Add null_as_nil option to json/yaml decode

Author: khvzak

src/json.rs

@@ -192,12 +192,18 @@ struct LuaJsonMapIter {
 ///
 /// The optional `opts` table can contain:
 /// - `set_array_metatable` (boolean): If true, sets a metatable for arrays. Default is false.
+/// - `null_as_nil` (boolean): If true, `null`s will be represented as Lua `nil`. Default is false.
 pub fn decode(lua: &Lua, (data, opts): (StringOrBytes, Option<Table>)) -> Result<StdResult<Value, String>> {
     let opts = opts.as_ref();
     let mut options = SerializeOptions::new();
-    if let Some(enabled) = opts.and_then(|t| t.get::<bool>("set_array_metatable").ok()) {
+    if let Some(enabled) = opts.and_then(|t| t.raw_get::<bool>("set_array_metatable").ok()) {
         options = options.set_array_metatable(enabled);
     }
+    if let Some(enabled) = opts.and_then(|t| t.raw_get::<bool>("null_as_nil").ok()) {
+        options = options
+            .serialize_unit_to_null(!enabled)
+            .serialize_none_to_null(!enabled);
+    }
 
     let json: serde_json::Value = lua_try!(serde_json::from_slice(&data.as_bytes_deref()));
     Ok(Ok(lua.to_value_with(&json, options)?))
@@ -220,11 +226,11 @@ pub fn encode(value: Value, opts: Option<Table>) -> StdResult<String, String> {
     let mut value = value.to_serializable();
     let opts = opts.as_ref();
 
-    if opts.and_then(|t| t.get::<bool>("relaxed").ok()) == Some(true) {
+    if opts.and_then(|t| t.raw_get::<bool>("relaxed").ok()) == Some(true) {
         value = value.deny_recursive_tables(false).deny_unsupported_types(false);
     }
 
-    if opts.and_then(|t| t.get::<bool>("pretty").ok()) == Some(true) {
+    if opts.and_then(|t| t.raw_get::<bool>("pretty").ok()) == Some(true) {
         value = value.sort_keys(true);
         return serde_json::to_string_pretty(&value).map_err(|e| e.to_string());
     }

src/yaml.rs

@@ -198,12 +198,18 @@ struct LuaYamlMapIter {
 ///
 /// The `opts` table can contain the following options:
 /// - `set_array_metatable` (boolean): If true, sets a metatable for arrays. Default is false.
+/// - `null_as_nil` (boolean): If true, `null`s will be represented as Lua `nil`. Default is false.
 pub fn decode(lua: &Lua, (data, opts): (StringOrBytes, Option<Table>)) -> Result<StdResult<Value, String>> {
     let opts = opts.as_ref();
     let mut options = SerializeOptions::new();
-    if let Some(enabled) = opts.and_then(|t| t.get::<bool>("set_array_metatable").ok()) {
+    if let Some(enabled) = opts.and_then(|t| t.raw_get::<bool>("set_array_metatable").ok()) {
         options = options.set_array_metatable(enabled);
     }
+    if let Some(enabled) = opts.and_then(|t| t.raw_get::<bool>("null_as_nil").ok()) {
+        options = options
+            .serialize_unit_to_null(!enabled)
+            .serialize_none_to_null(!enabled);
+    }
 
     let mut yaml: serde_yaml::Value = lua_try!(serde_yaml::from_slice(&data.as_bytes_deref()));
     lua_try!(yaml.apply_merge());
@@ -227,7 +233,7 @@ pub fn encode(value: Value, opts: Option<Table>) -> StdResult<String, String> {
     let opts = opts.as_ref();
     let mut value = value.to_serializable();
 
-    if opts.and_then(|t| t.get::<bool>("relaxed").ok()) == Some(true) {
+    if opts.and_then(|t| t.raw_get::<bool>("relaxed").ok()) == Some(true) {
         value = value.deny_recursive_tables(false).deny_unsupported_types(false);
     }
 

tests/lua/json_tests.lua

@@ -37,6 +37,15 @@ testing:test("decode", function(t)
     t.assert_eq(err, nil)
     t.assert_eq(type(value), "table", "value is not a table")
     t.assert_eq(getmetatable(value), nil, "array metatable is set")
+
+    -- Test null_as_nil option
+    value = json.decode('{"a": null, "b": 1}')
+    t.assert_eq(type(value.a), "userdata", "null should be userdata by default")
+    t.assert_eq(value.b, 1)
+
+    value = json.decode('{"a": null, "b": 1}', { null_as_nil = true })
+    t.assert_eq(value.a, nil, "null should be nil when null_as_nil is true")
+    t.assert_eq(value.b, 1)
 end)
 
 -- Test decode to native object

tests/lua/yaml_tests.lua

@@ -35,6 +35,20 @@ testing:test("decode", function(t)
     t.assert_eq(err, nil)
     t.assert_eq(value.key, "value")
     t.assert_eq(value.number, 42)
+
+    -- Test null_as_nil option
+    value = yaml.decode("a: null\nb: 1")
+    t.assert_eq(type(value.a), "userdata", "null should be userdata by default")
+    t.assert_eq(value.b, 1)
+
+    value = yaml.decode("a: null\nb: 1", { null_as_nil = true })
+    t.assert_eq(value.a, nil, "null should be nil when null_as_nil is true")
+    t.assert_eq(value.b, 1)
+
+    -- Test with alternative YAML null representations
+    value = yaml.decode("a: ~\nb: 1", { null_as_nil = true })
+    t.assert_eq(value.a, nil, "~ should be nil when null_as_nil is true")
+    t.assert_eq(value.b, 1)
 end)
 
 -- Test decode to native object