[Bug Report] Adding sourceRectAtTime() Expression Crashes AE

[Ethan5EC1]

When attempting to add a sourceRectAtTime() expression to a Mask Path property that references a text layer, After Effects will immediately crash upon evaluation.

Reproduction steps:
1. Create a new project
2. Create a new composition (tested with HDTV 1080 29.97 preset for repro purposes)
3. Add a text layer
4. Create a comp-size solid
5. Add a comp-size mask to the solid by double clicking the mask button
6. On the "Mask Path" property of the mask created in step 5, add the expression: `thisComp.layer().sourceRectAtTime()

After clicking out of the expression editor and allowing AE to evaluate, After Effects crashes.

OS: Windows 10 Pro
OS Build: 19041.572
AE Version: 18.0.1 (Build 1)

[Bruno Quintin]

Indeed it crashes if you put a "sourceRecAtTime()" expression to a Mask Path property.
It should return an error.
Here is an expression to create a rectangular mask on a solid based on the size of another layer :

var targetedLayer = thisComp.layer();
var W = targetedLayer.sourceRectAtTime().width;
var H = targetedLayer.sourceRectAtTime().height;
var X = targetedLayer.sourceRectAtTime().left;
var Y = targetedLayer.sourceRectAtTime().top;
var point1 = targetedLayer.toComp([X,Y]);
var point2 = targetedLayer.toComp([X+W,Y]);
var point3 = targetedLayer.toComp([X+W,Y+H]);
var point4 = targetedLayer.toComp([X,Y+H]);
createPath(points = [point1,point2,point3,point4], inTangents = [], outTangents = [], is_closed = true)

[Ethan5EC1]

Thanks, Bruno.
And to clarify my original post for the devs, I expect this expression as written to return an error - not that it should work - instead of crashing.

[JohnColombo]

Hi Ethan,

Thank you for reporting this issue! We are able to reproduce this crash as well. Our team is now tracking it internally and we will investigate the root cause for a fix in a future version of AE.

Thanks again,
- John, After Effects Engineering Team