Execution ordering in tuples and assignments is off

[plotchy]

pragma solidity >=0.8.0;
contract struct_push {

    mapping(uint => uint) map;
    uint public index;
    uint public a;

    function foo() public payable returns (uint, uint, uint, uint, uint) {
        require(index == 0);
        (a, map[++index]) = (index, bar(++index));
        
        return (a, index, map[0], map[1], map[2]);
    }

    function bar(uint i) internal pure returns (uint) {
        return i;
    }
}

Foundry output of foo():

Running 1 test for test/any.t.sol:CounterTest
[PASS] testPush() (gas: 54875)
Traces:
  [172906] CounterTest::setUp() 
    ├─ [118365] → new struct_push@0x5615dEB798BB3E4dFa0139dFa1b3D433Cc23b72f
    │   └─ ← 591 bytes of code
    └─ ← ()

  [54875] CounterTest::testPush() 
    ├─ [49591] struct_push::foo() 
    │   └─ ← 0, 2, 0, 0, 1
    └─ ← ()

Test result: ok. 1 passed; 0 failed; finished in 248.38µs

Pyrometer output of foo():

a == 1, though is expected to be 0.
map[2] == [0, 2^256-1] and is expected to be 1. Though all the mapping slots are pessimistic so this seems currently unsupported.