Your environment

Which OS do you use?
Fedora
Which version of GHC do you use and how did you install it?
9.6.2 from ghcup
How is your project built (alternative: link to the project)?

Which LSP client (editor/plugin) do you use?
vim+coc.nvim
Which version of HLS do you use and how did you install it?

Have you configured HLS in any way (especially: a hie.yaml file)?
no

Steps to reproduce

Use the following file

module X where

data X a where
  X :: X Int
  Y :: X String
  Z :: X Int

a :: X Int
a = X

-- this doesn't type check on purpose:
instance Eq X where
  (==) = \_ _ -> True

Try to rename the X data type to X'.

Expected behaviour

Either nothing should be changed or everything even in presence of type errors.

Actual behaviour

module X where

data X a where
  X :: X Int
  Y :: X String
  Z :: X Int

a :: X Int
a = X

-- this doesn't type check on purpose:
instance Eq X' where
  (==) = \_ _ -> True

i.e. non of the X occurrences in the defintiion of X or a changed, only its occurrence in the Eq instance.

Debug information