New TypeScript Operator Causes .ts Files to Not Parse

[CatGuardian]

There are a few new operators in TypeScript and one of them (maybe the other ones too) is causing the error "Unable to parse some files: ".

The operator I'm referring to is the optional chaining operator: ?.

If you have a file named 'cat.ts' and have somewhere the following code:

const x = { name: { first: 'ralph', last: 'pants' } };
console.log(`Pets name: ${x.name?.last}, ${x.name?.first}`);

then when you run gulp-depcheck you get an error: "Unable to parse some files: cat.ts"

These new TypeScript operators are like the holy grail and so this is very critical to get fixed.

---

UPDATE:

After doing some digging I discovered that this behavior is caused by the fact that gulp-depcheck has locked in an old version of depcheck itself. So in gulp-depcheck's package.json file it specifies: "depcheck": "0.6.7" But if it was updated to specify the latest version: 0.9.1, then this error doesn't come up.

WORK AROUND:

So after discovering that the issue is with an outdated version of depcheck, I noticed we can override the version of depcheck that gulp-depcheck is using.

We can do that by specifying the depcheck option when activating gulp-depcheck. See here:

var gulpDepcheck = require('gulp-depcheck');
...
gulp.task('depcheck', gulpDepcheck({
  // Override depcheck version inside gulp-depcheck.
  depcheck: require('depcheck'),

  // your other gulp-depcheck options go here still
}));

Make sure you install the version of depcheck that you want in the package that you are using gulp-depcheck: npm i depcheck --save-dev

[CatGuardian]

@mcasimir @goloroden @hh10k

To fix this issue it is really simple: you just need to update the package.json file to reference the latest depcheck version.

Please let me know your thoughts.