#903 explains the test issue, which appears as

  Unit
    constructor
      ✓ should create square meter correctly
    toNumeric
      1) should simplify units before returning a numeric value


  1 passing (33ms)
  1 failing

  1) Unit toNumeric should simplify units before returning a numeric value:

      AssertionError [ERR_ASSERTION]: 1e-8 deepEqual 0.01
      + expected - actual

      -1e-8
      +0.01
      
      at Context.<anonymous> (test/type/unit/Unit.test.js:259:14)

Thanks @AlexanderBeyn for this fix ! And sorry for the late reply - I'm just back from holidays.

One question: shouldn't this.simplifyUnitListLazy() be called on top of the toNumeric() method instead of halfway? Or call other.simplifyUnitListLazy() instead of this.simplifyUnitListLazy()? Since we're dealing with other only in this method, and other can be replace in the first
if (valuelessUnit) {...} statement.

You're absolutely right. I've updated the pull request to use other instead of this.

Thanks for updating.

The code looks ok, though the unit test that you've added for this specific use case is failing, can you check that out?

I've changed to use mass squared instead of length squared for the units, but this test still feels brittle because of the issue described in #903.

Thanks for the fix. The non-deterministic behavior of units indeed make unit tests a bit fragile :(