JSX tool return zero on error

[arsfeld]

I'm using the JSX tool in an automated build system and I want to check for errors compiling JSX files, but instead of returning a non-zero error code, the jsx command just writes everything to stderr and exits with a zero error code.
What is even worse, stderr is used when the build is successfull as well, forcing me to parse it's stderr output to check for an error.

[zpao]

Good point! We use an intermediate tool that does caching and some other smart things. I'm going to pass this off to @benjamn because he's the author of commoner.