Import/export errors block import/export re-scanning

[deemp]

Your environment

Which OS do you use:
Ubuntu 20.04
Which LSP client (editor/plugin) do you use:
VS Code+Haskell+enabled autosave there
Describe your project (alternative: link to the project):
link

Steps to reproduce

1. Clone the project's repo and switch to the second commit (link). In module A, module B will be highlighted red.
   
2. Create B.hs as in the third commit (link). Though B does export b, in module A, module B will still be highlighted red.
   
   And there will be an error
   

Expected behaviour

When a module exports a function, the errors for modules which expected such function should be re-checked.

Actual behaviour

Instead, if there happens an error, HLS blocks further export/import checks, and there is no way to make checks start again without restarting the HLS

Include debug information

[pepeiborra]

This looks like a regression.
What version of HLS are you using?
Did this use to work with previous versions of HLS?

[deemp]

Doesn't work on both 1.7.0.0 and 1.6.1.0. Manage them with ghcup

[deemp]

@pepeiborra, I have a similar issue in another, slightly more complicated package A with a module F. I cloned a package B with modules C and D there, made hie.yaml, etc. In this package B, module D re-exports the contents of module C. When I try to import a not-yet-exported function from D into F, I get an error like " D doesn't export such function". Then, I add a necessary export into C, then import and export in D, but HLS still doesn't recognize these imports in F until I restart it.

Here's the project.

• F is src/EO/EOtoPhi.hs
• D is eo-parser/src/EOParser.hs
• C is eo-parser/src/ToTerm.hs

[michaelpj]

I've definitely observed HLS invalidating things properly when I change a cabal file. I wonder if it's a problem with stack cradles?

[michaelpj]

I haven't seen anything like this recently, is this still a problem?