Typed holes inferring a more polymorphic type

Consider these two snippets.

testFailure :: Char
testFailure =
  let x = id _
  in  x

Suggestions provided were

/home/sreenidhi/Experiments/TypedHole.hs:3:14: error:
    • Found hole: _ :: a
      Where: ‘a’ is a rigid type variable bound by
               the inferred type of x :: a
               at /home/sreenidhi/Experiments/TypedHole.hs:3:7-14
    • In the first argument of ‘id’, namely ‘_’
      In the expression: id _
      In an equation for ‘x’: x = id _
    • Relevant bindings include
        x :: a (bound at /home/sreenidhi/Experiments/TypedHole.hs:3:7)
        testFailure :: Char
          (bound at /home/sreenidhi/Experiments/TypedHole.hs:2:1)

whereas for this one

testSuccess :: Char
testSuccess = _

It correctly suggests

/home/sreenidhi/Experiments/TypedHole.hs:7:15: error:
    • Found hole: _ :: Char
    • In the expression: _
      In an equation for ‘testSuccess’: testSuccess = _
    • Relevant bindings include
        testSuccess :: Char
          (bound at /home/sreenidhi/Experiments/TypedHole.hs:7:1)
      Valid hole fits include
        testSuccess :: Char
          (bound at /home/sreenidhi/Experiments/TypedHole.hs:7:1)
        testFailure :: Char
          (defined at /home/sreenidhi/Experiments/TypedHole.hs:2:1)
        maxBound :: forall a. Bounded a => a
          with maxBound @Char
          (imported from ‘Prelude’ at /home/sreenidhi/Experiments/TypedHole.hs:1:1
           (and originally defined in ‘GHC.Enum’))
        minBound :: forall a. Bounded a => a
          with minBound @Char
          (imported from ‘Prelude’ at /home/sreenidhi/Experiments/TypedHole.hs:1:1
           (and originally defined in ‘GHC.Enum’))

Trac metadata

Trac field	Value
Version	8.6.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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