in beta, not `^`)
-$ npm install --save-dev gulp-babel@next @babel/core @babel/preset-env
+# Babel 7
+$ npm install --save-dev gulp-babel @babel/core @babel/preset-env
 
 # Babel 6
-$ npm install --save-dev gulp-babel babel-core babel-preset-env
+$ npm install --save-dev gulp-babel@7 babel-core babel-preset-env
 ```
 
 ## Usage
@@ -105,7 +108,8 @@ If you're attempting to use features such as generators, you'll need to add `tra
 Install the runtime:
 
 ```
-$ npm install --save-dev @babel/plugin-transform-runtime
+$ npm install --save-dev @babel/plugin-transform-runtime 
+$ npm install --save @babel/runtime 
 ```
 
 Use it as plugin:

index.js

@@ -24,38 +24,67 @@ module.exports = function (opts) {
 			return;
 		}
 
-		try {
-			const fileOpts = Object.assign({}, opts, {
-				filename: file.path,
-				filenameRelative: file.relative,
-				sourceMap: Boolean(file.sourceMap),
-				sourceFileName: file.relative
-			});
+		if (!supportsCallerOption()) {
+			cb(new PluginError('gulp-babel', '@babel/core@^7.0.0 is required'));
+			return;
+		}
 
-			const res = babel.transform(file.contents.toString(), fileOpts);
+		const fileOpts = Object.assign({}, opts, {
+			filename: file.path,
+			filenameRelative: file.relative,
+			sourceMap: Boolean(file.sourceMap),
+			sourceFileName: file.relative,
+			caller: Object.assign(
+				{name: 'babel-gulp'},
+				opts.caller
+			)
+		});
 
-			if (res !== null) {
+		babel.transformAsync(file.contents.toString(), fileOpts).then(res => {
+			if (res) {
 				if (file.sourceMap && res.map) {
 					res.map.file = replaceExtension(file.relative);
 					applySourceMap(file, res.map);
 				}
 
-				if (!res.ignored) {
-					file.contents = new Buffer(res.code); // eslint-disable-line unicorn/no-new-buffer
-					file.path = replaceExtension(file.path);
-				}
+				file.contents = new Buffer(res.code); // eslint-disable-line unicorn/no-new-buffer
+				file.path = replaceExtension(file.path);
 
 				file.babel = res.metadata;
 			}
 
 			this.push(file);
-		} catch (err) {
+		}).catch(err => {
 			this.emit('error', new PluginError('gulp-babel', err, {
 				fileName: file.path,
 				showProperties: false
 			}));
-		}
-
-		cb();
+		}).then(
+			() => cb(),
+			() => cb()
+		);
 	});
 };
+
+// Note: We can remove this eventually, I'm just adding it so that people have
+// a little time to migrate to the newer RCs of @babel/core without getting
+// hard-to-diagnose errors about unknown 'caller' options.
+let supportsCallerOptionFlag;
+function supportsCallerOption() {
+	if (supportsCallerOptionFlag === undefined) {
+		try {
+			// Rather than try to match the Babel version, we just see if it throws
+			// when passed a 'caller' flag, and use that to decide if it is supported.
+			babel.loadPartialConfig({
+				caller: undefined,
+				babelrc: false,
+				configFile: false
+			});
+			supportsCallerOptionFlag = true;
+		} catch (err) {
+			supportsCallerOptionFlag = false;
+		}
+	}
+
+	return supportsCallerOptionFlag;
+}

package.json

@@ -9,7 +9,7 @@
     "Charles Samborski <demurgos@demurgos.net> (demurgos.net)"
   ],
   "engines": {
-    "node": ">=4"
+    "node": ">=6"
   },
   "scripts": {
     "test": "xo && mocha"
@@ -44,13 +44,13 @@
     "vinyl-sourcemaps-apply": "^0.2.0"
   },
   "peerDependencies": {
-    "@babel/core": "7 || ^7.0.0-0"
+    "@babel/core": "^7.0.0"
   },
   "devDependencies": {
-    "@babel/core": "7.0.0-beta.41",
-    "@babel/plugin-transform-arrow-functions": "7.0.0-beta.41",
-    "@babel/plugin-transform-block-scoping": "7.0.0-beta.41",
-    "@babel/plugin-transform-classes": "7.0.0-beta.41",
+    "@babel/core": "^7.0.0",
+    "@babel/plugin-transform-arrow-functions": "^7.0.0",
+    "@babel/plugin-transform-block-scoping": "^7.0.0",
+    "@babel/plugin-transform-classes": "^7.0.0",
     "gulp-sourcemaps": "^1.1.1",
     "mocha": "^5.0.0",
     "pre-commit": "^1.2.2",