Revert "Additional helper to get project config dir"

This reverts commit e324f19.

src/Stack/Config.hs

@@ -529,19 +529,22 @@ loadYaml path = do
     logJSONWarnings (toFilePath path) warnings
     return result
 
--- | Get the parent directory the project config file, if it exists.
-getProjectConfigDir :: (MonadIO m, MonadThrow m, MonadLogger m)
-                    => m (Maybe (Path Abs Dir))
-getProjectConfigDir = do
+-- | Get the location of the project config file, if it exists.
+getProjectConfig :: (MonadIO m, MonadThrow m, MonadLogger m)
+                 => Maybe (Path Abs File)
+                 -- ^ Override stack.yaml
+                 -> m (Maybe (Path Abs File))
+getProjectConfig (Just stackYaml) = return $ Just stackYaml
+getProjectConfig Nothing = do
     env <- liftIO getEnvironment
     case lookup "STACK_YAML" env of
         Just fp -> do
             $logInfo "Getting project config file from STACK_YAML environment"
             liftM Just $ case parseAbsFile fp of
                 Left _ -> do
                     currDir <- getWorkingDir
-                    fmap parent (resolveFile currDir fp)
-                Right path -> return (parent path)
+                    resolveFile currDir fp
+                Right path -> return path
         Nothing -> do
             currDir <- getWorkingDir
             search currDir
@@ -552,28 +555,14 @@ getProjectConfigDir = do
         $logDebug $ "Checking for project config at: " <> T.pack fp'
         exists <- fileExists fp
         if exists
-            then return $ Just dir
+            then return $ Just fp
             else do
                 let dir' = parent dir
                 if dir == dir'
                     -- fully traversed, give up
                     then return Nothing
                     else search dir'
 
--- | Get the path of the project config file, if it exists.
-getProjectConfigFile :: (MonadIO m, MonadThrow m, MonadLogger m)
-                         => Maybe (Path Abs File)
-                         -- ^ Override stack.yaml
-                         -> m (Maybe (Path Abs File))
-getProjectConfigFile (Just stackYaml) = return $ Just stackYaml
-getProjectConfigFile Nothing =
-    getProjectConfigDir >>= \case
-        Nothing ->
-            return Nothing
-        Just dir ->
-            return $
-            Just (dir </> stackDotYaml)
-
 -- | Find the project config file location, respecting environment variables
 -- and otherwise traversing parents. If no config is found, we supply a default
 -- based on current directory.
@@ -582,7 +571,7 @@ loadProjectConfig :: (MonadIO m, MonadThrow m, MonadLogger m)
                   -- ^ Override stack.yaml
                   -> m (Maybe (Project, Path Abs File, ConfigMonoid))
 loadProjectConfig mstackYaml = do
-    mfp <- getProjectConfigFile mstackYaml
+    mfp <- getProjectConfig mstackYaml
     case mfp of
         Just fp -> do
             currDir <- getWorkingDir