Update systemJS exports in destructuring assignments via injecting an…

… IIFE

src/ast/nodes/AssignmentExpression.ts

@@ -1,7 +1,9 @@
 import MagicString from 'magic-string';
 import { RenderOptions } from '../../utils/renderHelpers';
+import { getSystemExportStatement } from '../../utils/systemJsRendering';
 import { ExecutionPathOptions } from '../ExecutionPathOptions';
 import { EMPTY_PATH, ObjectPath, UNKNOWN_PATH } from '../values';
+import Variable from '../variables/Variable';
 import * as NodeType from './NodeType';
 import { ExpressionNode, NodeBase } from './shared/Node';
 import { PatternNode } from './shared/Pattern';
@@ -47,12 +49,24 @@ export default class AssignmentExpression extends NodeBase {
 	render(code: MagicString, options: RenderOptions) {
 		this.left.render(code, options);
 		this.right.render(code, options);
-		if (options.format === 'system' && this.left.variable && this.left.variable.exportName) {
-			code.prependLeft(
-				code.original.indexOf('=', this.left.end) + 1,
-				` exports('${this.left.variable.exportName}',`
-			);
-			code.appendLeft(this.right.end, `)`);
+		if (options.format === 'system') {
+			if (this.left.variable && this.left.variable.exportName) {
+				code.prependLeft(
+					code.original.indexOf('=', this.left.end) + 1,
+					` exports('${this.left.variable.exportName}',`
+				);
+				code.appendLeft(this.right.end, `)`);
+			} else if ('addExportedVariables' in this.left) {
+				const systemPatternExports: Variable[] = [];
+				this.left.addExportedVariables(systemPatternExports);
+				if (systemPatternExports.length > 0) {
+					code.prependRight(
+						this.start,
+						`function (v) {${getSystemExportStatement(systemPatternExports)} return v;} (`
+					);
+					code.appendLeft(this.end, ')');
+				}
+			}
 		}
 	}
 }

src/ast/nodes/VariableDeclaration.ts

@@ -5,6 +5,7 @@ import {
 	NodeRenderOptions,
 	RenderOptions
 } from '../../utils/renderHelpers';
+import { getSystemExportStatement } from '../../utils/systemJsRendering';
 import { ExecutionPathOptions } from '../ExecutionPathOptions';
 import { EMPTY_PATH, ObjectPath } from '../values';
 import Variable from '../variables/Variable';
@@ -38,27 +39,6 @@ function areAllDeclarationsIncludedAndNotExported(declarations: VariableDeclarat
 	return true;
 }
 
-function renderSystemExports(
-	code: MagicString,
-	systemPatternExports: Variable[],
-	appendPosition: number
-) {
-	if (systemPatternExports.length === 1) {
-		code.appendRight(
-			appendPosition,
-			` exports('${systemPatternExports[0].safeExportName ||
-				systemPatternExports[0].exportName}', ${systemPatternExports[0].getName()});`
-		);
-	} else {
-		code.appendRight(
-			appendPosition,
-			` exports({${systemPatternExports
-				.map(variable => `${variable.safeExportName || variable.exportName}: ${variable.getName()}`)
-				.join(', ')}});`
-		);
-	}
-}
-
 export default class VariableDeclaration extends NodeBase {
 	type: NodeType.tVariableDeclaration;
 	declarations: VariableDeclarator[];
@@ -238,7 +218,7 @@ export default class VariableDeclaration extends NodeBase {
 			code.appendLeft(renderedContentEnd, separatorString);
 		}
 		if (systemPatternExports.length > 0) {
-			renderSystemExports(code, systemPatternExports, renderedContentEnd);
+			code.appendLeft(renderedContentEnd, ' ' + getSystemExportStatement(systemPatternExports));
 		}
 	}
 }

src/rollup/types.d.ts

@@ -237,7 +237,6 @@ export interface InputOptions {
 	moduleContext?: string | ((id: string) => string) | { [id: string]: string };
 	watch?: WatcherOptions;
 	experimentalCodeSplitting?: boolean;
-	experimentalDynamicImport?: boolean;
 	experimentalTopLevelAwait?: boolean;
 	inlineDynamicImports?: boolean;
 	preserveSymlinks?: boolean;

src/utils/systemJsRendering.ts

@@ -0,0 +1,12 @@
+import Variable from '../ast/variables/Variable';
+
+export function getSystemExportStatement(exportedVariables: Variable[]): string {
+	if (exportedVariables.length === 1) {
+		return `exports('${exportedVariables[0].safeExportName ||
+			exportedVariables[0].exportName}', ${exportedVariables[0].getName()});`;
+	} else {
+		return `exports({${exportedVariables
+			.map(variable => `${variable.safeExportName || variable.exportName}: ${variable.getName()}`)
+			.join(', ')}});`;
+	}
+}

test/form/samples/system-export-destructuring-assignment/_config.js

@@ -1,5 +1,5 @@
 module.exports = {
-	description: 'Supports destructuring declarations and assignments for SystemJS',
+	description: 'supports destructuring assignments of exports for systemJS',
 	options: {
 		output: {
 			format: 'system'

test/form/samples/system-export-destructuring-assignment/_expected.js

@@ -3,12 +3,16 @@ System.register([], function (exports, module) {
 	return {
 		execute: function () {
 
-			const {a = 1, ...b} = global1, c = exports('c', global2), {d} = global3; exports({a: a, b: b, d: d});
-			const [e, ...f] = global4; exports({e: e, f: f});
-			const {g, x: h = 2, y: {z: i}, a: [j ,k,, l]} = global5; exports({g: g, h: h, i: i, j: j, k: k, l: l});
+			exports({
+				a: void 0,
+				b: void 0,
+				c: void 0
+			});
 
-			var m = exports('m', 1);
-			var {m} = global6; exports('m', m);
+			let a, b, c;
+
+			console.log(function (v) {exports('a', a); return v;} ({a} = someObject));
+			(function (v) {exports({b: b, c: c}); return v;} ({b, c} = someObject));
 
 		}
 	};

test/form/samples/system-export-destructuring-assignment/main.js

@@ -1,6 +1,4 @@
-export const {a = 1, ...b} = global1, c = global2, {d} = global3;
-export const [e, ...f] = global4;
-export const {g, x: h = 2, y: {z: i}, a: [j ,k,, l]} = global5;
+export let a, b, c;
 
-export var m = 1;
-var {m} = global6;
+console.log({a} = someObject);
+({b, c} = someObject);

test/form/samples/system-export-destructuring-declaration/_config.js

@@ -0,0 +1,8 @@
+module.exports = {
+	description: 'supports destructuring declarations for systemJS',
+	options: {
+		output: {
+			format: 'system'
+		}
+	}
+};

test/form/samples/system-export-destructuring-declaration/_expected.js

@@ -0,0 +1,15 @@
+System.register([], function (exports, module) {
+	'use strict';
+	return {
+		execute: function () {
+
+			const {a = 1, ...b} = global1, c = exports('c', global2), {d} = global3; exports({a: a, b: b, d: d});
+			const [e, ...f] = global4; exports({e: e, f: f});
+			const {g, x: h = 2, y: {z: i}, a: [j ,k,, l]} = global5; exports({g: g, h: h, i: i, j: j, k: k, l: l});
+
+			var m = exports('m', 1);
+			var {m} = global6; exports('m', m);
+
+		}
+	};
+});

test/form/samples/system-export-destructuring-declaration/main.js

@@ -0,0 +1,6 @@
+export const {a = 1, ...b} = global1, c = global2, {d} = global3;
+export const [e, ...f] = global4;
+export const {g, x: h = 2, y: {z: i}, a: [j ,k,, l]} = global5;
+
+export var m = 1;
+var {m} = global6;