&& and || expression will not change the NONNULL flag

[HerrCai0907]

This code should not pass the compile.

export function _start(): void {
  let value: A | null = new A();
  if (value != null) {
    // value = null;  // cause compile error correctly
    true && (value = null); // compile passed, but value is changed to zero now
    let a1 = value.a1;
  }
}

[dcodeIO]

Looking at this briefly, the cause here seems to be in the && respectively || cases in Compiler#compileBinaryExpression, where the state of rightFlow is not inherited by the parent flow, so its mutations are lost.

[dcodeIO]

This issue will be addressed as part of #2578 (not yet merged) alongside a broader refactoring of the relevant flow logic solving similar issues in other places.