multifile output not creating yaml stream

[achauvin-wish]

I have a jsonnet which outputs a json of the form {out.yaml: [{a:1},{b:2}]} (json simplified for this example).

When I run the command jsonnet -y -m. I do not get the intended yaml stream in the out.yaml file. Instead I get the json format output [{a:1},{b:2}]}.

Is this expected behavior?
I also ran the same command but using jrsonnet (jrsonnet -y -m.) and I obtain the yaml stream as I would expect

[sparkprime]

When you're using multi to output files that are not json (e.g. yaml), you have to choose a format for each file being output. In practice that means using std.exportYamlDoc or std.exportYamlStream to convert the value to a string (use the right function for the format you want) and then using -S when using --multi in order to avoid encoding that string as json.

[johnbartholomew]

Hmm... looking at the code, yaml-stream output and multi-file output is mutually exclusive. I don't think there's a fundamental design reason why they must be so, but that's how the implementation is currently structured. By contrast, the -S flag is handled separately and can be combined with -y or -m.

I think the easiest "fix" here to (mostly) preserve backward compatibility with previous versions of C++ jsonnet would be to report an error if -y and -m are both used. I could do some restructuring to support using them together, but that is more work.