fix #48 return poped element on arr_pop (#52)

* fix #48 return poped element on arr_pop

Author: gkorland

src/lib.rs

@@ -529,9 +529,9 @@ fn json_arr_pop(ctx: &Context, args: Vec<String>) -> RedisResult {
         .ok_or_else(RedisError::nonexistent_key)
         .and_then(|doc| {
             doc.value_op(&path, |value| do_json_arr_pop(index, &mut res, value))
-                .map(|v| v.to_string().into())
                 .map_err(|e| e.into())
-        })
+        })?;
+    Ok(RedisJSON::serialize(&res, Format::JSON)?.into())
 }
 
 fn do_json_arr_pop(mut index: i64, res: &mut Value, value: &Value) -> Result<Value, Error> {

src/redisjson.rs

@@ -155,8 +155,12 @@ impl RedisJSON {
 
     pub fn to_string(&self, path: &str, format: Format) -> Result<String, Error> {
         let results = self.get_doc(path)?;
+        Self::serialize(results, format)
+    }
+
+    pub fn serialize(results: &Value, format: Format) -> Result<String, Error> {
         let res = match format {
-            Format::JSON => serde_json::to_string(&results)?,
+            Format::JSON => serde_json::to_string(results)?,
             Format::BSON => return Err("Soon to come...".into()), //results.into() as Bson,
         };
         Ok(res)