Error in the check for option name clash function in 6.0.0

[jceloi]

It seems to me that there is a bug in the new name clash feature. I do have a clash where there should be no.
I've added some logs to get inputs :

_checkForOptionNameClash :
Option : {"flags":"--opts ","required":true,"optional":false,"variadic":false,"mandatory":false,"long":"--opts","negate":false,"description":"specify opts path"}

Current this.options does not contain '--no-opts' -> this._findOption(negativeLongFlag) returns 'undefined'
!undefined -> foundClash = true -> throws 'Error: option 'opts' clashes with existing property 'opts' on Command'

So there is a clash whereas neither the positive no the negative option does exist.
Am I missing something ? It seems to be problematic to me.

[shadowspawn]

The Command object has a method called .opts() which is what your --opts is clashing with.

const { program } = require('commander');
program.storeOptionsAsProperties(true); // To suppress new exception and demonstrate problem

program
  .option('--opts <value>');
program.parse();

console.log(program.opts);
console.log(program.opts());

$ node index.js 
[Function: opts]
{ opts: [Function: opts] }

$ node index.js --opts value
value
/Users/john/Documents/Sandpits/commander/issues/1308/index.js:9
console.log(program.opts());
                    ^

TypeError: program.opts is not a function
... stack

[jceloi]

Hello @shadowspawn , thanks for the answer, I do get now why I had something not undefined here line 451 and I got confused on the code's intent on line 464.

Just to get with a little more context : the module using Commander and providing it with an 'opts' parameter is mocha-isolation https://www.npmjs.com/package/mocha-isolation

[shadowspawn]

Interesting. The deprecated mocha-isolation is likely to break! It is using any version of Commander:

  "dependencies": {
    "colors": "*",
    "commander": "*",
    "mocha": "*"
  },

And in addition is using the global Command, so won't play well with other parts of program using Commander:

const program = require('commander');

[shadowspawn]

The new clash error is going to get hit when people upgrade with existing clashes that they didn't know about or worked around. We can try and improve the message if other people are confused too.

[shadowspawn]

An answer was provided, and it hasn't come up again in a month. Closing as resolved.

Feel free to open a new issue if it comes up again, with new information and renewed interest.