Auto merge of #285 - tsliang:issue-125, r=emilio

clang::Cursor::enum_type should return an Option<Type>

Returning an Option<Type> relieves callers from having to check whether clang::Cursor::enum_type returns `CXType_Invalid`.

Fixes #125

2 files changed, 7 insertions, 5 deletions

diff --git a/libbindgen/src/clang.rs b/libbindgen/src/clang.rs
index a11903aa..72069644 100644
--- a/libbindgen/src/clang.rs
+++ b/libbindgen/src/clang.rs
@@ -362,11 +362,12 @@ impl Cursor {
 
     /// Get the integer representation type used to hold this cursor's referent
     /// enum type.
-    pub fn enum_type(&self) -> Type {
+    pub fn enum_type(&self) -> Option<Type> {
         unsafe {
-            Type {
+            let t = Type {
                 x: clang_getEnumDeclIntegerType(self.x),
-            }
+            };
+            if t.is_valid() { Some(t) } else { None }
         }
     }
 
diff --git a/libbindgen/src/ir/enum_ty.rs b/libbindgen/src/ir/enum_ty.rs
index 6085833d..f728b22a 100644
--- a/libbindgen/src/ir/enum_ty.rs
+++ b/libbindgen/src/ir/enum_ty.rs
@@ -49,8 +49,9 @@ impl Enum {
         }
 
         let declaration = ty.declaration().canonical();
-        let repr = Item::from_ty(&declaration.enum_type(), None, None, ctx)
-            .ok();
+        let repr = declaration.enum_type().and_then(|et| {
+            Item::from_ty(&et, None, None, ctx).ok()
+        });
         let mut variants = vec![];
 
         let is_signed = match repr {