Tiny: Add InExpression argument check

[roji]

Just to tighten things up, it's currently possible to construct in invalid InExpression via Update.

[smitpatel]

I am not sure we need to add this validation as it is all provider code and highly unlikely to end up with both non-null unless typo or intentionally badly written code.

[roji]

I am not sure we need to add this validation as it is all provider code and highly unlikely to end up with both non-null unless typo or intentionally badly written code.

I agree it's highly unlikely, it's just a validation check which also documents the invariant of this class. Is there any downside?

[smitpatel]

Downside is maintenance. We have a lot of invariant in query pipeline, we don't have validation checks which throws exception for every one of them. We could add those but cost of maintaining them/updating them if anything changes is high compared value it provides.

[roji]

I'm not saying we should start a systematic search of all unexpressed invariants or anything. This is just something I came across which doesn't cost anything to do and improves correctness/readability a bit. We can do these opportunistically as we come across them (like I did here). I don't think this single correctness check adds any burden of maintenance.

[smitpatel]

Blocked on #19233

[roji]

@smitpatel moved the check from the constructor to Update as requested.