Strip CRs in import lines

Author: snoyberg

ChangeLog.md

@@ -76,6 +76,8 @@ Bug fixes:
 * `stack upload` no longer reveals your password when you type it on
   MinTTY-based Windows shells, such as Cygwin and MSYS2.
   See [#3142](https://github.com/commercialhaskell/stack/issues/3142)
+* `stack script`'s import parser will now properly parse files that
+  have Windows-style line endings (CRLF)
 
 
 ## 1.4.0

src/Stack/Script.hs

@@ -266,8 +266,15 @@ loadModuleInfo name = do
 
 parseImports :: ByteString -> (Set PackageName, Set ModuleName)
 parseImports =
-    fold . mapMaybe parseLine . S8.lines
+    fold . mapMaybe (parseLine . stripCR) . S8.lines
   where
+    -- Remove any carriage return character present at the end, to
+    -- support Windows-style line endings (CRLF)
+    stripCR bs
+      | S8.null bs = bs
+      | S8.last bs == '\r' = S8.init bs
+      | otherwise = bs
+
     stripPrefix x y
       | x `S8.isPrefixOf` y = Just $ S8.drop (S8.length x) y
       | otherwise = Nothing