core: throw TypeError if chdir() args are wrong

PR-URL: https://github.com/iojs/io.js/pull/274
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>

src/node.cc

@@ -1499,8 +1499,7 @@ static void Chdir(const FunctionCallbackInfo<Value>& args) {
   Environment* env = Environment::GetCurrent(args);
 
   if (args.Length() != 1 || !args[0]->IsString()) {
-    // FIXME(bnoordhuis) ThrowTypeError?
-    return env->ThrowError("Bad argument.");
+    return env->ThrowTypeError("Bad argument.");
   }
 
   node::Utf8Value path(args.GetIsolate(), args[0]);

test/sequential/test-chdir.js

@@ -38,3 +38,7 @@ assert(process.cwd() == dir);
 process.chdir('..');
 assert(process.cwd() == path.resolve(common.fixturesDir));
 fs.rmdirSync(dir);
+
+assert.throws(function() { process.chdir({}); }, TypeError, 'Bad argument.');
+assert.throws(function() { process.chdir(); }, TypeError, 'Bad argument.');
+assert.throws(function() { process.chdir("x", "y"); }, TypeError, 'Bad argument.');