From ec2a139c9281f8274eb9ecfa66d06ba7f7679831 Mon Sep 17 00:00:00 2001
From: Michael Sloan <mgsloan@gmail.com>
Date: Thu, 24 Jan 2019 20:42:10 -0800
Subject: [PATCH] Have "stack script" set import search path #3377

---
 ChangeLog.md        |  6 ++++++
 src/Stack/Script.hs | 11 ++++++-----
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/ChangeLog.md b/ChangeLog.md
index df1a21bbff..9db22e36f6 100644
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -46,6 +46,12 @@ Major changes:
 Behavior changes:
 * `stack.yaml` now supports `snapshot`: a synonym for `resolver`. See [#4256](https://github.com/commercialhaskell/stack/issues/4256)
 
+* `stack script` now passes `-i -idir` in to the `ghc`
+  invocation. This makes it so that the script can import local
+  modules, and fixes an issue where `.hs` files in the current
+  directory could affect interpretation of the script. See
+  [#4538](https://github.com/commercialhaskell/stack/pull/4538)
+
 Other enhancements:
 
 * Defer loading up of files for local packages. This allows us to get
diff --git a/src/Stack/Script.hs b/src/Stack/Script.hs
index a733381971..568e4e00ff 100644
--- a/src/Stack/Script.hs
+++ b/src/Stack/Script.hs
@@ -35,11 +35,12 @@ import qualified RIO.Text as T
 scriptCmd :: ScriptOpts -> GlobalOpts -> IO ()
 scriptCmd opts go' = do
     file <- resolveFile' $ soFile opts
-    let go = go'
+    let scriptDir = parent file
+        go = go'
             { globalConfigMonoid = (globalConfigMonoid go')
                 { configMonoidInstallGHC = First $ Just True
                 }
-            , globalStackYaml = SYLNoConfig $ parent file
+            , globalStackYaml = SYLNoConfig scriptDir
             }
     withDefaultBuildConfigAndLock go $ \lk -> do
       -- Some warnings in case the user somehow tries to set a
@@ -92,7 +93,8 @@ scriptCmd opts go' = do
                     withNewLocalBuildTargets targets $ Stack.Build.build Nothing lk
 
         let ghcArgs = concat
-                [ ["-hide-all-packages"]
+                [ ["-i", "-i" ++ toFilePath scriptDir]
+                , ["-hide-all-packages"]
                 , maybeToList colorFlag
                 , map (\x -> "-package" ++ x)
                     $ Set.toList
@@ -109,13 +111,12 @@ scriptCmd opts go' = do
           SEInterpret -> exec ("run" ++ compilerExeName wc)
                 (ghcArgs ++ toFilePath file : soArgs opts)
           _ -> do
-            let dir = parent file
             -- Use readProcessStdout_ so that (1) if GHC does send any output
             -- to stdout, we capture it and stop it from being sent to our
             -- stdout, which could break scripts, and (2) if there's an
             -- exception, the standard output we did capture will be reported
             -- to the user.
-            withWorkingDir (toFilePath dir) $ proc
+            withWorkingDir (toFilePath scriptDir) $ proc
               (compilerExeName wc)
               (ghcArgs ++ [toFilePath file])
               (void . readProcessStdout_)