Make ForeignPtr and Ptr coexist

Author: vkleen

src/Language/Rust/Inline/Context.hs

@@ -319,8 +319,6 @@ foreignPointers = do
     foreignPtrT <- [t|ForeignPtr|]
     pure $ Context ([rule], [rev foreignPtrT], [foreignPtr, constPtr, mutPtr])
   where
-    rule (Ptr _ t _) context
-        | First (Just (t', Nothing)) <- lookupRTypeInContext t context = pure ([t|ForeignPtr $t'|], Nothing)
     rule (Rptr _ _ t _) context
         | First (Just (t', Nothing)) <- lookupRTypeInContext t context = pure ([t|ForeignPtr $t'|], Nothing)
     rule (PathTy Nothing (Path False [PathSegment "ForeignPtr" (Just (AngleBracketed [] [t] [] _)) _] _) _) context
@@ -330,10 +328,6 @@ foreignPointers = do
             pure ([t|Maybe (ForeignPtr $t')|], pure . pure $ PathTy Nothing (Path False [PathSegment "ForeignPtr" (Just (AngleBracketed [] [t] [] ())) ()] ()) ())
     rule _ _ = mempty
 
-    rev foreignPtrT (AppT foreignPtr t) context
-        | foreignPtr == foreignPtrT = do
-            t' <- lookupHTypeInContext t context
-            pure (Ptr Mutable <$> t' <*> pure ())
     rev _ _ _ = mempty
 
     foreignPtr =
@@ -344,11 +338,7 @@ foreignPointers = do
 
     constPtr =
         unlines
-            [ "impl<T> MarshalInto<*const T> for *const T {"
-            , "  fn marshal(self) -> *const T { self }"
-            , "}"
-            , ""
-            , "impl<'a, T> MarshalInto<&'a T> for &'a T {"
+            [ "impl<'a, T> MarshalInto<&'a T> for &'a T {"
             , "  fn marshal(self) -> &'a T { self }"
             , "}"
             ]
@@ -378,10 +368,6 @@ foreignPointers = do
             , "  }"
             , "}"
             , ""
-            , "impl<T> MarshalInto<*mut T> for *mut T {"
-            , "  fn marshal(self) -> *mut T { self }"
-            , "}"
-            , ""
             , "impl<'a, T> MarshalInto<&'a mut T> for &'a mut T {"
             , "  fn marshal(self) -> &'a mut T { self }"
             , "}"

tests/ForeignPtr.hs

@@ -14,18 +14,13 @@ import Foreign.Ptr
 import Test.Hspec
 
 extendContext foreignPointers
+extendContext pointers
 extendContext prelude
 extendContext basic
 setCrateModule
 
 foreignPtrTypes :: Spec
 foreignPtrTypes = describe "ForeignPtr types" $ do
-    it "Can marshal ForeignPtr arguments" $ do
-        p <- mallocForeignPtr
-        withForeignPtr p (`poke` 42)
-        let read = [rust| u64 { unsafe { *$(p: *const u64) } } |]
-        42 `shouldBe` read
-
     it "Can marshal ForeignPtr arguments as references" $ do
         p <- mallocForeignPtr
         withForeignPtr p (`poke` 42)
@@ -46,14 +41,6 @@ foreignPtrTypes = describe "ForeignPtr types" $ do
         prev `shouldBe` 42
         withForeignPtr p peek >>= (`shouldBe` 43)
 
-    it "Can mutate ForeignPtr arguments" $ do
-        p <- mallocForeignPtr
-        [rustIO| () {
-            unsafe { *$(p: *mut u64) = 42; }
-        } |]
-        val <- withForeignPtr p peek
-        val `shouldBe` 42
-
     it "Can marshal ForeignPtr returns" $ do
         let p = [rust| ForeignPtr<u64> { Box::new(42).into() }|]
         val <- withForeignPtr p peek
@@ -71,3 +58,16 @@ foreignPtrTypes = describe "ForeignPtr types" $ do
                     Some(Box::new(42).into())
                 } |]
         withForeignPtr (fromJust mp) peek >>= (`shouldBe` 42)
+
+    it "still has working pointers" $
+        alloca $ \p -> do
+            [rustIO| () {
+                unsafe { *$(p: *mut u64) = 42; }
+            } |]
+            peek p >>= (`shouldBe` 42)
+
+            val <-
+                [rustIO| u64 {
+                    unsafe { *$(p: *u64) }
+                } |]
+            val `shouldBe` 42