lsp-test
lsp-test is a functional testing framework for Language Server Protocol servers.
It is part of the lsp family of
packages, along with lsp
and lsp-types
import Language.LSP.Test
main = runSession "hie" fullCaps "proj/dir" $ do
doc <- openDoc "Foo.hs" "haskell"
skipMany anyNotification
symbols <- getDocumentSymbols doc
Examples
Unit tests with HSpec
describe "diagnostics" $
it "report errors" $ runSession "hie" fullCaps "test/data" $ do
openDoc "Error.hs" "haskell"
[diag] <- waitForDiagnosticsSource "ghcmod"
liftIO $ do
diag ^. severity `shouldBe` Just DsError
diag ^. source `shouldBe` Just "ghcmod"
Replaying captured session
replaySession "hie" "test/data/renamePass"
Parsing with combinators
skipManyTill loggingNotification publishDiagnosticsNotification
count 4 (message :: Session ApplyWorkspaceEditRequest)
anyRequest <|> anyResponse
Try out the example tests in the example directory with cabal test.
For more examples see this introductory blog post.
Whilst writing your tests you may want to debug them to see what’s going wrong.
You can set the logMessages and logStdErr options in SessionConfig to see what the server is up to.
There are also corresponding environment variables so you can turn them on from the command line:
LSP_TEST_LOG_MESSAGES=1 LSP_TEST_LOG_STDERR=1 cabal test
Developing
The tests for lsp-test use a dummy server found in test/dummy-server/.
Run the tests with cabal test or stack test.
Tip: If you want to filter the tests, use cabal run test:tests -- -m "foo"
Troubleshooting
Seeing funny stuff when running lsp-test via stack? If your server is built upon Haskell tooling, keep in mind that stack sets some environment variables related to GHC, and you may want to unset them.
