Prevent duplicate missing module diagnostics

Author: pepeiborra

Diff for: ghcide/src/Development/IDE/Core/Rules.hs

@@ -691,27 +691,31 @@ loadGhcSession = do
 
     defineNoDiagnostics $ \GhcSessionDeps file -> do
         env <- use_ GhcSession file
-        Just <$> ghcSessionDepsDefinition False env file
+        ghcSessionDepsDefinition False env file
 
-ghcSessionDepsDefinition :: Bool -> HscEnvEq -> NormalizedFilePath -> Action HscEnvEq
+ghcSessionDepsDefinition :: Bool -> HscEnvEq -> NormalizedFilePath -> Action (Maybe HscEnvEq)
 ghcSessionDepsDefinition forceLinkable env file = do
     let hsc = hscEnv env
-    deps <- mapMaybe (fmap artifactFilePath . snd) <$> use_ GetLocatedImports file
-    _ <- uses_ ReportImportCycles deps
-    ms:mss <- map msrModSummary <$> uses_ GetModSummaryWithoutTimestamps (file:deps)
-
-    depSessions <- map hscEnv <$> uses_ GhcSessionDeps deps
-    let uses_th_qq =
-            xopt LangExt.TemplateHaskell dflags || xopt LangExt.QuasiQuotes dflags
-        dflags = ms_hspp_opts ms
-    ifaces <- if uses_th_qq || forceLinkable
-                then uses_ GetModIface deps
-                else uses_ GetModIfaceWithoutLinkable deps
-
-    let inLoadOrder = map hirHomeMod ifaces
-    session' <- liftIO $ mergeEnvs hsc mss inLoadOrder depSessions
-
-    liftIO $ newHscEnvEqWithImportPaths (envImportPaths env) session' []
+
+    mbdeps <- mapM(fmap artifactFilePath . snd) <$> use_ GetLocatedImports file
+    case mbdeps of
+        Nothing -> return Nothing
+        Just deps -> do
+            _ <- uses_ ReportImportCycles deps
+            ms:mss <- map msrModSummary <$> uses_ GetModSummaryWithoutTimestamps (file:deps)
+
+            depSessions <- map hscEnv <$> uses_ GhcSessionDeps deps
+            let uses_th_qq =
+                    xopt LangExt.TemplateHaskell dflags || xopt LangExt.QuasiQuotes dflags
+                dflags = ms_hspp_opts ms
+            ifaces <- if uses_th_qq || forceLinkable
+                        then uses_ GetModIface deps
+                        else uses_ GetModIfaceWithoutLinkable deps
+
+            let inLoadOrder = map hirHomeMod ifaces
+            session' <- liftIO $ mergeEnvs hsc mss inLoadOrder depSessions
+
+            Just <$> liftIO (newHscEnvEqWithImportPaths (envImportPaths env) session' [])
 
 -- | Load a iface from disk, or generate it if there isn't one or it is out of date
 -- This rule also ensures that the `.hie` and `.o` (if needed) files are written out.

Diff for: plugins/hls-eval-plugin/src/Ide/Plugin/Eval/CodeLens.hs

@@ -27,7 +27,7 @@ module Ide.Plugin.Eval.CodeLens (
 
 import           Control.Applicative             (Alternative ((<|>)))
 import           Control.Arrow                   (second, (>>>))
-import           Control.Exception               (assert, try)
+import           Control.Exception               (try)
 import qualified Control.Exception               as E
 import           Control.Lens                    (_1, _3, (%~), (<&>), (^.))
 import           Control.Monad                   (guard, join, void, when)
@@ -38,31 +38,23 @@ import           Data.Char                       (isSpace)
 import qualified Data.HashMap.Strict             as HashMap
 import           Data.List                       (dropWhileEnd, find,
                                                   intercalate, intersperse)
-import           Data.Maybe                      (catMaybes, fromMaybe, isJust)
+import           Data.Maybe                      (catMaybes, fromMaybe)
 import           Data.String                     (IsString)
 import           Data.Text                       (Text)
 import qualified Data.Text                       as T
 import           Data.Time                       (getCurrentTime)
 import           Data.Typeable                   (Typeable)
-import           Development.IDE                 (Action, GetDependencies (..),
-                                                  GetModIface (..),
-                                                  GetModSummary (..),
-                                                  GhcSessionIO (..),
-                                                  HiFileResult (hirHomeMod, hirModSummary),
-                                                  HscEnvEq, IdeState,
+import           Development.IDE                 (GetModSummary (..),
+                                                  GhcSessionIO (..), IdeState,
                                                   ModSummaryResult (..),
                                                   NeedsCompilation (NeedsCompilation),
                                                   evalGhcEnv, hscEnv,
-                                                  hscEnvWithImportPaths,
                                                   prettyPrint, runAction,
                                                   textToStringBuffer,
                                                   toNormalizedFilePath',
                                                   uriToFilePath', useNoFile_,
-                                                  useWithStale_, use_, uses_)
-import           Development.IDE.Core.Compile    (loadModulesHome,
-                                                  setupFinderCache)
-import           Development.IDE.Core.Rules      (TransitiveDependencies (transitiveModuleDeps),
-                                                  ghcSessionDepsDefinition)
+                                                  useWithStale_, use_)
+import           Development.IDE.Core.Rules      (ghcSessionDepsDefinition)
 import           Development.IDE.GHC.Compat      hiding (typeKind, unitState)
 import qualified Development.IDE.GHC.Compat      as Compat
 import qualified Development.IDE.GHC.Compat      as SrcLoc
@@ -544,7 +536,8 @@ runGetSession st nfp = liftIO $ runAction "eval" st $ do
     let fp = fromNormalizedFilePath nfp
     ((_, res),_) <- liftIO $ loadSessionFun fp
     let env = fromMaybe (error $ "Unknown file: " <> fp) res
-    hscEnv <$> ghcSessionDepsDefinition False env nfp
+    res <- fmap hscEnv <$> ghcSessionDepsDefinition False env nfp
+    return $ fromMaybe (error $ "Unable to load file: " <> fp) res
 
 needsQuickCheck :: [(Section, Test)] -> Bool
 needsQuickCheck = any (isProperty . snd)