2 files changed, 65 insertions, 11 deletions

diff --git a/src/de.rs b/src/de.rs
index 0e08bf1..248096a 100644
--- a/src/de.rs
+++ b/src/de.rs
@@ -568,10 +568,19 @@ impl de::Deserializer for LevelDeserializer {
     fn deserialize<V>(self, visitor: V) -> Result<V::Value, Self::Error>
         where V: de::Visitor,
     {
-        if let Level::Flat(x) = self.0 {
-            x.into_deserializer().deserialize(visitor)
-        } else {
-            Err(de::Error::custom("cannot deserialize value"))
+        match self.0 {
+            Level::Nested(map) => {
+                Deserializer::with_map(map).deserialize_map(visitor)
+            },
+            Level::Sequence(seq) => {
+                SeqDeserializer::new(seq.into_iter()).deserialize(visitor)
+            },
+            Level::Flat(x) => {
+                x.into_deserializer().deserialize(visitor)
+            },
+            Level::Invalid(e) => {
+                Err(de::Error::custom(e))
+            }
         }
     }
 
@@ -631,14 +640,12 @@ impl de::Deserializer for LevelDeserializer {
         where V: de::Visitor,
     {
         match self.0 {
-            Level::Flat(x) => {
-                if x == "" {
-                    visitor.visit_none()
-                } else {
-                    visitor.visit_some(x.into_deserializer())
-                }
+            Level::Flat(ref x) if x == "" => {
+                visitor.visit_none()
+            },
+            _ => {
+                visitor.visit_some(self)
             },
-            _ => Err(de::Error::custom("value does not appear to be a value")),
         }
     }
 
diff --git a/tests/test_deserialize.rs b/tests/test_deserialize.rs
index dc93bd5..9ef164c 100644
--- a/tests/test_deserialize.rs
+++ b/tests/test_deserialize.rs
@@ -192,3 +192,50 @@ fn qs_nesting() {
     map_test!("a[b][c][d][e][f][g][h]=i",
               "a"["b"["c"["d"["e"["[f][g][h]"["i"]]]]]]);
 }
+
+#[test]
+fn optional_seq() {
+    #[derive(Debug,Serialize,Deserialize,PartialEq)]
+    struct Query {
+        vec: Option<Vec<u8>>,
+    }
+
+    let params = "vec=";
+    let query = Query {
+        vec: None,
+    };
+    let rec_params: Query = qs::from_str(params).unwrap();
+    assert_eq!(rec_params, query);
+
+    let params = "vec[0]=1&vec[1]=2";
+    let query = Query {
+        vec: Some(vec![1,2]),
+    };
+    let rec_params: Query = qs::from_str(params).unwrap();
+    assert_eq!(rec_params, query);
+}
+
+#[test]
+fn optional_struct() {
+    #[derive(Debug,Serialize,Deserialize,PartialEq)]
+    struct Query {
+        address: Option<Address>,
+    }
+
+    let params = "address=";
+    let query = Query {
+        address: None,
+    };
+    let rec_params: Query = qs::from_str(params).unwrap();
+    assert_eq!(rec_params, query);
+
+    let params = "address[city]=Carrot+City&address[postcode]=12345";
+    let query = Query {
+        address: Some(Address {
+            city: "Carrot City".to_string(),
+            postcode: "12345".to_string(),
+        },),
+    };
+    let rec_params: Query = qs::from_str(params).unwrap();
+    assert_eq!(rec_params, query);
+}