basic export handling

src/Bundle.js

@@ -4,8 +4,10 @@ import MagicString from 'magic-string';
 import { keys, has } from './utils/object';
 import { sequence } from './utils/promise';
 import Module from './Module';
+import ExternalModule from './ExternalModule';
 import finalisers from './finalisers/index';
 import replaceIdentifiers from './utils/replaceIdentifiers';
+import makeLegalIdentifier from './utils/makeLegalIdentifier';
 
 export default class Bundle {
 	constructor ( options ) {
@@ -27,6 +29,9 @@ export default class Bundle {
 	}
 
 	fetchModule ( path, id ) {
+		// TODO currently, we'll get different ExternalModule objects
+		// depending on where they're imported from...
+
 		if ( !has( this.modulePromises, path ) ) {
 			this.modulePromises[ path ] = readFile( path, { encoding: 'utf-8' })
 				.then( code => {
@@ -48,11 +53,7 @@ export default class Bundle {
 						// most likely an external module
 						// TODO fire an event, or otherwise allow some way for
 						// users to control external modules better?
-						const module = {
+						const module = new ExternalModule( id );
-							id,
-							isExternal: true,
-							specifiers: []
-						};
 
 						this.externalModules.push( module );
 						return module;
@@ -63,14 +64,6 @@ export default class Bundle {
 		return this.modulePromises[ path ];
 	}
 
-	getBindingNamesFor ( module ) {
-		if ( !has( this.bindingNames, module.path ) ) {
-			this.bindingNames[ module.path ] = {};
-		}
-
-		return this.bindingNames[ module.path ];
-	}
-
 	build () {
 		// bring in top-level AST nodes from the entry module
 		return this.fetchModule( this.entryPath )
@@ -108,6 +101,18 @@ export default class Bundle {
 	}
 
 	deconflict () {
+		// TODO this probably needs to happen at generate time, since
+		// treatment of external modules differs between formats
+		// e.g. this...
+		//
+		//     import { relative } from 'path'`;
+		//     console.log( relative( 'foo', 'bar' ) );
+		//
+		// ...would look very similar when bundled as ES6, but in
+		// a CommonJS bundle would become this:
+		//
+		//     var path = require( 'path' );
+		//     console.log( path.relative( 'foo', 'bar' ) );
 		let definers = {};
 		let conflicts = {};
 
@@ -126,6 +131,17 @@ export default class Bundle {
 			});
 		});
 
+		// Assign names to external modules
+		this.externalModules.forEach( module => {
+			let name = makeLegalIdentifier( module.id );
+
+			while ( has( definers, name ) ) {
+				name = `_${name}`;
+			}
+
+			module.name = name;
+		});
+
 		// Rename conflicting identifiers so they can live in the same scope
 		keys( conflicts ).forEach( name => {
 			const modules = definers[ name ];
@@ -156,12 +172,27 @@ export default class Bundle {
 	}
 
 	generate ( options = {} ) {
-		let magicString = new MagicString.Bundle();
+		let magicString = new MagicString.Bundle({ separator: '' });
 
-		this.body.forEach( statement => {
+		this.entryModule.exportStatements.forEach( statement => {
-			const module = statement._module;
+			if ( statement.specifiers.length ) {
+				// we don't need to include `export { foo }`, it's already handled
+				return;
+			}
 
-			replaceIdentifiers( statement, statement._source, module.nameReplacements );
+			if ( statement.declaration.type === 'VariableDeclaration' ) {
+				const declarator = statement.declaration.declarations[0];
+				statement._source.remove( statement.start, statement.declaration.start );
+			} else {
+				// TODO function, class declarations
+			}
+
+			// TODO are there situations where the export needs to be
+			// placed higher up, i.e. kept in situ? probably...
+			this.body.push( statement );
+		});
+
+		this.body.forEach( statement => {
 			magicString.addSource( statement._source );
 		});
 

src/ExternalModule.js

@@ -0,0 +1,33 @@
+import { has } from './utils/object';
+
+export default class ExternalModule {
+	constructor ( id ) {
+		this.id = id;
+		this.name = null;
+
+		this.isExternal = true;
+		this.importedByBundle = [];
+
+		this.canonicalNames = {};
+		this.defaultExportName = null;
+	}
+
+	getCanonicalName ( name ) {
+		if ( name === 'default' ) {
+			return `${this.name}__default`; // TODO...
+		}
+
+		// TODO this depends on the output format... works for CJS etc but not ES6
+		return `${this.name}.${name}`;
+	}
+
+	rename ( name, replacement ) {
+		this.canonicalNames[ name ] = replacement;
+	}
+
+	suggestDefaultName ( name ) {
+		if ( !this.defaultExportName ) {
+			this.defaultExportName = name;
+		}
+	}
+}

src/Module.js

@@ -28,7 +28,6 @@ export default class Module {
 
 		this.definedNames = this.ast._scope.names.slice();
 
-		this.nameReplacements = {};
 		this.canonicalNames = {};
 
 		this.definitions = {};
@@ -49,9 +48,13 @@ export default class Module {
 			});
 		});
 
+		// imports and exports, indexed by ID
 		this.imports = {};
 		this.exports = {};
 
+		// an array of export statements, used for the entry module
+		this.exportStatements = [];
+
 		this.ast.body.forEach( node => {
 			// import foo from './foo';
 			// import { bar } from './bar';
@@ -59,29 +62,34 @@ export default class Module {
 				const source = node.source.value;
 
 				node.specifiers.forEach( specifier => {
-					const name = specifier.local.name;
 					const isDefault = specifier.type === 'ImportDefaultSpecifier';
+					const isNamespace = specifier.type === 'ImportNamespaceSpecifier';
+
+					const localName = specifier.local.name;
+					const name = isDefault ? 'default' : isNamespace ? '*' : specifier.imported.name;
 
-					this.imports[ name ] = {
+					this.imports[ localName ] = {
 						source,
-						name: isDefault ? 'default' : specifier.imported.name,
+						name,
-						localName: name
+						localName
 					};
 				});
 			}
 
+			else if ( /^Export/.test( node.type ) ) {
+				this.exportStatements.push( node );
+
 				// export default function foo () {}
 				// export default foo;
 				// export default 42;
-			else if ( node.type === 'ExportDefaultDeclaration' ) {
+				if ( node.type === 'ExportDefaultDeclaration' ) {
 					const isDeclaration = /Declaration$/.test( node.declaration.type );
 
 					this.exports.default = {
 						node,
 						name: 'default',
 						localName: isDeclaration ? node.declaration.id.name : 'default',
-					isDeclaration,
+						isDeclaration
-					module: null // filled in later
 					};
 				}
 
@@ -96,7 +104,8 @@ export default class Module {
 							const exportedName = specifier.exported.name;
 
 							this.exports[ exportedName ] = {
-							localName
+								localName,
+								exportedName
 							};
 						});
 					}
@@ -115,11 +124,13 @@ export default class Module {
 						}
 
 						this.exports[ name ] = {
+							node,
 							localName: name,
 							expression: declaration
 						};
 					}
 				}
+			}
 		});
 	}
 
@@ -128,10 +139,16 @@ export default class Module {
 			const importDeclaration = this.imports[ name ];
 			const module = importDeclaration.module;
 
-			// TODO handle external modules
+			let exporterLocalName;
+
+			if ( module.isExternal ) {
+				exporterLocalName = name;
+			} else {
 				const exportDeclaration = module.exports[ importDeclaration.name ];
+				exporterLocalName = exportDeclaration.localName;
+			}
 
-			return module.getCanonicalName( exportDeclaration.localName );
+			return module.getCanonicalName( exporterLocalName );
 		}
 
 		if ( name === 'default' ) {
@@ -156,23 +173,23 @@ export default class Module {
 
 			promise = this.bundle.fetchModule( path, importDeclaration.source )
 				.then( module => {
+					importDeclaration.module = module;
+
+					if ( importDeclaration.name === 'default' ) {
+						module.suggestDefaultName( importDeclaration.localName );
+					}
+
 					if ( module.isExternal ) {
-						module.specifiers.push( importDeclaration );
+						module.importedByBundle.push( importDeclaration );
 						return emptyArrayPromise;
 					}
 
-					importDeclaration.module = module;
-
 					const exportDeclaration = module.exports[ importDeclaration.name ];
 
 					if ( !exportDeclaration ) {
 						throw new Error( `Module ${module.path} does not export ${importDeclaration.name} (imported by ${this.path})` );
 					}
 
-					if ( importDeclaration.name === 'default' ) {
-						module.suggestDefaultName( importDeclaration.localName );
-					}
-
 					return module.define( exportDeclaration.localName );
 				});
 		}

src/finalisers/cjs.js

@@ -1,11 +1,32 @@
+import { keys } from '../utils/object';
+import makeLegalIdentifier from '../utils/makeLegalIdentifier';
+
 export default function cjs ( bundle, magicString, options ) {
-	const intro = `'use strict';\n\n`;
+	let intro = `'use strict';\n\n`;
+
+	// TODO handle ambiguous default imports
+	// TODO handle empty imports, once they're supported
+	const importBlock = bundle.externalModules
+		.map( module => `var ${module.name} = require('${module.id}');` )
+		.join( '\n' );
+
+	if ( importBlock ) {
+		intro += importBlock + '\n\n';
+	}
+
+	magicString.prepend( intro );
+
+	// TODO handle default exports
+	const exportBlock = keys( bundle.entryModule.exports )
+		.map( key => {
+			const specifier = bundle.entryModule.exports[ key ];
+			return `exports.${key} = ${specifier.localName}`;
+		})
+		.join( '\n' );
 
-	// TODO group modules more intelligently
+	if ( exportBlock ) {
-	bundle.externalModules.forEach( module => {
+		magicString.append( '\n\n' + exportBlock );
-		console.log( 'module', module );
+	}
-		//intro += `var
-	});
 
-	return magicString.prepend( intro );
+	return magicString;
 }

src/utils/makeLegalIdentifier.js

@@ -0,0 +1,6 @@
+export default function makeLegalIdentifier ( str ) {
+	str = str.replace( /[^$_a-zA-Z0-9]/g, '_' );
+	if ( /\d/.test( str[0] ) ) str = `_${str}`;
+
+	return str;
+}

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

@@ -0,0 +1,3 @@
+module.exports = {
+	description: 'Non-existent modules are assumed to be external'
+};

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

@@ -0,0 +1,6 @@
+import { relative } from 'path';
+
+var path = 'foo/bar/baz';
+var path2 = 'foo/baz/bar';
+
+assert.equal( relative( path, path2 ), '../../baz/bar' );

test/samples/exports-named-values/_config.js

@@ -0,0 +1,6 @@
+module.exports = {
+	description: 'exports named values from the bundle entry module',
+	exports: function ( exports, assert ) {
+		assert.equal( exports.answer, 42 );
+	}
+};

test/samples/exports-named-values/main.js

@@ -0,0 +1 @@
+export var answer = 42;

test/test.js

@@ -30,8 +30,13 @@ describe( 'rollup', function () {
 					});
 
 					try {
-						var fn = new Function( 'assert', result.code );
+						var fn = new Function( 'require', 'exports', 'assert', result.code );
-						fn( assert );
+						var exports = {};
+						fn( require, exports, assert );
+
+						if ( config.exports ) {
+							config.exports( exports, assert );
+						}
 					} catch ( err ) {
 						console.log( result.code );
 						throw err;