fix: support CLIs with single top level command

[mdonnalley]

Support CLIs with a single top level command (i.e. the executable is the only command).

With this fix, users will need to do two things:

1. Place their command at the top level of the commands dir, e.g. src/commands/index.ts
2. Supply the default in their oclif config, for example

oclif: {
  default: ".",
  commands: "./dist/commands"
}

Fixes #425

[felipecrs]

Please let me know if the below migration would be correct then:

1. Add to package.json:

{
  "oclif": {
    "default": ".",
    "commands": "./lib" // as my "index.ts" is at "src/index.ts" and my tsc builds to "lib"
  }
}

[mdonnalley]

Please let me know if the below migration would be correct then:

1. Add to package.json:

{
  "oclif": {
    "default": ".",
    "commands": "./lib" // as my "index.ts" is at "src/index.ts" and my tsc builds to "lib"
  }
}

That should also work

[felipecrs]

It works, but the --help now displays two sections (while it should only display the first):

❯ bin/dev --help
Downloads and extracts binaries from compressed packages using a config file

USAGE
  $ bindl . [--version] [--help] [-c <value>]

FLAGS
  -c, --config=<value>  Path to the config file
  --help                Show CLI help.
  --version             Show CLI version.

DESCRIPTION
  Downloads and extracts binaries from compressed packages using a config file

  The config will be read from any valid config file in the current directory. The configuration file can be defined
  using all the extensions and names accepted by cosmiconfig, such as bindl.config.js



Downloads and extracts binaries from compressed packages using a config file

VERSION
  bindl/2.0.0 wsl-x64 node-v16.15.1

USAGE
  $ bindl [COMMAND]

COMMANDS
  .  Downloads and extracts binaries from compressed packages using a config file

[felipecrs]

Another issue:

• bindl . triggers the main command (while it should actually pass . as argument to the main command).

[mdonnalley]

@felipecrs I pushed a commit last night that should resolve the issues you're seeing - let me know if that works better for you

[felipecrs]

@mdonnalley thank you! I will test and let you know.