Permit plugins to add assets directly to the bundle in Rollup 1.x

src/rollup/index.ts

@@ -272,6 +272,16 @@ export default async function rollup(rawInputOptions: GenericConfigObject): Prom
 			throw error;
 		}
 		await graph.pluginDriver.hookSeq('generateBundle', [outputOptions, outputBundle, isWrite]);
+		for (const key of Object.keys(outputBundle)) {
+			const file = outputBundle[key] as any;
+			if (!file.type) {
+				graph.warnDeprecation(
+					'A plugin is directly adding properties to the bundle object in the "generateBundle" hook. This is deprecated and will be removed in a future Rollup version, please use "this.emitAsset" instead.',
+					false
+				);
+				file.type = 'asset';
+			}
+		}
 		graph.pluginDriver.finaliseAssets();
 
 		timeEnd('GENERATE', 1);

test/form/samples/deprecated/emit-asset-hacky/_config.js

@@ -0,0 +1,16 @@
+module.exports = {
+	description: 'supports emitting assets in a hacky way by editing the bundle object',
+	options: {
+		strictDeprecations: false,
+		plugins: {
+			generateBundle(options, outputBundle) {
+				const file = {
+					fileName: 'my-hacky-asset.txt',
+					isAsset: true,
+					source: 'My Hacky Source'
+				};
+				outputBundle[file.fileName] = file;
+			}
+		}
+	}
+};

test/form/samples/deprecated/emit-asset-hacky/_expected/amd.js

@@ -0,0 +1,5 @@
+define(function () { 'use strict';
+
+	console.log('main');
+
+});

test/form/samples/deprecated/emit-asset-hacky/_expected/cjs.js

@@ -0,0 +1,3 @@
+'use strict';
+
+console.log('main');

test/form/samples/deprecated/emit-asset-hacky/_expected/es.js

@@ -0,0 +1 @@
+console.log('main');

test/form/samples/deprecated/emit-asset-hacky/_expected/iife.js

@@ -0,0 +1,6 @@
+(function () {
+	'use strict';
+
+	console.log('main');
+
+}());

test/form/samples/deprecated/emit-asset-hacky/_expected/my-hacky-asset.txt

@@ -0,0 +1 @@
+My Hacky Source

test/form/samples/deprecated/emit-asset-hacky/_expected/system.js

@@ -0,0 +1,10 @@
+System.register([], function () {
+	'use strict';
+	return {
+		execute: function () {
+
+			console.log('main');
+
+		}
+	};
+});

test/form/samples/deprecated/emit-asset-hacky/_expected/umd.js

@@ -0,0 +1,8 @@
+(function (factory) {
+	typeof define === 'function' && define.amd ? define(factory) :
+	factory();
+}(function () { 'use strict';
+
+	console.log('main');
+
+}));

test/form/samples/deprecated/emit-asset-hacky/main.js

@@ -0,0 +1 @@
+console.log('main');