fix: better way of preventing unintended exports (#85)

* Revert "Fix exports (#82)"

This reverts commit b9435de.

* fix: better way of preventing unintended exports

sveltejs/svelte#12202 revealed that TypeScript has a harder time tracing imports when they are indirectly exposed, e.g. `function foo(): void; ... export { foo }` instead of `export function foo(): void;`, which can lead to bugs down the line. Ultimately this is a TypeScript limitation but in the meantime adding a lone `export {}` along `export function/const/etc` statements has the same effect as #82

* fix tests

CHANGELOG.md

@@ -1,5 +1,9 @@
 # dts-buddy changelog
 
+## 0.5.1
+
+- Use more TypeScript-friendly way of preventing unintended exports ([#85](https://github.com/Rich-Harris/dts-buddy/pull/85))
+
 ## 0.5.0
 
 - Prevent unintended exports ([#82](https://github.com/Rich-Harris/dts-buddy/pull/82))

src/create-module-declaration.js

@@ -167,9 +167,11 @@ export function create_module_declaration(id, entry, created, resolve) {
 				declaration.alias = get_name(globals.has(name) ? declaration.name : name);
 				mark(declaration);
 
-				export_specifiers.push(
-					declaration.alias === name ? name : `${declaration.alias} as ${name}`
-				);
+				if (declaration.alias !== name) {
+					export_specifiers.push(`${declaration.alias} as ${name}`);
+				} else {
+					declaration.exported = true;
+				}
 			} else {
 				throw new Error('Something strange happened');
 			}
@@ -323,10 +325,15 @@ export function create_module_declaration(id, entry, created, resolve) {
 								}
 							}
 
-							let b = export_modifier.end;
-							const a = b - 6;
-							while (/\s/.test(module.dts[b])) b += 1;
-							result.remove(a, b);
+							if (!exports.has(declaration.alias)) {
+								// remove all export keywords in the initial pass; reinstate as necessary later
+								let b = export_modifier.end;
+								const a = b - 6;
+								while (/\s/.test(module.dts[b])) b += 1;
+								result.remove(a, b);
+							}
+						} else if (declaration.exported) {
+							export_specifiers.push(declaration.alias);
 						}
 					}
 
@@ -391,24 +398,22 @@ export function create_module_declaration(id, entry, created, resolve) {
 			if (mod) content += '\n' + mod;
 		}
 
-		if (export_specifiers.length > 0) {
-			content += `\n\n\texport { ${export_specifiers.join(', ')} };`;
-		}
-
 		// finally, export any bindings that are exported from external modules
 
-		/** @type {string[]} */
-		const specifiers = [];
-
 		for (const name of exports) {
 			const declaration = trace_export(entry, name);
 			if (declaration?.external) {
-				specifiers.push(declaration.alias);
+				export_specifiers.push(declaration.alias);
 			}
 		}
 
-		if (specifiers.length > 0) {
-			content += `\n\texport { ${specifiers.join(', ')} };`;
+		// Always add an export { .. } statement, even if there are no exports. This ensures
+		// that only the public types are exposed to consumers of the declaration file. Due to some
+		// old TypeScript inconsistency, omitting the export statement would expose all types.
+		if (export_specifiers.length > 0) {
+			content += `\n\n\texport { ${export_specifiers.join(', ')} };`;
+		} else {
+			content += '\n\n\texport {};';
 		}
 
 		content += `\n}`;
@@ -500,6 +505,7 @@ export function create_module_declaration(id, entry, created, resolve) {
 				module: '<builtin>',
 				external: false,
 				included: true,
+				exported: false,
 				name,
 				alias: name,
 				dependencies: [],
@@ -527,6 +533,7 @@ function create_external_declaration(binding, alias) {
 		module: binding.id,
 		name: binding.name,
 		alias: '',
+		exported: false,
 		external: true,
 		included: false,
 		dependencies: [],

src/types.d.ts

@@ -11,6 +11,7 @@ interface Declaration {
 	module: string;
 	name: string;
 	alias: string;
+	exported: boolean;
 	external: boolean;
 	included: boolean;
 	dependencies: Reference[];

src/utils.js

@@ -342,6 +342,7 @@ export function get_dts(file, created, resolve) {
 					module: file,
 					name,
 					alias: '',
+					exported: false,
 					included: false,
 					external: false,
 					dependencies: [],

test/samples/ambient-imports/output/index.d.ts

@@ -1,9 +1,9 @@
 /// <reference types="some-ambient-import" />
 
 declare module 'ambient-imports' {
-	interface Foo {}
+	export interface Foo {}
 
-	export { Foo };
+	export {};
 }
 
 //# sourceMappingURL=index.d.ts.map

test/samples/ambient-imports/output/index.d.ts.map

@@ -10,5 +10,5 @@
 	"sourcesContent": [
 		null
 	],
-	"mappings": ";;;WAEiBA,GAAGA"
+	"mappings": ";;;kBAEiBA,GAAGA"
 }

test/samples/basic/output 5.5/index.d.ts

@@ -1,6 +1,6 @@
 declare module 'basic' {
 	/** A vector with two components */
-	interface Vector2 {
+	export interface Vector2 {
 		/** The x component */
 		x: number;
 		/** The y component */
@@ -11,18 +11,18 @@ declare module 'basic' {
 	 * @param a the first vector
 	 * @param b the second vector
 	 * */
-	function add(a: Vector2, b: Vector2): Vector2;
+	export function add(a: Vector2, b: Vector2): Vector2;
 
-	export { Vector2, add };
+	export {};
 }
 
 declare module 'basic/subpackage' {
 	/**
 	 * Multiply two vectors
 	 * */
-	function multiply(a: import("basic").Vector2, b: import("basic").Vector2): import("basic").Vector2;
+	export function multiply(a: import("basic").Vector2, b: import("basic").Vector2): import("basic").Vector2;
 
-	export { multiply };
+	export {};
 }
 
-//# sourceMappingURL=index.d.ts.map
+//# sourceMappingURL=index.d.ts.map

test/samples/basic/output 5.5/index.d.ts.map

@@ -16,5 +16,5 @@
 		null,
 		null
 	],
-	"mappings": ";;WACiBA,OAAOA;;;;;;;;;;;UCKRC,GAAGA;;;;;;;;;UCAHC,QAAQA"
-}
+	"mappings": ";;kBACiBA,OAAOA;;;;;;;;;;;iBCKRC,GAAGA;;;;;;;;;iBCAHC,QAAQA"
+}

test/samples/basic/output/index.d.ts

@@ -1,6 +1,6 @@
 declare module 'basic' {
 	/** A vector with two components */
-	interface Vector2 {
+	export interface Vector2 {
 		/** The x component */
 		x: number;
 		/** The y component */
@@ -11,18 +11,18 @@ declare module 'basic' {
 	 * @param a the first vector
 	 * @param b the second vector
 	 * */
-	function add(a: Vector2, b: Vector2): Vector2;
+	export function add(a: Vector2, b: Vector2): Vector2;
 
-	export { Vector2, add };
+	export {};
 }
 
 declare module 'basic/subpackage' {
 	/**
 	 * Multiply two vectors
 	 * */
-	function multiply(a: import('basic').Vector2, b: import('basic').Vector2): import('basic').Vector2;
+	export function multiply(a: import('basic').Vector2, b: import('basic').Vector2): import('basic').Vector2;
 
-	export { multiply };
+	export {};
 }
 
-//# sourceMappingURL=index.d.ts.map
+//# sourceMappingURL=index.d.ts.map

test/samples/basic/output/index.d.ts.map

@@ -16,5 +16,5 @@
 		null,
 		null
 	],
-	"mappings": ";;WACiBA,OAAOA;;;;;;;;;;;UCKRC,GAAGA;;;;;;;;;UCAHC,QAAQA"
+	"mappings": ";;kBACiBA,OAAOA;;;;;;;;;;;iBCKRC,GAAGA;;;;;;;;;iBCAHC,QAAQA"
 }

test/samples/const-namespace/output 5.0/index.d.ts

@@ -1,9 +1,9 @@
 declare module 'const-namespace' {
-	namespace a {
+	export namespace a {
 		const x: number;
 	}
 
-	export { a };
+	export {};
 }
 
-//# sourceMappingURL=index.d.ts.map
+//# sourceMappingURL=index.d.ts.map

test/samples/const-namespace/output/index.d.ts

@@ -1,9 +1,9 @@
 declare module 'const-namespace' {
-	namespace a {
+	export namespace a {
 		let x: number;
 	}
 
-	export { a };
+	export {};
 }
 
 //# sourceMappingURL=index.d.ts.map

test/samples/declare-module/output/index.d.ts

@@ -1,7 +1,7 @@
 declare module 'declare-module' {
-	interface Foo {}
+	export interface Foo {}
 
-	export { Foo };
+	export {};
 }
 
 //# sourceMappingURL=index.d.ts.map

test/samples/declare-module/output/index.d.ts.map

@@ -10,5 +10,5 @@
 	"sourcesContent": [
 		null
 	],
-	"mappings": ";WAOiBA,GAAGA"
+	"mappings": ";kBAOiBA,GAAGA"
 }

test/samples/deconflict-priority/output/index.d.ts

@@ -1,9 +1,9 @@
 declare module 'deconflict-priority' {
-	function x(foo: Foo, bar: Bar): void;
+	export function x(foo: Foo, bar: Bar): void;
 	interface Foo {}
 	interface Bar {}
 
-	export { x };
+	export {};
 }
 
 //# sourceMappingURL=index.d.ts.map

test/samples/deconflict-priority/output/index.d.ts.map

@@ -16,5 +16,5 @@
 		null,
 		null
 	],
-	"mappings": ";UAIgBA,CAACA;WCJAC,GAAGA;WCCHC,GAAGA"
+	"mappings": ";iBAIgBA,CAACA;WCJAC,GAAGA;WCCHC,GAAGA"
 }

test/samples/enum/output/index.d.ts

@@ -1,11 +1,11 @@
 declare module 'enum' {
-	enum categories {
+	export enum categories {
 		ANIMAL = 0,
 		VEGETABLE = 1,
 		MINERAL = 2
 	}
 
-	export { categories };
+	export {};
 }
 
 //# sourceMappingURL=index.d.ts.map

test/samples/enum/output/index.d.ts.map

@@ -10,5 +10,5 @@
 	"sourcesContent": [
 		null
 	],
-	"mappings": ";MAAYA,UAAUA"
-}
+	"mappings": ";aAAYA,UAAUA"
+}

test/samples/export-default-as/output/index.d.ts

@@ -2,9 +2,9 @@ declare module 'export-default-as' {
 	/**
 	 * Add two numbers
 	 * */
-	function add(a: number, b: number): number;
+	export function add(a: number, b: number): number;
 
-	export { add };
+	export {};
 }
 
 //# sourceMappingURL=index.d.ts.map

test/samples/export-default-as/output/index.d.ts.map

@@ -10,5 +10,5 @@
 	"sourcesContent": [
 		null
 	],
-	"mappings": ";;;;UAMwBA,GAAGA"
+	"mappings": ";;;;iBAMwBA,GAAGA"
 }

test/samples/export-default-function/output/index.d.ts

@@ -1,7 +1,7 @@
 declare module 'export-default-function' {
 	export default function foo(): void;
 
-	export { default };
+	export {};
 }
 
 //# sourceMappingURL=index.d.ts.map

test/samples/export-default-value/output/index.d.ts

@@ -2,7 +2,7 @@ declare module 'export-default-value' {
 	const _default: 42;
 	export default _default;
 
-	export { default };
+	export {};
 }
 
 //# sourceMappingURL=index.d.ts.map

test/samples/export-from/output/index.d.ts

@@ -1,7 +1,7 @@
 declare module 'export-from' {
-	const foo: "hello";
+	export const foo: "hello";
 
-	export { foo };
+	export {};
 }
 
 //# sourceMappingURL=index.d.ts.map

test/samples/export-from/output/index.d.ts.map

@@ -10,5 +10,5 @@
 	"sourcesContent": [
 		null
 	],
-	"mappings": ";OAAaA,GAAGA"
+	"mappings": ";cAAaA,GAAGA"
 }

test/samples/export-named-as/output/index.d.ts

@@ -2,9 +2,9 @@ declare module 'export-named-as' {
 	/**
 	 * Add two numbers
 	 * */
-	function plus(a: number, b: number): number;
+	export function plus(a: number, b: number): number;
 
-	export { plus };
+	export {};
 }
 
 //# sourceMappingURL=index.d.ts.map

test/samples/export-type/output/index.d.ts

@@ -1,8 +1,8 @@
 declare module 'export-type' {
-	type D = {};
-	class B<D> {}
+	export type D = {};
+	export class B<D> {}
 
-	export { B, D };
+	export {};
 }
 
 //# sourceMappingURL=index.d.ts.map

test/samples/export-type/output/index.d.ts.map

@@ -5,4 +5,4 @@
 	"sources": [],
 	"sourcesContent": [],
 	"mappings": ""
-}
+}