Bad error message for a misaligned case block in a do-let expression

Consider the following code:

main = do
  code <- getCode
  let value = case code of
     1 -> 2
     3 -> 4
     _ -> 5
  print value

This is a parse error, as the indent of the case statements is under the indent introduced by let. However, the error message on 8.6 onwards is very misleading:

/home/dkr/example/Bad.hs:2:8: error:
    Unexpected do block in function application:
        do code <- getCode
           let value = ...
    You could write it with parentheses
    Or perhaps you meant to enable BlockArguments?
  |
2 | main = do
  |        ^^...

Compare this with 8.4, which is a bit less bad:

/home/dkr/example/Bad.hs:5:6: error: parse error on input ‘1’
  |
5 |      1 -> 2
  |      ^

Trac metadata

Trac field	Value
Version	8.6.2
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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