Type inference in switches over expressions pointing to nested properties does not work

[u840903]

TypeScript Version: 4.1.2, 4.2.0-dev.20201205

Search Terms: type inference switch statement

Code

enum TYPES {
    ONE = 'one',
    TWO = 'two'
}

interface IOne {
    a: string,
     type: TYPES.ONE
     meta: {
         type: TYPES.ONE
     }
}

interface ITwo {
    b: string,
    type: TYPES.TWO
    meta : {
        type: TYPES.TWO
    }
}

[].map((block:IOne | ITwo) => {
    // This works.
    switch (block.type) {
        case TYPES.ONE:
            block.a 
            break;
        case TYPES.TWO:
            block.b 
            break;
    }

    // This does NOT work.
    switch (block.meta.type) {
        case TYPES.ONE:
            block.a 
            break;
        case TYPES.TWO:
            block.b 
            break;
    }
});

Expected behavior:
The switch over block.meta.type should infer the same types as the switch over block.type.

Actual behavior:
The swich over block.meta.type errors the following and does not infer type correctly. The switch over block.type DOES infer type correctly.

Property 'a' does not exist on type 'IOne | ITwo'. Property 'a' does not exist on type 'ITwo'.
Property 'b' does not exist on type 'IOne | ITwo'. Property 'b' does not exist on type 'IOne'.

Playground Link:
https://www.typescriptlang.org/play?ts=4.1.2#code/KYOwrgtgBAKgmgBQKIGUoG8BQUdQPIBySUAvFAOQD2Iw5ANNrjAOp6kUAuA7peZgL6ZMASxAdgAJwBmAQwDGwKAEk8NDIxwyAXFADOHCaIDmDXDg4BPAA7Ad8ZCgB0hJBpwRgHberO-LNu0RUZyI3KEFBETFJWQVlGB4fXAAjHX1DEBM3f1tYIKcWPDcPLygdLF9cHMCHR0K3CKEAbQBdRwgZKwAKLuSAG0o5AGstFTUAH3ieAEpSAD4knAB6JdgAC2FdKB4JId1HN10uYQ45NahegeHHHNmKyqg5GV1Fe2CXLTCH-sGhxxkoF9KskJMAZEMANxAx7PV75OqsT4PXw-a7JQHIswgsGQhpCMwrdabKAAE0owC2BDwMG2lF2BzMRxOZwuqL+JRkN2swDu0KeLzytQ+0KxVz+AJFKVB4KhyP5cNqhSRmJwbMc6MlquluLMEWmEKAA

Related Issues:
#30763
#30557
#30593

Note:
I'm sorry if this is obvious or at least an obvious duplicate. I've searched, I've asked on Gitter and Stack Overflow. I'm fairly new to Typescript and this is my first bug repport. I did my best.

[RyanCavanaugh]

Duplicate #18758

[u840903]

Possible workaround using a combination of type guards and generics can be found here. https://stackoverflow.com/questions/65139900/when-does-typescript-type-inference-in-switch-statements-work