enable required for positionals about argparse HOT 5 OPEN

I'm not sure if this belongs here, or could be considered a separate issue:

I'm using argparse with 3 (required) positional args and 1 optional arg. If you don't pass any args to the program, error is nil and program execution continues (and eventually causes errors when trying to access non existent files):

parser := argparse.NewParser("", "blahblahblah")
var inFile *os.File = parser.FilePositional(os.O_RDONLY, 0600, &argparse.Options{Required: true, Help: "..."})
var outFilename *string = parser.StringPositional(&argparse.Options{Required: true, Help: "..."})
var configFile *os.File = parser.FilePositional(os.O_RDONLY, 0600, &argparse.Options{Required: true, Help: "..."})
startAtFileRow := parser.Int("r", "rowstart", &argparse.Options{Default: 1, Required: false, Help: "..."})

err := parser.Parse(os.Args)
if err != nil {
     log.Fatal(parser.Usage(err))
}

When I push this to a server for use by other users, most of them will naively execute it w/out any args nor even passing "-h" with the expectation that it will show them which arguments are required. In this scenario, the program just explodes:
$ ./asset-migrator
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x4b63b1]
...

from argparse.

@ryansch80 That sounds as a bug that needs to be assessed and fixed.

Yes, that seems to be related, if I understand top post correctly required currently ignored.

As a workaround until this is fixed you could add a check of positional values and throw an error if they are not provided.

from argparse.

@vsachs Thanks, I think we do need to enable Required to work for positionals. I generally agree with all requirements except for:

Do not throw an error if there are Required positionals on commands which did not Happen

I think if positional is marked as required and there is no value available to fill it -- should throw an error.

I would probably say that as per #108 (comment) it should be considered a bug rather than an enhancement.

from argparse.

I think if positional is marked as required and there is no value available to fill it -- should throw an error.

If we always throw an error when a required is unsatisfied, then if someone creates multiple sub-commands all of which have a required positional, the argparser will always error. There will be no way for one sub-command to "take precedence". I think that's not a good system but it's up for discussion of course.

it should be considered a bug rather than an enhancement.
Sure, that's fine I guess.

I'll try to take a couple moments next week to fix this. I'm working on Nargs as well but I got pulled away from it.

from argparse.

I see these issues and comments are older. Are you still maintaining this repo and accepting PRs?

from argparse.