bin_name overrides name in the help message

[sphynx]

Maintainer's notes

• Fixing this might also fix Subcommand name without hyphen in help #1431 and the --version flag concatenates subcommands #1382

---

Rust Version

rustc 1.36.0-nightly (af98304b9 2019-05-11)

Affected Version of clap

2.33

Bug or Feature Request Summary

If I use bin_name to override executable name in usage (for something like cargo command), clap also automatically overrides name (as well as argument to App::new) in the help message. It would be nice to have control over the name, since it appears at the very top of the help message.

Expected Behavior Summary

> cargo run -- --help
appname

USAGE:
    bin name

Actual Behavior Summary

> cargo run -- --help
bin-name

USAGE:
    bin name

Steps to Reproduce the issue

cargo run -- --help

Sample Code or Link to Sample Code

use clap::App;

fn main() {
    App::new("My Super Program")
        .name("appname")
        .bin_name("bin name")
        .get_matches();
}

Debug output

Debug Output

DEBUG:clap:Parser::propagate_settings: self=appname, g_settings=AppFlags(

(empty),

)

DEBUG:clap:Parser::get_matches_with;

DEBUG:clap:Parser::create_help_and_version;

DEBUG:clap:Parser::create_help_and_version: Building --help

DEBUG:clap:Parser::create_help_and_version: Building --version

DEBUG:clap:Parser::get_matches_with: Begin parsing '"--help"' ([45, 45, 104, 101, 108, 112])

DEBUG:clap:Parser::is_new_arg:"--help":NotFound

DEBUG:clap:Parser::is_new_arg: arg_allows_tac=false

DEBUG:clap:Parser::is_new_arg: -- found

DEBUG:clap:Parser::is_new_arg: starts_new_arg=true

DEBUG:clap:Parser::possible_subcommand: arg="--help"

DEBUG:clap:Parser::get_matches_with: possible_sc=false, sc=None

DEBUG:clap:ArgMatcher::process_arg_overrides:None;

DEBUG:clap:Parser::parse_long_arg;

DEBUG:clap:Parser::parse_long_arg: Does it contain '='...No

DEBUG:clap:Parser::parse_long_arg: Found valid flag '--help'

DEBUG:clap:Parser::check_for_help_and_version_str;

DEBUG:clap:Parser::check_for_help_and_version_str: Checking if --help is help or version...Help

DEBUG:clap:Parser::_help: use_long=true

DEBUG:clap:Help::write_parser_help;

DEBUG:clap:Help::write_parser_help;

DEBUG:clap:Parser::color;

DEBUG:clap:Parser::color: Color setting...Auto

DEBUG:clap:is_a_tty: stderr=false

DEBUG:clap:Help::new;

DEBUG:clap:Help::write_help;

DEBUG:clap:Help::write_default_help;

DEBUG:clap:Help::write_bin_name;

DEBUG:clap:Help::write_version;

DEBUG:clap:usage::create_usage_no_title;

DEBUG:clap:usage::get_required_usage_from: reqs=[], extra=None

DEBUG:clap:usage::get_required_usage_from: after init desc_reqs=[]

DEBUG:clap:usage::get_required_usage_from: no more children

DEBUG:clap:usage::get_required_usage_from: final desc_reqs=[]

DEBUG:clap:usage::get_required_usage_from: args_in_groups=[]

DEBUG:clap:usage::needs_flags_tag;

DEBUG:clap:usage::needs_flags_tag:iter: f=hclap_help;

DEBUG:clap:usage::needs_flags_tag:iter: f=vclap_version;

DEBUG:clap:usage::needs_flags_tag: [FLAGS] not required

DEBUG:clap:usage::create_help_usage: usage=bin name

DEBUG:clap:Help::write_all_args;

DEBUG:clap:Help::write_args;

DEBUG:clap:Help::write_args: Current Longest...2

DEBUG:clap:Help::write_args: New Longest...6

DEBUG:clap:Help::write_args: Current Longest...6

DEBUG:clap:Help::write_args: New Longest...9

DEBUG:clap:Help::write_arg;

DEBUG:clap:Help::short;

DEBUG:clap:Help::long;

DEBUG:clap:Help::val: arg=--help

DEBUG:clap:Help::spec_vals: a=--help

DEBUG:clap:Help::val: Has switch...Yes

DEBUG:clap:Help::val: force_next_line...false

DEBUG:clap:Help::val: nlh...false

DEBUG:clap:Help::val: taken...21

DEBUG:clap:Help::val: help_width > (width - taken)...23 > (120 - 21)

DEBUG:clap:Help::val: longest...9

DEBUG:clap:Help::val: next_line...No

DEBUG:clap:write_spaces!: num=7

DEBUG:clap:Help::help;

DEBUG:clap:Help::help: Next Line...false

DEBUG:clap:Help::help: Too long...No

DEBUG:clap:Help::write_arg;

DEBUG:clap:Help::short;

DEBUG:clap:Help::long;

DEBUG:clap:Help::val: arg=--version

DEBUG:clap:Help::spec_vals: a=--version

DEBUG:clap:Help::val: Has switch...Yes

DEBUG:clap:Help::val: force_next_line...false

DEBUG:clap:Help::val: nlh...false

DEBUG:clap:Help::val: taken...21

DEBUG:clap:Help::val: help_width > (width - taken)...26 > (120 - 21)

DEBUG:clap:Help::val: longest...9

DEBUG:clap:Help::val: next_line...No

DEBUG:clap:write_spaces!: num=4

DEBUG:clap:Help::help;

DEBUG:clap:Help::help: Next Line...false

DEBUG:clap:Help::help: Too long...No

bin-name
USAGE:

bin name
FLAGS:

-h, --help       Prints help information

-V, --version    Prints version information

[Wtoll]

I second this being a necessary addition. I'm trying to write an extension to cargo (cargo-extension binary name as an example), and in order to have the usage information make sense, the bin name has to be set to "cargo extension", but then that forces the name in the version write out to be "cargo-extension" which is not very descriptive or helpful.

Considering cargo itself uses clap I think it makes sense for clap to be fully able to support writing extensions to cargo, and part of that includes allowing the "name" field to take precedence over the "bin-name" field to allow for both an accurate usage example, and a descriptive name.

Also, because I noticed the version number in this issue is different, this also equally affects clap v3.0.0-beta.1 which is what I've been developing with.

[pksunkara]

Note: Need to check if NoBinaryName solves it.

[epage]

From a comment of mine in #3096

From help2man's docs

Use argv[0] for the program name in these synopses, just as it is, with no directory stripping. This is in contrast to the canonical (constant) name of the program which is used in --version.

Interesting. They want the usage to use argv[0] but everywhere else to the use actual name.

For us, we show the bin name as the application name (see #992). Our bin name is argv[0].file_name() though with #992 I am considering changing it to argv[0].file_stem() or similar.

[epage]

#3680 added a help_template variable for this. I'm debating whether it can be the default in 3.2 (minor compatibility break) or 4.0 (major compatibility break).

This is also helping #992

[epage]

We're close enough to when we can start working on 4.0, I'm going to play it safe and push it off to then