TypeScript Version:

nightly (1.9.0-dev.20160604-1.0)

Code

let foo:number|null = 0;

switch(foo) {
  case null:
    break;
  case 0:
    console.log('bar');
}

Expected behavior:
Null check should be allowed

Actual behavior:
Compiler complains "TypeScript Type 'null' is not comparable to type 'number'. (TS2678)"

Note:
If I add an 'if' condition before the switch, the compiler does not complain about either the 'if' or the switch. For instance:

let foo:number|null = 0;

if (foo === null) { console.log('bar'); }

switch(foo) {
  case null:
    break;
  case 0:
    console.log('bar');
}