esperanto - npm Package Compare versions

Comparing version 0.6.29 to 0.6.30

CHANGELOG.md

 # changelog
 
+## 0.6.30
+
+* Mutually dependent modules within a bundle are re-ordered based on whether one is referenced at the top level of the other ([#152](https://github.com/esperantojs/esperanto/issues/152))
+
 ## 0.6.29
@@ -4,0 +8,0 @@

package.json

 {
   "name": "esperanto",
   "description": "An easier way to convert ES6 modules to AMD and CommonJS",
-  "version": "0.6.29",
+  "version": "0.6.30",
   "author": "Rich Harris",
@@ -6,0 +6,0 @@ "repository": "https://github.com/esperantojs/esperanto",

src/bundler/getBundle.js

@@ -31,3 +31,3 @@ import path from 'path';
 			let entryModule = moduleLookup[ entry ];
-			modules = sortModules( entryModule, moduleLookup ); // TODO is this necessary? surely it's already sorted because of the fetch order? or do we need to prevent parallel reads?
+			modules = sortModules( entryModule, moduleLookup );
 
@@ -34,0 +34,0 @@ let bundle = {

src/bundler/utils/sortModules.js

 import hasOwnProp from 'utils/hasOwnProp';
+import walk from 'utils/ast/walk';
 
 export default function sortModules ( entry, moduleLookup ) {
-	var seen = {},
-		ordered = [];
+	let seen = {};
+	let ordered = [];
+	let swapPairs = [];
 
 	function visit ( mod ) {
-		// ignore external modules, and modules we've
-		// already included
-		if ( !mod || hasOwnProp.call( seen, mod.id ) ) {
-			return;
-		}
-
 		seen[ mod.id ] = true;
 
 		mod.imports.forEach( x => {
-			visit( moduleLookup[ x.id ] );
+			const imported = moduleLookup[ x.id ];
+
+			if ( !imported ) return;
+
+			// ignore modules we've already included
+			if ( hasOwnProp.call( seen, imported.id ) ) {
+				if ( shouldSwap( imported, mod ) ) {
+					swapPairs.push([ imported, mod ]);
+				}
+
+				return;
+			}
+
+			visit( imported );
 		});
@@ -25,3 +34,60 @@
 
+	swapPairs.forEach( ([ a, b ]) => {
+		const aIndex = ordered.indexOf( a );
+		const bIndex = ordered.indexOf( b );
+
+		ordered[ aIndex ] = b;
+		ordered[ bIndex ] = a;
+	});
+
 	return ordered;
 }
+
+function shouldSwap ( a, b ) {
+	// if these modules don't import each other, abort
+	if ( !( imports( a, b ) && imports( b, a ) ) ) return;
+
+	return usesAtTopLevel( b, a ) && !usesAtTopLevel( a, b );
+}
+
+function imports ( a, b ) {
+	let i = a.imports.length;
+	while ( i-- ) {
+		if ( a.imports[i].id === b.id ) {
+			return true;
+		}
+	}
+}
+
+function usesAtTopLevel ( a, b ) {
+	let bindings = [];
+
+	// find out which bindings a imports from b
+	let i = a.imports.length;
+	while ( i-- ) {
+		if ( a.imports[i].id === b.id ) {
+			bindings.push.apply( bindings, a.imports[i].specifiers.map( x => x.as ) );
+		}
+	}
+
+	// see if any of those bindings are referenced at the top level
+	let referencedAtTopLevel = false;
+
+	walk( a.ast, {
+		enter ( node ) {
+			if ( referencedAtTopLevel ) {
+				return this.skip();
+			}
+
+			if ( /^Import/.test( node.type ) || ( node._scope && node._scope.parent ) ) {
+				return this.skip();
+			}
+
+			if ( node.type === 'Identifier' && ~bindings.indexOf( node.name ) ) {
+				referencedAtTopLevel = true;
+			}
+		}
+	});
+
+	return referencedAtTopLevel;
+}

src/utils/ast/findImportsAndExports.js

@@ -81,4 +81,2 @@ /**
 		specifiers: node.specifiers.map( s => {
-			var id;
-
 			if ( s.type === 'ImportNamespaceSpecifier' ) {
@@ -97,3 +95,3 @@ return {
 					as: s.local.name
-				}
+				};
 			}
@@ -100,0 +98,0 @@

src/utils/ast/rewriteExportAssignments.js

@@ -38,3 +38,3 @@ import hasOwnProp from 'utils/hasOwnProp';
 				if ( !node.prefix ) {
-					suffix += `, ${name} ${node.operator === '++' ? '-' : '+'} 1`
+					suffix += `, ${name} ${node.operator === '++' ? '-' : '+'} 1`;
 				}
@@ -41,0 +41,0 @@ prefix += `( `;

No alert changes

Improved metrics

Total package byte prevSize

238232

increased by1.19%

Lines of code

6795

increased by1.45%

No dependency changes