better error reporting for cradle failure (`stack setup --silent` case)

[alanz]

I don't have stack set up on my machine, did a clean checkout of this repo, configured and built with cabal, and when I try to open ../ghcide/test/src/Development/IDE/Test.hs I get told the language server exited, and the following shows up in the *lsp-haskell::stderr* buffer.

Current directory: /Users/alanzimm/repos/haskell/haskell-language-server
Operating system: darwin
Arguments: ["--lsp","-d","-l","/var/folders/vy/nf8sc07944324wf17pg48m2r0000gn/T/hls.log"]
Cradle directory: /Users/alanzimm/repos/haskell/haskell-language-server
Cradle type: Stack

Tool versions found on the $PATH
cabal:		3.2.0.0
stack:		2.1.3
ghc:		8.10.3


Consulting the cradle to get project GHC version...
Failed to get project GHC version:CradleError {cradleErrorDependencies = [], cradleErrorExitCode = ExitFailure 1, cradleErrorStderr = ["Error when calling stack exec --silent ghc -- --numeric-version","",""]}

Process lsp-haskell stderr<3> finished

Your environment

Output of haskell-language-server --probe-tools or haskell-language-server-wrapper --probe-tools:

haskell-language-server --probe-tools
haskell-language-server version: 0.5.1.0 (GHC: 8.10.2) (PATH: /Users/alanzimm/.cabal/store/ghc-8.10.2/hskll-lngg-srvr-0.5.1.0-9b087dc4/bin/haskell-language-server)
Tool versions found on the $PATH
cabal:		3.2.0.0
stack:		2.1.3
ghc:		8.10.3

Which lsp-client do you use: emacs lsp-mode

Describe your project (alternative: link to the project):

Contents of hie.yaml: none

Steps to reproduce

Make a clean checkout of this repo at f03a7fa, build it, and open the designated file

Expected behaviour

It should start up properly

Actual behaviour

I get Server lsp-haskell:793 status:starting exited with status exit. Do you want to restart it? (y or n), and the log at the top

[jneira]

There is an old issue from ghcide asking for a better error reporting when failing builds through hie-bios: #710
In that case the server (ghcide) did not crash afaiu.

[fendor]

I opened haskell/hie-bios#254 to improve this, but we didn't verify yet that it has no unintended side-effects

[jneira]

I see lot of reports of this: hls failing to load the project with stack setup --silent with no clue in the log about the concrete error.
The rutinary advise is tell users run the command directly to access the log.

[fendor]

We should probably capture the output from stack setup and write everything into CradleError.

[jneira]

We should probably capture the output from stack setup and write everything into CradleError.

But the ghc setup (downloading and installing) would make it lot lot longer 🤔

[fendor]

True, but otherwise it is rather hard to debug, and we should ideally not require users to look into the logs to understand what went wrong.

[jneira]

And what about make two calls one silent and other one with output? or only populate/show the log in CradleError if the command exits with error?

[fendor]

The latter is what I had in mind, we only want to show the logs if some error is thrown