Better compatibility with browserify modules

src/Package.js

@@ -1,16 +1,16 @@
 'use strict';
 
-const isAbsolutePath = require('absolute-path');
 const path = require('./fastpath');
 
 class Package {
 
-  constructor({ file, fastfs, cache }) {
+  constructor({ file, fastfs, cache, replacements = {} }) {
     this.path = file;
     this.root = path.dirname(this.path);
     this._fastfs = fastfs;
     this.type = 'Package';
     this._cache = cache;
+    this.replacements = replacements;
   }
 
   getMain() {
@@ -19,17 +19,14 @@ class Package {
       if (typeof replacements === 'string') {
         return path.join(this.root, replacements);
       }
-
       let main = json.main || 'index';
-
-      if (replacements && typeof replacements === 'object') {
-        main = replacements[main] ||
-          replacements[main + '.js'] ||
-          replacements[main + '.json'] ||
-          replacements[main.replace(/(\.js|\.json)$/, '')] ||
-          main;
+      // cut of the extension, if any
+      main = main.replace(/(\.js|\.json)$/, '');
+      // find a possible replacement
+      var replacement = this.getReplacement(main, replacements);
+      if (replacement !== undefined) {
+        main = replacement;
       }
-
       return path.join(this.root, main);
     });
   }
@@ -50,34 +47,65 @@ class Package {
     this._cache.invalidate(this.path);
   }
 
+  getReplacement(name, replacements) {
+    if (typeof replacements !== 'object') {
+      return undefined;
+    }
+    const relPath = './' + path.relative(this.root, name);
+    const relName = './' + name;
+    const checks = [
+      replacements[name],
+      replacements[name + '.js'],
+      replacements[name + '.json'],
+      replacements[relName],
+      replacements[relName + '.js'],
+      replacements[relName + '.json'],
+      replacements[relPath],
+      replacements[relPath + '.js'],
+      replacements[relPath + '.json'],
+    ];
+    const matches = checks.filter(check => check !== undefined);
+    if (matches[0] === false) {
+      return false;
+    }
+    return matches[0] || undefined;
+  }
+
   redirectRequire(name) {
     return this.read().then(json => {
-      var replacements = getReplacements(json);
-
-      if (!replacements || typeof replacements !== 'object') {
-        return name;
+      let replacements = getReplacements(json);
+      if (typeof replacements === 'string') {
+        replacements = {
+          [json.main || 'index']: replacements,
+        };
       }
-
-      if (name[0] !== '/') {
-        return replacements[name] || name;
+      const replacement = this.getReplacement(name, replacements);
+      // no replacement
+      if (replacement === undefined) {
+        // could stil be requiring a builtin
+        if (this.replacements[name]) {
+          var redirect = path.relative(this.root, this.replacements[name]);
+          // cut off node_modules if the builtin is required
+          // from the "index" of the react-native project
+          if (redirect.slice(0, 13) === 'node_modules/') {
+            redirect = redirect.slice(13);
+          }
+          return redirect;
+        }
+        return name;
       }
-
-      if (!isAbsolutePath(name)) {
-        throw new Error(`Expected ${name} to be absolute path`);
+      // replacement is false boolean
+      if (replacement === false) {
+        // find path to _empty.js
+        const emptyPath = require.resolve('./_empty.js');
+        return './' + path.relative(this.root, emptyPath);
       }
-
-      const relPath = './' + path.relative(this.root, name);
-      const redirect = replacements[relPath] ||
-              replacements[relPath + '.js'] ||
-              replacements[relPath + '.json'];
-      if (redirect) {
-        return path.join(
-          this.root,
-          redirect
-        );
+      // replacement is other module (or absolute path?)
+      if (replacement[0] !== '.') {
+        return replacement;
       }
-
-      return name;
+      // replacement is relative path
+      return path.join(this.root, replacement);
     });
   }
 
@@ -93,7 +121,7 @@ class Package {
 
 function getReplacements(pkg) {
   return pkg['react-native'] == null
-    ? pkg.browser
+    ? (pkg.browser == null ? pkg.browserify : pkg.browser)
     : pkg['react-native'];
 }
 

src/_empty.js

@@ -0,0 +1,8 @@
+/**
+ * Copyright 2013-2015, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */