Uncalled function checks only works with single conditional

[mjbvz]

TypeScript Version: 3.8.0-dev.20191207

Search Terms:

Code
With strict null checks enabled:

import * as fs from 'fs';

fs.stat('/path/to/file', function(err, stats) {
    if (stats.isFile || stats.isDirectory) {

    }
});

Expected behavior:
Accesses to isFile and isDirectory are reported as errors since these are actually functions

Actual behavior:
No errors.

Errors are only reported when there is a single conditional

Playground Link:

Related Issues:

[RyanCavanaugh]

This is the intended scoping of the check to reduce over-reported errors.

[clarkio]

@RyanCavanaugh I can definitely appreciate the reduction in over-reported errors but do you think not having any error at all seems to defeat the purpose? Could there be a way to mention it once for a particular block of code?

[RyanCavanaugh]

We don't have "Just so you know" warnings and don't intend to add them

[clarkio]

I think I may be miscommunicating the scenario or misunderstanding your perspective. I'm hoping to receive the error for the one instance even if there are other conditionals.

For example here we accidentally don't call isDirectory as a function while having some other conditional with it.

import * as fs from 'fs';

fs.stat('/path/to/file', function(err, stats) {
    if (stats.isDirectory && !err) {

    }
});

At the moment if we were to do this the error around stats.isDirectory is not reported at all but if we remove the !err conditional it will report as expected.

Do you think it should still be reported in this scenario?

[DanielRosenwasser]

This is the intended scoping of the check to reduce over-reported errors.

I may have missed any checks for whether this comes up in conditionals, &&, and || - did we see too many problems on those? My hunch is that that'd be nothing but goodness.

[RyanCavanaugh]

We can try expanding the set of things checked and see what comes up.

[typescript-bot]

This issue has been marked 'Working as Intended' and has seen no recent activity. It has been automatically closed for house-keeping purposes.