Cannot use -f with source file from stdin

I have a long series of commands I'd like to run on some BUILD file text. The commands sometimes have different targets, so I can't pass the commands on the commandline. I tried writing my commands to a temp file, and then using `-f`. In the file, I use `-:__pkg__` to operate on stdin. However, I get this error:

```
-/BUILD: file not found or not readable
```

It seems that `-` is not recognized in a command file.

Start by reproducing the issue with a command file passed via `-f` and a BUILD file supplied on stdin, using the `-:__pkg__` marker described in the report. Trace how command-file arguments and the `-` source are parsed; done means the command runs against stdin without looking for `-/BUILD`.

Written by the indexing model from the issue text.