3 files changed, 87 insertions, 2 deletions
diff --git a/src/compiler.js b/src/compiler.js
index 90f05cf0..94085c3f 100644
--- a/src/compiler.js
+++ b/src/compiler.js
@@ -8,7 +8,7 @@ try {
 } catch(e) {}
 
 
-// The environment setup code appears both here and in shell.js, because it can't be shared. Keep them in sync!
+// The environment setup code appears here, in shell.js, and in tests/hello_world.js because it can't be shared. Keep them in sync!
 // *** Environment setup code ***
 var arguments_ = [];
 
diff --git a/tests/hello_world.js b/tests/hello_world.js
new file mode 100644
index 00000000..3fd19d53
--- /dev/null
+++ b/tests/hello_world.js
@@ -0,0 +1,73 @@
+// *** Environment setup code ***
+var arguments_ = [];
+
+var ENVIRONMENT_IS_NODE = typeof process === 'object';
+var ENVIRONMENT_IS_WEB = typeof window === 'object';
+var ENVIRONMENT_IS_SHELL = !ENVIRONMENT_IS_WEB && !ENVIRONMENT_IS_NODE;
+
+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) {
+  printErr = function(x) {
+    console.log(x);
+  };
+
+  read = function(url) {
+    var xhr = new XMLHttpRequest();
+    xhr.open('GET', url, false);
+    xhr.send(null);
+    return xhr.responseText;
+  };
+
+  if (this['arguments']) {
+    arguments_ = arguments;
+  }
+} else {
+  throw 'Unknown runtime environment. Where are we?';
+}
+
+function globalEval(x) {
+  eval.call(null, x);
+}
+
+if (!this['load']) {
+  load = function(f) {
+    globalEval(read(f));
+  };
+}
+// *** Environment setup code ***
+
+print('hello, world!');
+
diff --git a/tests/runner.py b/tests/runner.py
index f1357012..828e5b8e 100644
--- a/tests/runner.py
+++ b/tests/runner.py
@@ -4990,9 +4990,21 @@ else:
 
 if __name__ == '__main__':
   sys.argv = [sys.argv[0]] + ['-v'] + sys.argv[1:] # Verbose output by default
-  # TODO: check for js engines ([] or out of [])
+
+  # Sanity checks
+
+  try:
+    check = run_js(COMPILER_ENGINE, path_from_root('tests', 'hello_world.js'))
+  except Exception, e:
+    check = str(e)
+  if check != 'hello, world!\n':
+    print 'WARNING: The JavaScript shell used for compiling (%s) does not seem to work. Check ~/.emscripten. Output:\n---\n\n%s\n\n---\n' % (str(COMPILER_ENGINE), check)
+
   for cmd in [CLANG, LLVM_DIS]:
     if not os.path.exists(cmd) and not os.path.exists(cmd + '.exe'): # .exe extension required for Windows
       print 'WARNING: Cannot find', cmd
+
+  # Go
+
   unittest.main()