Track doesn't show it's disabled with an empty stack

[phet-steele]

1. Go to http://www.colorado.edu/physics/phet/dev/html/forces-and-motion-basics/2.3.0-phetiorc.3/wrappers/state/state.html?sim=forces-and-motion-basics&relativeSimPath
2. Go to the Motion screen
3. Take all objects off the track. The track in the top sim correctly turns gray; the bottom sim's track remains white

Seen on macOS 10.12.6 Chrome. For phetsims/QA#42.

[phet-steele]

@jessegreenberg just a hunch, but it might be that only forcesAndMotionBasics.{{SCREEN}}.view.appliedForceSlider.sliderKnob.enabledProperty is instrumented, but not also the track.enabledProperty (or equivalent).

[jessegreenberg]

@phet-steele yes, I think you are right. It looks like both enabledProperty in sun/HSliderTrack and sun/HSlider is not instrumented. The enabledProperty is shared between both (passed through options).

Temporary solution is to pass an instrumented enabledProperty to HSlider in AppliedForceSlider.

[jessegreenberg]

That fixes it, but I am wondering if this should be handled in Sun?

[jessegreenberg]

Being investigated in https://github.com/phetsims/sun/issues/310, on hold until we investigate that issue.

[jessegreenberg]

https://github.com/phetsims/sun/issues/310 was closed, this issue should be fixed.

[jessegreenberg]

Verified fixed in master, removed custom code in AppliedForceSlider.

[jessegreenberg]

2.3-phetio and 2.3 have sun sha 50f640e713ff6c764ec1484fb546370c18abe1ad.

To pick up this fix they need changes through 96c223b3fb271992069088e4d48019b141c9191c

[jessegreenberg]

Changes between those SHA's seem either related to this issue, are adding documentation, or were for sorting require statements, so it seems safe to update the shas in dependencies.json without creating release branches in sun.

[jessegreenberg]

Both also require an updated DOT sha to include TRange db33a2c7fca14980bccd7d9517839c5b8ae7a9ee

[jessegreenberg]

Should be fixed in release branches.

[phet-steele]

Beautiful, fixed.