From a84db65990cc064e407c9496914002c6b6048512 Mon Sep 17 00:00:00 2001
From: Christian Tellnes <christian@tellnes.no>
Date: Mon, 7 Dec 2015 03:06:38 +0100
Subject: [PATCH] Expose `require` before initializing entries

---
 index.js         | 15 ++++++++++-----
 prelude.js       | 12 ++++++++----
 test/external.js | 43 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 61 insertions(+), 9 deletions(-)
 create mode 100644 test/external.js

diff --git a/index.js b/index.js
index 9d3ab70..6425351 100644
--- a/index.js
+++ b/index.js
@@ -46,10 +46,6 @@ module.exports = function (opts) {
             var pre = umd.prelude(opts.standalone).trim();
             stream.push(Buffer(pre + 'return '));
         }
-        else if (first && stream.hasExports) {
-            var pre = opts.externalRequireName || 'require';
-            stream.push(Buffer(pre + '='));
-        }
         if (first) stream.push(Buffer(prelude + '({'));
         
         if (row.sourceFile && !row.nomap) {
@@ -96,7 +92,16 @@ module.exports = function (opts) {
         if (first) stream.push(Buffer(prelude + '({'));
         entries = entries.filter(function (x) { return x !== undefined });
         
-        stream.push(Buffer('},{},' + JSON.stringify(entries) + ')'));
+        var postlude = [
+            '}',
+            '{}',
+            JSON.stringify(entries),
+            'this', // this === window
+            stream.hasExports ? 'true' : 'false',
+            JSON.stringify(opts.externalRequireName || 'require')
+        ].join(',');
+
+        stream.push(Buffer(postlude + ')'));
 
         if (opts.standalone && !first) {
             stream.push(Buffer(
diff --git a/prelude.js b/prelude.js
index d291c69..b54239f 100644
--- a/prelude.js
+++ b/prelude.js
@@ -7,9 +7,9 @@
 // anything defined in a previous bundle is accessed via the
 // orig method which is the requireuire for previous bundles
 
-(function outer (modules, cache, entry) {
+(function outer (modules, cache, entry, global, hasExports, erName) {
     // Save the require from previous bundle to this closure if any
-    var previousRequire = typeof require == "function" && require;
+    var previousRequire = typeof global[erName] === "function" && global[erName];
 
     function newRequire(name, jumped){
         if(!cache[name]) {
@@ -17,7 +17,7 @@
                 // if we cannot find the module within our internal map or
                 // cache jump to the current global require ie. the last bundle
                 // that was added to the page.
-                var currentRequire = typeof require == "function" && require;
+                var currentRequire = typeof global[erName] === "function" && global[erName];
                 if (!jumped && currentRequire) return currentRequire(name, true);
 
                 // If there are other bundles on this page the require from the
@@ -37,8 +37,12 @@
         }
         return cache[name].exports;
     }
+
+    // Override the current require with this new one. This has to happend
+    // before we requires anything so cross bundle requiring works both ways.
+    if (hasExports) global[erName] = newRequire;
+
     for(var i=0;i<entry.length;i++) newRequire(entry[i]);
 
-    // Override the current require with this new one
     return newRequire;
 })
diff --git a/test/external.js b/test/external.js
new file mode 100644
index 0000000..46d64dd
--- /dev/null
+++ b/test/external.js
@@ -0,0 +1,43 @@
+var vm = require('vm');
+var test = require('tap').test;
+var pack = require('../');
+
+test('external modules', function (t) {
+    t.plan(1);
+
+    var p1 = pack({ raw: true, hasExports: true });
+    var p2 = pack({ raw: true, hasExports: true });
+
+    var s1 = '';
+    var s2 = '';
+    p1.on('data', function (buf) { s1 += buf });
+    p2.on('data', function (buf) { s2 += buf });
+    p2.on('end', function () {
+        var context = vm.createContext({ });
+        vm.runInContext('require=' + s1, context);
+        vm.runInContext('require=' + s2, context);
+        t.equal(context.require('foo'), 'hello');
+        t.end();
+    });
+
+    p2.write({
+        id: 'foo',
+        source: 'module.exports = require("./bar")',
+        deps: { './bar': 'bar' },
+        entry: true
+    });
+
+    p1.write({
+        id: 'bar',
+        source: 'module.exports = require("./baz")',
+        deps: { './baz': 'baz' }
+    });
+
+    p2.write({
+        id: 'baz',
+        source: 'module.exports = "hello"'
+    });
+
+    p1.end();
+    p2.end();
+});