better handling of external modules

src/Bundle.js

@@ -8,13 +8,16 @@ import ExternalModule from './ExternalModule';
 import finalisers from './finalisers/index';
 import replaceIdentifiers from './utils/replaceIdentifiers';
 import makeLegalIdentifier from './utils/makeLegalIdentifier';
+import { defaultResolver } from './utils/resolvePath';
 
 export default class Bundle {
 	constructor ( options ) {
-		this.base = options.base;
-		this.entryPath = resolve( this.base, options.entry );
+		this.base = options.base || process.cwd();
+		this.entryPath = resolve( this.base, options.entry ).replace( /\.js$/, '' ) + '.js';
 		this.entryModule = null;
 
+		this.resolvePath = options.resolvePath || defaultResolver;
+
 		this.modulePromises = {};
 		this.modules = {};
 
@@ -28,9 +31,19 @@ export default class Bundle {
 		this.externalModules = [];
 	}
 
-	fetchModule ( path, id ) {
-		// TODO currently, we'll get different ExternalModule objects
-		// depending on where they're imported from...
+	fetchModule ( importee, importer ) {
+		const path = this.resolvePath( importee, importer );
+
+		if ( !path ) {
+			// external module
+			if ( !has( this.modulePromises, importee ) ) {
+				const module = new ExternalModule( importee );
+				this.externalModules.push( module );
+				this.modulePromises[ importee ] = Promise.resolve( module );
+			}
+
+			return this.modulePromises[ importee ];
+		}
 
 		if ( !has( this.modulePromises, path ) ) {
 			this.modulePromises[ path ] = readFile( path, { encoding: 'utf-8' })
@@ -43,21 +56,6 @@ export default class Bundle {
 
 					this.modules[ path ] = module;
 					return module;
-				}, err => {
-					if ( err.code === 'ENOENT' ) {
-						if ( id[0] === '.' ) {
-							// external modules can't have relative paths
-							throw err;
-						}
-
-						// most likely an external module
-						// TODO fire an event, or otherwise allow some way for
-						// users to control external modules better?
-						const module = new ExternalModule( id );
-
-						this.externalModules.push( module );
-						return module;
-					}
 				});
 		}
 

src/Module.js

@@ -184,9 +184,8 @@ export default class Module {
 		// The definition for this name is in a different module
 		if ( has( this.imports, name ) ) {
 			const importDeclaration = this.imports[ name ];
-			const path = resolve( dirname( this.path ), importDeclaration.source ) + '.js';
 
-			promise = this.bundle.fetchModule( path, importDeclaration.source )
+			promise = this.bundle.fetchModule( importDeclaration.source, this.path )
 				.then( module => {
 					importDeclaration.module = module;
 

src/utils/resolvePath.js

@@ -0,0 +1,11 @@
+import { dirname, isAbsolute, resolve } from 'path';
+
+export function defaultResolver ( importee, importer ) {
+	// absolute paths are left untouched
+	if ( isAbsolute( importee ) ) return importee;
+
+	// external modules stay external
+	if ( importee[0] !== '.' ) return false;
+
+	return resolve( dirname( importer ), importee ).replace( /\.js$/, '' ) + '.js';
+}

test/samples/allows-external-modules-from-nested-module/_config.js

@@ -0,0 +1,3 @@
+module.exports = {
+	description: 'imports external modules from nested internal modules'
+};

test/samples/allows-external-modules-from-nested-module/foo.js

@@ -0,0 +1,6 @@
+import { relative } from 'path';
+
+var path = 'a/b/c';
+var path2 = 'a/c/b';
+
+export default relative( path, path2 );

test/samples/allows-external-modules-from-nested-module/main.js

@@ -0,0 +1,8 @@
+import { relative } from 'path';
+import foo from './foo';
+
+var path = 'foo/bar/baz';
+var path2 = 'foo/baz/bar';
+
+assert.equal( relative( path, path2 ), '../../baz/bar' );
+assert.equal( foo, '../../c/b' );

test/samples/allows-external-modules/_config.js

@@ -1,3 +1,3 @@
 module.exports = {
-	description: 'Non-existent modules are assumed to be external'
+	description: 'Non-absolute and non-relative modules are assumed to be external'
 };

test/samples/export-from-internal-module/_config.js

@@ -2,6 +2,5 @@ module.exports = {
 	description: 'exports from an internal module',
 	exports: function ( exports, assert ) {
 		assert.equal( exports.foo, 42 );
-	},
-	solo: true
+	}
 };