UX: Command arguments are order sensitive

[jepperson2]

What were you trying to do

Decrypt using a custom key.

What happened

I received an error stating too many arguments. The problem seemed to be that I had the -d <filename> before the -i <filename>. Reversing these two arguments caused age to behave as I expected.

The error message as stated made me think the problem was in the -i <filename> component of the command as it just says "input file", but I think the problem was that it tried to keep reading more files for the -d parameter when I expected it to stop and go on to the -i parameter input.

$ age -d test.age -i ~/.config/age/keys.txt
Error: too many arguments.
age accepts a single optional argument for the input file.
[ Did age not do what you expected? Could an error be more useful? Tell us: https://filippo.io/age/report ]

$ age -i ~/.config/age/keys.txt -d test.age
hello there

[FiloSottile]

Thank you for reporting this!

What's going on is that -d is not a flag that takes an argument, just a switch, and the input file is an argument so has to go after the flags.

It's a little tricky because the input file is optional, but sounds like we should make this better.

[sylr]

Using github.com/spf13/pflag instead of the standard flag package should help.

[FiloSottile]

Better error messages for this is tracked as #160.