feat(assert): type narrowing for assertLess, assertLessOrEqual, asserGreater, assertGreaterOrEqual

[dandv]

• disallow undefined actual values because any comparison with undefined returns false
• disallow null expected values
• narrow the returned type to exclude undefined
• drive-by typo fix and relative path imports

Fixes #6244.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.49%. Comparing base (cc9a7c0) to head (80d9af5).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #6245   +/-   ##
=======================================
  Coverage   96.49%   96.49%           
=======================================
  Files         536      536           
  Lines       41179    41189   +10     
  Branches     6175     6178    +3     
=======================================
+ Hits        39735    39745   +10     
- Misses       1401     1402    +1     
+ Partials       43       42    -1     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[dandv]

On a second thought (after my #6244 issue), assertLess & friends should not accept undefined, because any comparison with undefined returns false.

If x can be undefined, any comparison with x, e.g. assert(x < 1), produces a Deno error that x is possibly undefined:

const x = Math.random() > 1.0 ? 10 : undefined;

console.log(x < 3);  // error: TS18048 [ERROR]: 'x' is possibly 'undefined'.

So I've added typing for these assertions to also expect actual to be any type except undefined.

actual: Exclude<T, undefined> | null,

The error isn't pretty, but it's better than nothing:

Argument of type 10 | undefined is not assignable to parameter of type 0 | 10 | null
Type undefined is not assignable to type 0 | 10 | null

The | null is there for explicitness, because comparison with null are valid (null gets coerced to zero). Removing it leads to slightly simpler errors:

Argument of type 10 | undefined is not assignable to parameter of type 0 | 10
Type undefined is not assignable to type 0 | 10

[kt3k]

This relative import doesn't work when published to JSR as each package is published independently

[dandv]

I made that change because the @std import led to this error when using the repo with file:/// imports from 3rd party code:

Relative import path "@std/internal/build-message" not prefixed with / or ./ or ../ and not in import map

Is there a syntax that would work in both cases, or should I revert the change from the first commit of this PR?

[dandv]

I guess an import map in the 3rd party code would solve the problem. Feel free to cherry-pick / ignore the first commit.