lsp-test

lsp-test is a functional testing framework for Language Server Protocol servers.

import Language.Haskell.LSP.Test
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 new-test. For more examples check the Wiki

Developing

The tests are integration tests, so make sure you have the following language servers installed and on your PATH:

haskell-ide-engine

• Check out a relatively recent version of the repo, or see .travis.yml to get the exact commit used for CI.
• stack install

javascript-typescript-langserver

npm i -g javascript-typescript-langserver

Then run the tests with stack test or cabal new-test.