TurboWarp breaks any operations that depend on negitive 0 and the value not being NaN

[Tacodiva]

A simple example is ( ( 1 / 0 ) / ( -0 + -0 ) ) which returns -Infinity in TurboWarp but Infinity in Scratch

See demo project 773175910 on Scratch and TurboWarp.

This happens because ( 1 / 0 ) = Infinity and ( -0 + -0) = -0. If you double click the ( -0 + -0) block in Scratch it will report 0, but internally it is still -0, it looks like 0 because (-0).toString() is 0. ( Infinity / -0 ) = -Infinity, so Scratch handles the block correctly.

TurboWarp on the other hand turns the -0 into a 0 leaving ( Infinity / 0 ) = Infinity. This happens because TurboWarp tries to deal with the potential NaN using || 0. This operation inadvertently also converts -0 into 0, as (-0) || 0 === 0.

[GarboMuffin]

Known issue with no recorded project breakage so far

[Tacodiva]

This will be mitigated with the better type analysis, as more NaN checks will be able to be omitted.