Do not expose synthetic namespace export in entries and namespaces

src/Module.ts

@@ -351,7 +351,11 @@ export default class Module {
 				if (name !== 'default') allExportNames.add(name);
 			}
 		}
-
+		// We do not count the synthetic namespace as a regular export to hide it
+		// from entry signatures and namespace objects
+		if (typeof this.info.syntheticNamedExports === 'string') {
+			allExportNames.delete(this.info.syntheticNamedExports);
+		}
 		return allExportNames;
 	}
 
@@ -412,7 +416,6 @@ export default class Module {
 		}
 		const exportNamesByVariable = new Map<Variable, string[]>();
 		for (const exportName of this.getAllExportNames()) {
-			if (exportName === this.info.syntheticNamedExports) continue;
 			let [tracedVariable] = this.getVariableForExportName(exportName);
 			if (tracedVariable instanceof ExportDefaultVariable) {
 				tracedVariable = tracedVariable.getOriginalVariable();
@@ -477,7 +480,8 @@ export default class Module {
 			[this.syntheticNamespace] = this.getVariableForExportName(
 				typeof this.info.syntheticNamedExports === 'string'
 					? this.info.syntheticNamedExports
-					: 'default'
+					: 'default',
+				{ onlyExplicit: true }
 			);
 		}
 		if (!this.syntheticNamespace) {
@@ -493,10 +497,12 @@ export default class Module {
 		{
 			importerForSideEffects,
 			isExportAllSearch,
+			onlyExplicit,
 			searchedNamesAndModules
 		}: {
 			importerForSideEffects?: Module;
 			isExportAllSearch?: boolean;
+			onlyExplicit?: boolean;
 			searchedNamesAndModules?: Map<string, Set<Module | ExternalModule>>;
 		} = EMPTY_OBJECT
 	): [variable: Variable | null, indirectExternal?: boolean] {
@@ -521,7 +527,6 @@ export default class Module {
 				false,
 				searchedNamesAndModules
 			);
-
 			if (!variable) {
 				return this.error(
 					errMissingExport(reexportDeclaration.localName, this.id, reexportDeclaration.module.id),
@@ -552,6 +557,10 @@ export default class Module {
 			return [variable];
 		}
 
+		if (onlyExplicit) {
+			return [null];
+		}
+
 		if (name !== 'default') {
 			const foundNamespaceReexport =
 				name in this.namespaceReexportsByName
@@ -1021,6 +1030,10 @@ export default class Module {
 		const foundInternalDeclarations = new Map<Variable, Module>();
 		const foundExternalDeclarations = new Set<ExternalVariable>();
 		for (const module of this.exportAllModules) {
+			// Synthetic namespaces should not hide "regular" exports of the same name
+			if (module.info.syntheticNamedExports === name) {
+				continue;
+			}
 			const [variable, indirectExternal] = getVariableForExportNameRecursive(
 				module,
 				name,

src/utils/error.ts

@@ -407,7 +407,7 @@ export function errSyntheticNamedExportsNeedNamespaceExport(
 			syntheticNamedExportsOption
 		)}' needs ${
 			typeof syntheticNamedExportsOption === 'string' && syntheticNamedExportsOption !== 'default'
-				? `an export named "${syntheticNamedExportsOption}"`
+				? `an explicit export named "${syntheticNamedExportsOption}"`
 				: 'a default export'
 		} that does not reexport an unresolved named export of the same module.`
 	};

test/form/samples/merge-namespaces-non-live/_expected.js

@@ -13,10 +13,12 @@ function _mergeNamespaces(n, m) {
 	return Object.freeze(n);
 }
 
-const __synthetic = { foo: 'foo' };
+const __synthetic$1 = { module: 'synthetic' };
+
+const __synthetic = { module: 'reexport' };
 
 var ns = /*#__PURE__*/Object.freeze(/*#__PURE__*/_mergeNamespaces({
 	__proto__: null
-}, [__synthetic, external1, external2]));
+}, [__synthetic, __synthetic$1, external1, external2]));
 
 console.log(ns);

test/form/samples/merge-namespaces-non-live/reexport.js

@@ -1,3 +1,4 @@
 export * from 'external1';
 export * from './synthetic';
 export * from 'external2';
+export const __synthetic = { module: 'reexport' };

test/form/samples/merge-namespaces-non-live/synthetic.js

@@ -1 +1 @@
-export const __synthetic = { foo: 'foo' };
+export const __synthetic = { module: 'synthetic' };

test/form/samples/merge-namespaces/_expected.js

@@ -16,10 +16,12 @@ function _mergeNamespaces(n, m) {
 	return Object.freeze(n);
 }
 
-const __synthetic = { foo: 'foo' };
+const __synthetic$1 = { module: 'synthetic' };
+
+const __synthetic = { module: 'reexport' };
 
 var ns = /*#__PURE__*/Object.freeze(/*#__PURE__*/_mergeNamespaces({
 	__proto__: null
-}, [__synthetic, external1, external2]));
+}, [__synthetic, __synthetic$1, external1, external2]));
 
 console.log(ns);

test/form/samples/merge-namespaces/reexport.js

@@ -1,3 +1,4 @@
 export * from 'external1';
 export * from './synthetic';
 export * from 'external2';
+export const __synthetic = { module: 'reexport' };

test/form/samples/merge-namespaces/synthetic.js

@@ -1 +1 @@
-export const __synthetic = { foo: 'foo' };
+export const __synthetic = { module: 'synthetic' };

test/function/samples/synthetic-named-export-entry/_config.js

@@ -0,0 +1,39 @@
+const assert = require('assert');
+const path = require('path');
+const ID_MAIN = path.join(__dirname, 'main.js');
+const ID_OVERRIDE = path.join(__dirname, 'override.js');
+const ID_NOOVERRIDE = path.join(__dirname, 'noOverride.js');
+const ID_HIDDENNAMESPACE = path.join(__dirname, 'hiddenNamespace.js');
+
+module.exports = {
+	description: 'does not expose synthetic named exports on entry points',
+	options: {
+		plugins: [
+			{
+				transform(code, id) {
+					switch (id) {
+						case ID_MAIN:
+							return { syntheticNamedExports: 'synthMain' };
+						case ID_OVERRIDE:
+							return { syntheticNamedExports: 'synthOverride' };
+						case ID_NOOVERRIDE:
+							return { syntheticNamedExports: 'synthNoOverride' };
+						case ID_HIDDENNAMESPACE:
+							return { syntheticNamedExports: 'synthHiddenNamespace' };
+					}
+				}
+			}
+		]
+	},
+	exports(exports) {
+		assert.deepStrictEqual(exports, {
+			explicitReexport: { override: true },
+			hiddenNamespace: 'hiddenNamespace',
+			main: 'main',
+			noOverride: 'noOverride',
+			override: 'override',
+			synthHiddenNamespace: 'hidden in override',
+			synthOverride: 'overridden'
+		});
+	}
+};

test/function/samples/synthetic-named-export-entry/hiddenNamespace.js

@@ -0,0 +1,2 @@
+export const hiddenNamespace = 'hiddenNamespace';
+export const synthHiddenNamespace = { hiddenNamespace: true };

test/function/samples/synthetic-named-export-entry/main.js

@@ -0,0 +1,7 @@
+export const main = 'main';
+export const synthMain = { main: true };
+export * from './noOverride.js';
+export * from './override.js';
+export * from './hiddenNamespace.js';
+export const synthOverride = 'overridden';
+export { synthOverride as explicitReexport } from './override.js';

test/function/samples/synthetic-named-export-entry/noOverride.js

@@ -0,0 +1,2 @@
+export const noOverride = 'noOverride';
+export const synthNoOverride = { noOverride: true };

test/function/samples/synthetic-named-export-entry/override.js

@@ -0,0 +1,3 @@
+export const override = 'override';
+export const synthOverride = { override: true };
+export const synthHiddenNamespace = 'hidden in override';

test/function/samples/synthetic-named-exports/circular-synthetic-exports/_config.js

@@ -15,7 +15,7 @@ module.exports = {
 	error: {
 		code: 'SYNTHETIC_NAMED_EXPORTS_NEED_NAMESPACE_EXPORT',
 		id: path.join(__dirname, 'main.js'),
-		message: `Module "main.js" that is marked with 'syntheticNamedExports: "__synthetic"' needs an export named "__synthetic" that does not reexport an unresolved named export of the same module.`,
+		message: `Module "main.js" that is marked with 'syntheticNamedExports: "__synthetic"' needs an explicit export named "__synthetic" that does not reexport an unresolved named export of the same module.`,
 		watchFiles: [path.join(__dirname, 'main.js'), path.join(__dirname, 'dep.js')]
 	}
 };

test/function/samples/synthetic-named-exports/synthetic-exports-need-fallback-export/_config.js

@@ -17,7 +17,7 @@ module.exports = {
 	error: {
 		code: 'SYNTHETIC_NAMED_EXPORTS_NEED_NAMESPACE_EXPORT',
 		id: DEP_ID,
-		message: `Module "dep.js" that is marked with 'syntheticNamedExports: "__synthetic"' needs an export named "__synthetic" that does not reexport an unresolved named export of the same module.`,
+		message: `Module "dep.js" that is marked with 'syntheticNamedExports: "__synthetic"' needs an explicit export named "__synthetic" that does not reexport an unresolved named export of the same module.`,
 		watchFiles: [path.join(__dirname, 'main.js'), DEP_ID]
 	}
 };