Fix kotlin trait method and cb struct and enum returns

tool/src/kotlin/mod.rs

@@ -1075,6 +1075,18 @@ returnVal.option() ?: return null
                             _ => (in_name.clone(), format!("{}: {}", in_name, in_ty)),
                         })
                         .unzip();
+                    let (native_output_type, return_modification) = match **output {
+                        Some(ref ty) => (
+                            self.gen_native_type_name(ty, None).into(),
+                            match ty {
+                                Type::Enum(..) => ".toNative()",
+                                Type::Struct(..) => ".nativeStruct",
+                                _ => "",
+                            }
+                            .into(),
+                        ),
+                        None => ("Unit".into(), "".into()),
+                    };
                     self.callback_params.push(CallbackParamInfo {
                         name: "DiplomatCallback_".to_owned() + &additional_name.clone().unwrap(),
                         input_types: param_input_types.join(", "),
@@ -1084,6 +1096,8 @@ returnVal.option() ?: return null
                         },
                         native_input_params_and_types: native_input_params_and_types.join(", "),
                         native_input_names: native_input_names.join(", "),
+                        native_output_type,
+                        return_modification,
                     })
                 }
                 _ => (),
@@ -1533,12 +1547,26 @@ returnVal.option() ?: return null
                     + (if !cur.is_empty() { ", " } else { "" })
                     + &format!("{}: {}", in_name, in_ty)
             });
+        let (native_output_type, return_modification) = match *method.output {
+            Some(ref ty) => (
+                self.gen_native_type_name(ty, None).into(),
+                match ty {
+                    Type::Enum(..) => ".toNative()",
+                    Type::Struct(..) => ".nativeStruct",
+                    _ => "",
+                }
+                .into(),
+            ),
+            None => ("Unit".into(), "".into()),
+        };
         TraitMethodInfo {
             name: method_name,
             output_type: match *method.output {
                 Some(ref ty) => self.gen_type_name(ty, None).into(),
                 None => "Unit".into(),
             },
+            native_output_type,
+            return_modification,
             input_params_and_types: native_input_params_and_types.join(", "),
             non_native_params_and_types,
             input_params: native_input_names.join(", "),
@@ -1917,6 +1945,8 @@ struct TraitMethodInfo {
     input_params_and_types: String,
     input_params: String,
     output_type: String,
+    native_output_type: String,
+    return_modification: String,
     non_native_params_and_types: String,
 }
 
@@ -1928,6 +1958,8 @@ struct CallbackParamInfo {
     native_input_params_and_types: String,
     native_input_names: String,
     output_type: String,
+    native_output_type: String,
+    return_modification: String,
 }
 
 #[cfg(test)]
@@ -2299,11 +2331,17 @@ mod test {
                     x: i32,
                     y: i32,
                 }
+                pub enum TraitTestingEnum {
+                    One,
+                    Two,
+                }
                 pub trait TesterTrait {
                     fn test_trait_fn(&self, x: i32, y: i32, z: u8) -> i32;
                     fn test_void_trait_fn(&self);
                     fn test_struct_trait_fn(&self, s: TraitTestingStruct) -> i32;
                     fn test_with_slices(&mut self, a: &[u8], b: &[i16]) -> i32;
+                    fn test_struct_return(&self) -> TraitTestingStruct;
+                    fn test_enum_return(&self) -> TraitTestingEnum;
                 }
                 pub struct Wrapper {
                     cant_be_empty: bool,

tool/src/kotlin/snapshots/diplomat_tool__kotlin__test__trait_gen.snap

@@ -1,6 +1,6 @@
 ---
 source: tool/src/kotlin/mod.rs
-assertion_line: 2335
+assertion_line: 2380
 expression: result
 ---
 package dev.gigapixel.somelib
@@ -16,6 +16,8 @@ interface TesterTrait {
     fun testVoidTraitFn(): Unit;
     fun testStructTraitFn(s: TraitTestingStruct): Int;
     fun testWithSlices(a: UByteArray, b: ShortArray): Int;
+    fun testStructReturn(): TraitTestingStruct;
+    fun testEnumReturn(): TraitTestingEnum;
 }
 
 
@@ -31,6 +33,12 @@ internal interface Runner_DiplomatTraitMethod_TesterTrait_testStructTraitFn: Cal
 internal interface Runner_DiplomatTraitMethod_TesterTrait_testWithSlices: Callback {
     fun invoke(ignored: Pointer?, a: Slice, b: Slice ): Int
 }
+internal interface Runner_DiplomatTraitMethod_TesterTrait_testStructReturn: Callback {
+    fun invoke(ignored: Pointer?): TraitTestingStructNative
+}
+internal interface Runner_DiplomatTraitMethod_TesterTrait_testEnumReturn: Callback {
+    fun invoke(ignored: Pointer?): Int
+}
 
 internal object TesterTrait_VTable_destructor: Callback {
     fun invoke(obj_pointer: Pointer) {
@@ -74,9 +82,23 @@ internal class DiplomatTrait_TesterTrait_VTable_Native: Structure(), Structure.B
                     throw Exception("ERROR NOT IMPLEMENTED")
                 }
             }
+    @JvmField
+    internal var run_testStructReturn_callback: Runner_DiplomatTraitMethod_TesterTrait_testStructReturn
+        = object :  Runner_DiplomatTraitMethod_TesterTrait_testStructReturn {
+                override fun invoke(ignored: Pointer?): TraitTestingStructNative {
+                    throw Exception("ERROR NOT IMPLEMENTED")
+                }
+            }
+    @JvmField
+    internal var run_testEnumReturn_callback: Runner_DiplomatTraitMethod_TesterTrait_testEnumReturn
+        = object :  Runner_DiplomatTraitMethod_TesterTrait_testEnumReturn {
+                override fun invoke(ignored: Pointer?): Int {
+                    throw Exception("ERROR NOT IMPLEMENTED")
+                }
+            }
     // Define the fields of the struct
     override fun getFieldOrder(): List<String> {
-        return listOf("destructor", "size", "alignment", "run_testTraitFn_callback", "run_testVoidTraitFn_callback", "run_testStructTraitFn_callback", "run_testWithSlices_callback")
+        return listOf("destructor", "size", "alignment", "run_testTraitFn_callback", "run_testVoidTraitFn_callback", "run_testStructTraitFn_callback", "run_testWithSlices_callback", "run_testStructReturn_callback", "run_testEnumReturn_callback")
     }
 }
 
@@ -129,6 +151,18 @@ internal class DiplomatTrait_TesterTrait_Wrapper internal constructor (
                 }
             }
             vtable.run_testWithSlices_callback = testWithSlices;
+            val testStructReturn: Runner_DiplomatTraitMethod_TesterTrait_testStructReturn = object :  Runner_DiplomatTraitMethod_TesterTrait_testStructReturn {
+                override fun invoke(ignored: Pointer?): TraitTestingStructNative {
+                    return trt_obj.testStructReturn().nativeStruct;
+                }
+            }
+            vtable.run_testStructReturn_callback = testStructReturn;
+            val testEnumReturn: Runner_DiplomatTraitMethod_TesterTrait_testEnumReturn = object :  Runner_DiplomatTraitMethod_TesterTrait_testEnumReturn {
+                override fun invoke(ignored: Pointer?): Int {
+                    return trt_obj.testEnumReturn().toNative();
+                }
+            }
+            vtable.run_testEnumReturn_callback = testEnumReturn;
             val native_wrapper = DiplomatTrait_TesterTrait_Wrapper_Native();
             native_wrapper.vtable = vtable;
             native_wrapper.data_ = DiplomatJVMRuntime.buildRustCookie(vtable as Object);

tool/templates/kotlin/Callback.kt.jinja

@@ -1,6 +1,6 @@
 
 internal interface Runner_{{name}}: Callback {
-    fun invoke(lang_specific_context: Pointer?{% if native_input_params_and_types != "" %}, {{native_input_params_and_types}} {% endif %}): {{output_type}}
+    fun invoke(lang_specific_context: Pointer?{% if native_input_params_and_types != "" %}, {{native_input_params_and_types}} {% endif %}): {{native_output_type}}
 }
 
 internal class {{name}}_Native: Structure(), Structure.ByValue {
@@ -9,7 +9,7 @@ internal class {{name}}_Native: Structure(), Structure.ByValue {
     @JvmField
     internal var run_callback: Runner_{{name}}
         = object :  Runner_{{name}} {
-                override fun invoke(lang_specific_context: Pointer?{% if input_types != "" %}, {{native_input_params_and_types}} {% endif %}): {{output_type}} {
+                override fun invoke(lang_specific_context: Pointer?{% if input_types != "" %}, {{native_input_params_and_types}} {% endif %}): {{native_output_type}} {
                     throw Exception("Default callback runner -- should be replaced.")
                 }
             }
@@ -37,8 +37,8 @@ internal class {{name}} internal constructor (
 
         fun fromCallback(cb: ({{input_types}})->{{output_type}}): {{name}} {
             val callback: Runner_{{name}} = object :  Runner_{{name}} {
-                override fun invoke(lang_specific_context: Pointer?{% if input_types != "" %}, {{native_input_params_and_types}} {% endif %}): {{output_type}} {
-                    return cb({{native_input_names}});
+                override fun invoke(lang_specific_context: Pointer?{% if input_types != "" %}, {{native_input_params_and_types}} {% endif %}): {{native_output_type}} {
+                    return cb({{native_input_names}}){{return_modification}};
                 }
             }
             val cb_wrap = {{name}}_Native()

tool/templates/kotlin/Trait.kt.jinja

@@ -21,7 +21,7 @@ interface {{trait_name}} {
 {% if !trait_methods.is_empty() -%}
     {%- for trait_method in trait_methods %}
 internal interface Runner_DiplomatTraitMethod_{{trait_name}}_{{trait_method.name}}: Callback {
-    fun invoke(ignored: Pointer?{% if trait_method.input_params_and_types != "" %}, {{trait_method.input_params_and_types}} {% endif %}): {{trait_method.output_type}}
+    fun invoke(ignored: Pointer?{% if trait_method.input_params_and_types != "" %}, {{trait_method.input_params_and_types}} {% endif %}): {{trait_method.native_output_type}}
 }
     {%- endfor %}
 {%- endif %}
@@ -44,7 +44,7 @@ internal class DiplomatTrait_{{trait_name}}_VTable_Native: Structure(), Structur
     @JvmField
     internal var run_{{trait_method.name}}_callback: Runner_DiplomatTraitMethod_{{trait_name}}_{{trait_method.name}}
         = object :  Runner_DiplomatTraitMethod_{{trait_name}}_{{trait_method.name}} {
-                override fun invoke(ignored: Pointer?{% if trait_method.input_params_and_types != "" %}, {{trait_method.input_params_and_types}} {% endif %}): {{trait_method.output_type}} {
+                override fun invoke(ignored: Pointer?{% if trait_method.input_params_and_types != "" %}, {{trait_method.input_params_and_types}} {% endif %}): {{trait_method.native_output_type}} {
                     throw Exception("ERROR NOT IMPLEMENTED")
                 }
             }
@@ -84,8 +84,8 @@ internal class DiplomatTrait_{{trait_name}}_Wrapper internal constructor (
             {% if !trait_methods.is_empty() -%}
                 {%- for trait_method in trait_methods %}
             val {{trait_method.name}}: Runner_DiplomatTraitMethod_{{trait_name}}_{{trait_method.name}} = object :  Runner_DiplomatTraitMethod_{{trait_name}}_{{trait_method.name}} {
-                override fun invoke(ignored: Pointer?{% if trait_method.input_params_and_types != "" %}, {{trait_method.input_params_and_types}} {% endif %}): {{trait_method.output_type}} {
-                    return trt_obj.{{trait_method.name}}({{trait_method.input_params}});
+                override fun invoke(ignored: Pointer?{% if trait_method.input_params_and_types != "" %}, {{trait_method.input_params_and_types}} {% endif %}): {{trait_method.native_output_type}} {
+                    return trt_obj.{{trait_method.name}}({{trait_method.input_params}}){{trait_method.return_modification}};
                 }
             }
             vtable.run_{{trait_method.name}}_callback = {{trait_method.name}};