Add option to configure import.meta.url resolution

docs/999-big-list-of-options.md

@@ -614,14 +614,39 @@ Default: `true`
 
 Whether to `Object.freeze()` namespace import objects (i.e. `import * as namespaceImportObject from...`) that are accessed dynamically.
 
+#### output.importMetaUrl
+Type: `((chunkId: string, moduleId: string) => string)`<br>
+
+This allows the user to configure how Rollup handles `import.meta.url`. In ES modules, `import.meta.url` returns the URL of the current module, e.g. `http://server.net/bundle.js` for browsers or `file:///path/to/bundle.js` in Node.
+
+By default for formats other than ES modules, Rollup replaces `import.meta.url` with code that attempts to match this behaviour by returning the dynamic URL of the current chunk. Note that all formats except CommonJS and UMD assume that they run in a browser environment where `URL` and `document` are available.
+
+ This behaviour can be customized by supplying a function, which will replace `import.meta.url` for all formats:
+
+```javascript
+// rollup.config.js
+export default {
+  ...,
+  output: {
+    ...,
+
+    // this will use the original module id when resolving import.meta.url
+    importMetaUrl(chunkId, moduleId) {
+    	return `"${moduleId}"`;
+    }
+  }
+};
+
+```
+
 #### output.indent
 Type: `boolean | string`<br>
 CLI: `--indent`/`--no-indent`<br>
 Default: `true`
 
 The indent string to use, for formats that require code to be indented (`amd`, `iife`, `umd`, `system`). Can also be `false` (no indent), or `true` (the default – auto-indent)
 
-```js
+```javascript
 // rollup.config.js
 export default {
   ...,

src/Chunk.ts

@@ -800,7 +800,9 @@ export default class Chunk {
 			const module = this.orderedModules[i];
 			const code = this.renderedModuleSources[i];
 			for (const importMeta of module.importMetas) {
-				if (importMeta.renderFinalMechanism(code, this.id, options.format)) usesMechanism = true;
+				if (importMeta.renderFinalMechanism(code, this.id, options.format, options.importMetaUrl)) {
+					usesMechanism = true;
+				}
 			}
 		}
 		return usesMechanism;

src/ast/nodes/MetaProperty.ts

@@ -22,6 +22,7 @@ const importMetaUrlMechanisms: Record<string, (chunkId: string) => string> = {
 			`(require('u' + 'rl').URL)`
 		)} : ${getUrlFromDocument(chunkId)})`,
 	iife: chunkId => getUrlFromDocument(chunkId),
+	system: () => `module.meta.url`,
 	umd: chunkId =>
 		`(typeof document === 'undefined' ? ${getResolveUrl(
 			`'file:' + __filename`,
@@ -68,12 +69,15 @@ export default class MetaProperty extends NodeBase {
 		super.render(code, options);
 	}
 
-	renderFinalMechanism(code: MagicString, chunkId: string, format: string): boolean {
-		if (!this.rendered) return false;
+	renderFinalMechanism(
+		code: MagicString,
+		chunkId: string,
+		format: string,
+		renderImportMetaUrl: ((chunkId: string, moduleId: string) => string) | void
+	): boolean {
+		if (!this.included || !(this.parent instanceof MemberExpression)) return false;
 
-		if (this.parent instanceof MemberExpression === false) return false;
-
-		const parent = <MemberExpression>this.parent;
+		const parent = this.parent;
 
 		let importMetaProperty: string;
 		if (parent.property instanceof Identifier) importMetaProperty = parent.property.name;
@@ -89,12 +93,11 @@ export default class MetaProperty extends NodeBase {
 			return true;
 		}
 
-		if (format === 'system') {
-			code.overwrite(this.meta.start, this.meta.end, 'module');
-		} else if (importMetaProperty === 'url') {
-			const importMetaUrlMechanism = importMetaUrlMechanisms[format];
-			if (importMetaUrlMechanism)
-				code.overwrite(parent.start, parent.end, importMetaUrlMechanism(chunkId));
+		if (importMetaProperty === 'url') {
+			const getImportMetaUrl = renderImportMetaUrl || importMetaUrlMechanisms[format];
+			if (getImportMetaUrl) {
+				code.overwrite(parent.start, parent.end, getImportMetaUrl(chunkId, this.context.module.id));
+			}
 			return true;
 		}
 

src/rollup/types.d.ts

@@ -315,6 +315,7 @@ export interface OutputOptions {
 	format?: ModuleFormat;
 	freeze?: boolean;
 	globals?: GlobalsOption;
+	importMetaUrl?: (chunkId: string, moduleId: string) => string;
 	indent?: boolean;
 	interop?: boolean;
 	intro?: string | (() => string | Promise<string>);

src/utils/mergeOptions.ts

@@ -248,6 +248,7 @@ function getOutputOptions(
 		format: format === 'esm' ? 'es' : format,
 		freeze: getOption('freeze', true),
 		globals: getOption('globals'),
+		importMetaUrl: getOption('importMetaUrl'),
 		indent: getOption('indent', true),
 		interop: getOption('interop', true),
 		intro: getOption('intro'),

test/form/samples/configure-import-meta-url/_config.js

@@ -0,0 +1,13 @@
+module.exports = {
+	description: 'allows to configure import.meta.url',
+	options: {
+		output: {
+			importMetaUrl(chunkId, moduleId) {
+				return `'${chunkId}/${moduleId
+					.split('/')
+					.slice(-2)
+					.join('/')}'`;
+			}
+		}
+	}
+};

test/form/samples/configure-import-meta-url/_expected/amd.js

@@ -0,0 +1,5 @@
+define(['module'], function (module) { 'use strict';
+
+	console.log('amd.js/configure-import-meta-url/main.js');
+
+});

test/form/samples/configure-import-meta-url/_expected/cjs.js

@@ -0,0 +1,3 @@
+'use strict';
+
+console.log('cjs.js/configure-import-meta-url/main.js');

test/form/samples/configure-import-meta-url/_expected/es.js

@@ -0,0 +1 @@
+console.log('es.js/configure-import-meta-url/main.js');

test/form/samples/configure-import-meta-url/_expected/iife.js

@@ -0,0 +1,6 @@
+(function () {
+	'use strict';
+
+	console.log('iife.js/configure-import-meta-url/main.js');
+
+}());

test/form/samples/configure-import-meta-url/_expected/system.js

@@ -0,0 +1,10 @@
+System.register([], function (exports, module) {
+	'use strict';
+	return {
+		execute: function () {
+
+			console.log('system.js/configure-import-meta-url/main.js');
+
+		}
+	};
+});

test/form/samples/configure-import-meta-url/_expected/umd.js

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

test/form/samples/configure-import-meta-url/main.js

@@ -0,0 +1 @@
+console.log(import.meta.url);