Help for Metapost builder

[dlefur]

Hello,
I try to create a Metapost builder.
The command “mpost filename.mp” will create one or more figures named “filename.1”, “filename.2”, …
Another option is to use the command “mptopdf filename.mp” which creates one or more figures named “filename-1.pdf”, “filename-1.pdf”, …

At this point, I managed to create a Metapost.sublime-build file :

{	
    "cmd": ["mptopdf",  "$file"],
    "working_dir": "$file_path",
    "selector": "text.metapost"
}

I don’t know how to improve it to get Sublime to view the pdf outputs, if possible, in one unique file …

Thanks for any help !