TS2531: Object is possibly 'null' but it is certain not null. switch(true) pattern.

[Artuar]

I tried to use switch(true) pattern in my code and found a bug.
There is a similar piece of code that shows the same bug.
Try it on the playground.

Playground Link:
TS Playground

Code

const switchTruePattern = (value1: number | null, value2: number | null) => {
    switch (true) {
        case value1 !== null && value2 !== null:
            return value1 + value2;
        case value1 !== null:
            return value1;
        default:
            return value2;
    }
};

TypeScript Version: 4.0.2

Expected behavior:
TS should correctly assume that next cannot be null after the conditional statement.

Actual behavior:
It throws TS2531: Object is possibly 'null'.

Related Issues:
#35964

[MartinJohns]

Essentially a duplicate of #37178. Just the details vary slightly.

[RyanCavanaugh]

Please search a bit more diligently before logging new issues. Thanks!