Enable more warnings for the ghcide codebase (#75)

Author: cocreature

azure-pipelines.yml

@@ -39,7 +39,7 @@ jobs:
         displayName: 'Install Stack'
       - bash: stack setup
         displayName: 'stack setup'
-      - bash: stack build --only-dependencies
+      - bash: stack build --only-dependencies --ghc-options=-Werror
         displayName: 'stack build --only-dependencies'
       - bash: stack test || stack test || stack test
         # ghcide stack tests are flaky, see https://github.com/digital-asset/daml/issues/2606.
@@ -83,7 +83,7 @@ jobs:
         displayName: 'Install Stack'
       - bash: stack setup --stack-yaml=stack84.yaml
         displayName: 'stack setup --stack-yaml=stack84.yaml'
-      - bash: stack build --only-dependencies --stack-yaml=stack84.yaml
+      - bash: stack build --only-dependencies --stack-yaml=stack84.yaml --ghc-options=-Werror
         displayName: 'stack build --only-dependencies --stack-yaml=stack84.yaml'
       - bash: stack test --stack-yaml=stack84.yaml || stack test --stack-yaml=stack84.yaml || stack test --stack-yaml=stack84.yaml
         # ghcide stack tests are flaky, see https://github.com/digital-asset/daml/issues/2606.
@@ -127,7 +127,7 @@ jobs:
         displayName: 'Install Stack'
       - bash: stack setup --stack-yaml=stack-ghc-lib.yaml
         displayName: 'stack setup --stack-yaml=stack-ghc-lib.yaml'
-      - bash: stack build --only-dependencies --stack-yaml=stack-ghc-lib.yaml
+      - bash: stack build --only-dependencies --stack-yaml=stack-ghc-lib.yaml --ghc-options=-Werror
         displayName: 'stack build --only-dependencies --stack-yaml=stack-ghc-lib.yaml'
       - bash: stack test --stack-yaml=stack-ghc-lib.yaml || stack test --stack-yaml=stack-ghc-lib.yaml || stack test --stack-yaml=stack-ghc-lib.yaml
         # ghcide stack tests are flaky, see https://github.com/digital-asset/daml/issues/2606.

ghcide.cabal

@@ -128,13 +128,14 @@ library
         Development.IDE.Spans.Calculate
         Development.IDE.Spans.Documentation
         Development.IDE.Spans.Type
+    ghc-options: -Wall -Wno-name-shadowing
 
 executable ghcide
     if flag(ghc-lib)
       buildable: False
     default-language:   Haskell2010
     hs-source-dirs:     exe
-    ghc-options: -threaded
+    ghc-options: -threaded -Wall -Wno-name-shadowing
     main-is: Main.hs
     build-depends:
         base == 4.*,
@@ -188,7 +189,7 @@ test-suite ghcide-tests
         text
     hs-source-dirs: test/cabal test/exe test/src
     include-dirs: include
-    ghc-options: -threaded
+    ghc-options: -threaded -Wall -Wno-name-shadowing
     main-is: Main.hs
     other-modules:
         Development.IDE.Test

src/Development/IDE/Types/Diagnostics.hs

@@ -16,7 +16,6 @@ module Development.IDE.Types.Diagnostics (
 import Data.Maybe as Maybe
 import qualified Data.Text as T
 import Data.Text.Prettyprint.Doc
-import qualified Language.Haskell.LSP.Types as LSP
 import Language.Haskell.LSP.Types as LSP (
     DiagnosticSeverity(..)
   , Diagnostic(..)

test/cabal/Development/IDE/Test/Runfiles.hs

@@ -5,8 +5,5 @@ module Development.IDE.Test.Runfiles
   ( locateGhcideExecutable
   ) where
 
-import System.FilePath (FilePath)
-
-
 locateGhcideExecutable :: IO FilePath
 locateGhcideExecutable = pure "ghcide"

test/exe/Main.hs

@@ -389,7 +389,7 @@ removeImportTests = testGroup "remove import actions"
       let contentA = T.unlines
             [ "module ModuleA where"
             ]
-      docA <- openDoc' "ModuleA.hs" "haskell" contentA
+      _docA <- openDoc' "ModuleA.hs" "haskell" contentA
       let contentB = T.unlines
             [ "{-# OPTIONS_GHC -Wunused-imports #-}"
             , "module ModuleB where"
@@ -413,7 +413,7 @@ removeImportTests = testGroup "remove import actions"
       let contentA = T.unlines
             [ "module ModuleA where"
             ]
-      docA <- openDoc' "ModuleA.hs" "haskell" contentA
+      _docA <- openDoc' "ModuleA.hs" "haskell" contentA
       let contentB = T.unlines
             [ "{-# OPTIONS_GHC -Wunused-imports #-}"
             , "module ModuleB where"