refactor js optimizer to not use fs.* as much as possible

1 files changed, 89 insertions, 12 deletions

diff --git a/tools/js-optimizer.js b/tools/js-optimizer.js
index 7ac2195f..a77e0e09 100644
--- a/tools/js-optimizer.js
+++ b/tools/js-optimizer.js
@@ -5,26 +5,103 @@
 //  conjunction with closure compiler.
 //==============================================================================
 
-var uglify = require('../tools/eliminator/node_modules/uglify-js');
-var fs = require('fs');
+// *** Environment setup code ***
+var arguments_ = [];
+
+var ENVIRONMENT_IS_NODE = typeof process === 'object';
+var ENVIRONMENT_IS_WEB = typeof window === 'object';
+var ENVIRONMENT_IS_WORKER = typeof importScripts === 'function';
+var ENVIRONMENT_IS_SHELL = !ENVIRONMENT_IS_WEB && !ENVIRONMENT_IS_NODE && !ENVIRONMENT_IS_WORKER;
+
+if (ENVIRONMENT_IS_NODE) {
+  // Expose functionality in the same simple way that the shells work
+  print = function(x) {
+    process['stdout'].write(x + '\n');
+  };
+  printErr = function(x) {
+    process['stderr'].write(x + '\n');
+  };
+
+  var nodeFS = require('fs');
+
+  read = function(filename) {
+    var ret = nodeFS['readFileSync'](filename).toString();
+    if (!ret && filename[0] != '/') {
+      filename = __dirname.split('/').slice(0, -1).join('/') + '/src/' + filename;
+      ret = nodeFS['readFileSync'](filename).toString();
+    }
+    return ret;
+  };
+
+  arguments_ = process['argv'].slice(2);
+
+} else if (ENVIRONMENT_IS_SHELL) {
+  // Polyfill over SpiderMonkey/V8 differences
+  if (!this['read']) {
+    read = function(f) { snarf(f) };
+  }
+
+  if (!this['arguments']) {
+    arguments_ = scriptArgs;
+  } else {
+    arguments_ = arguments;
+  }
+
+} else if (ENVIRONMENT_IS_WEB) {
+  print = printErr = function(x) {
+    console.log(x);
+  };
 
-// Make node environment compatible with JS shells
+  read = function(url) {
+    var xhr = new XMLHttpRequest();
+    xhr.open('GET', url, false);
+    xhr.send(null);
+    return xhr.responseText;
+  };
 
-function print(text) {
-  process.stdout.write(text + '\n');
+  if (this['arguments']) {
+    arguments_ = arguments;
+  }
+} else if (ENVIRONMENT_IS_WORKER) {
+  // We can do very little here...
+
+  load = importScripts;
+
+} else {
+  throw 'Unknown runtime environment. Where are we?';
+}
+
+function globalEval(x) {
+  eval.call(null, x);
+}
+
+if (typeof load == 'undefined' && typeof read != 'undefined') {
+  load = function(f) {
+    globalEval(read(f));
+  };
 }
-function printErr(text) {
-  process.stderr.write(text + '\n');
+
+if (typeof printErr === 'undefined') {
+  printErr = function(){};
+}
+
+if (typeof print === 'undefined') {
+  print = printErr;
 }
-function read(filename) {
+// *** Environment setup code ***
+
+// Fix read for our location
+read = function(filename) {
   if (filename[0] != '/') filename = __dirname.split('/').slice(0, -1).join('/') + '/src/' + filename;
   return fs.readFileSync(filename).toString();
 }
-var arguments = process.argv.slice(2);
+
+var uglify = require('../tools/eliminator/node_modules/uglify-js');
+var fs = require('fs');
 
 // Load some modules
 
-eval(read('utility.js'));
+load('utility.js');
 
 // Utilities
 
@@ -1030,14 +1107,14 @@ var passes = {
 
 // Main
 
-var src = fs.readFileSync('/dev/stdin').toString();
+var src = read(arguments_[0]);
 var ast = srcToAst(src);
 //printErr(JSON.stringify(ast)); throw 1;
 var metadata = src.split('\n').filter(function(line) { return line.indexOf('EMSCRIPTEN_GENERATED_FUNCTIONS') >= 0 })[0];
 //assert(metadata, 'Must have EMSCRIPTEN_GENERATED_FUNCTIONS metadata');
 if (metadata) setGeneratedFunctions(metadata);
 
-arguments.forEach(function(arg) {
+arguments_.slice(1).forEach(function(arg) {
   passes[arg](ast);
 });
 //printErr('output: ' + dump(ast));