fix(exports): fixes a bug where exports = require(...)() would lead t…

…o SyntaxErrors

src/transformer/before/visitor/visit/visit-binary-expression.ts

@@ -8,13 +8,14 @@ import {nodeContainsSuper} from "../../../util/node-contains-super";
 import {addExportModifier} from "../../../util/add-export-modifier";
 import {isRequireCall} from "../../../util/is-require-call";
 import {getModuleExportsFromRequireDataInContext} from "../../../util/get-module-exports-from-require-data-in-context";
+import {isExpression} from "../../../util/is-expression";
 
 /**
  * Visits the given BinaryExpression
  * @param {BeforeVisitorOptions<BinaryExpression>} options
  * @returns {VisitResult<BinaryExpression>}
  */
-export function visitBinaryExpression ({node, sourceFile, context}: BeforeVisitorOptions<BinaryExpression>): VisitResult<Node> {
+export function visitBinaryExpression ({node, sourceFile, context, continuation}: BeforeVisitorOptions<BinaryExpression>): VisitResult<Node> {
 	// Check if the left-hand side contains exports. For example: 'exports = ...' or 'exports.foo = 1' or event 'module.exports = 1'
 	const exportsData = getExportsData(node.left);
 	const right = walkThroughFillerNodes(node.right);
@@ -158,14 +159,22 @@ export function visitBinaryExpression ({node, sourceFile, context}: BeforeVisito
 
 			// Convert it into an ExportAssignment instead if possible
 			else {
+
 				// Check if the rightvalue represents a require(...) call.
 				const requireData = isRequireCall(node.right, sourceFile, context);
 
 				// If it doesn't, export the right side
 				if (!requireData.match) {
 					if (!context.isDefaultExported) {
 						context.markDefaultAsExported();
-						context.addTrailingStatements(createExportAssignment(undefined, undefined, false, node.right));
+						const continuationResult = continuation(node.right);
+						if (continuationResult == null || Array.isArray(continuationResult) || !isExpression(continuationResult)) {
+							return undefined;
+						}
+
+						else {
+							context.addTrailingStatements(createExportAssignment(undefined, undefined, false, continuationResult));
+						}
 					}
 					return undefined;
 				}

test/exports.test.ts

@@ -483,6 +483,33 @@ test("Converts 'exports = require(...)' syntax into namespace re-exports if the
 	);
 });
 
+test("Converts 'exports = require(...)()' syntax into namespace import along with a default export if the required module has named exports. #1", t => {
+	const bundle = generateTransformerResult([
+		{
+			entry: true,
+			fileName: "index.ts",
+			text: `
+				module.exports = require("./foo")();
+			`
+		},
+		{
+			entry: true,
+			fileName: "foo.ts",
+			text: `
+				exports.readFileSync = () => {};
+			`
+		}
+	]);
+	const [file] = bundle;
+	t.deepEqual(
+		formatCode(file.text),
+		formatCode(`\
+		import * as foo from "./foo";
+		export default foo();
+		`)
+	);
+});
+
 test("Converts 'exports = require(...)' syntax into a default export if the required module has one. #1", t => {
 	const bundle = generateTransformerResult([
 		{
@@ -526,4 +553,24 @@ test("Converts 'exports = require(...)' syntax into a default export if the requ
 		export {default} from "./foo";
 		`)
 	);
+});
+
+test("Converts 'exports = require(...)()' syntax into a default export if the required module is unknown. #2", t => {
+	const bundle = generateTransformerResult([
+		{
+			entry: true,
+			fileName: "index.ts",
+			text: `
+				module.exports = require("./foo")();
+			`
+		}
+	]);
+	const [file] = bundle;
+	t.deepEqual(
+		formatCode(file.text),
+		formatCode(`\
+		import foo from "./foo";
+		export default foo();
+		`)
+	);
 });