Flags.remove mutating to an incorrect value.

[redvers]

    t = set0011.clone()              //0b0011
    t.remove(set0101)                //0b0101
    h.assert_true(t == _TestFlagsFlags(0b0010))

The test fails as it's mutating to 0b0110.

PR incoming.

[SeanTAllen]

Do you have a reproducible example?

[SeanTAllen]

Example:

use "collections"

actor Main
  new create(env: Env) =>
    let a = _TestFlagsFlags.>set(_TestFlagA)
    let b = recover val _TestFlagsFlags.>set(_TestFlagB) end
  
    if not a(_TestFlagA) then
      env.out.print("pre Bad 1")
    end
    
    if a(_TestFlagB) then
      env.out.print("pre Bad 2")
    end
    
    if a(_TestFlagC) then
      env.out.print("pre Bad 3")
    end
    
    if a(_TestFlagD) then
      env.out.print("pre Bad 4")
    end

    a.remove(b)
    
    if not a(_TestFlagA) then
      env.out.print("Bad 1")
    end
    
    if a(_TestFlagB) then
      env.out.print("Bad 2")
    end
    
    if a(_TestFlagC) then
      env.out.print("Bad 3")
    end
    
    if a(_TestFlagD) then
      env.out.print("Bad 4")
    end

type _TestFlagsFlags is Flags[(_TestFlagA|_TestFlagB|_TestFlagC|_TestFlagD),U8]
primitive _TestFlagA fun value(): U8 => 1
primitive _TestFlagB fun value(): U8 => 2
primitive _TestFlagC fun value(): U8 => 4
primitive _TestFlagD fun value(): U8 => 8