fix add_fields population

Cargo.lock

@@ -185,6 +185,7 @@ dependencies = [
  "base64",
  "convert_case",
  "lazy_static",
+ "macros",
  "oapi",
  "oas3",
  "openapi3-parser",
@@ -521,6 +522,15 @@ dependencies = [
  "logos-codegen",
 ]
 
+[[package]]
+name = "macros"
+version = "0.1.0"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.90",
+]
+
 [[package]]
 name = "memchr"
 version = "2.7.4"

Cargo.toml

@@ -21,3 +21,7 @@ wit-parser = "0.222.0"
 lazy_static = "1.5.0"
 base64 = "0.22.1"
 strum_macros = "0.26.4"
+macros = {path = "macros"}
+
+[workspace]
+members = [".", "macros"]

macros/Cargo.lock

@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "macros"
+version = "0.1.0"

macros/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "macros"
+version = "0.1.0"
+edition = "2021"
+
+[lib]
+proc-macro = true
+
+[dependencies]
+syn = { version = "2.0.60", features = ["derive", "full"] }
+quote = "1.0.36"
+proc-macro2 = "1.0.81"

macros/src/lib.rs

@@ -0,0 +1,9 @@
+use proc_macro::TokenStream;
+
+mod merge_right;
+
+use crate::merge_right::expand_merge_right_derive;
+#[proc_macro_derive(MergeRight, attributes(merge_right))]
+pub fn merge_right_derive(input: TokenStream) -> TokenStream {
+    expand_merge_right_derive(input)
+}

macros/src/merge_right.rs

@@ -0,0 +1,186 @@
+extern crate proc_macro;
+
+use proc_macro::TokenStream;
+use quote::quote;
+use syn::spanned::Spanned;
+use syn::{parse_macro_input, Data, DeriveInput, Fields, Index};
+
+const MERGE_RIGHT_FN: &str = "merge_right_fn";
+const MERGE_RIGHT: &str = "merge_right";
+
+#[derive(Default)]
+struct Attrs {
+    merge_right_fn: Option<syn::ExprPath>,
+}
+
+fn get_attrs(attrs: &[syn::Attribute]) -> syn::Result<Attrs> {
+    let mut attrs_ret = Attrs::default();
+    for attr in attrs {
+        if attr.path().is_ident(MERGE_RIGHT) {
+            attr.parse_nested_meta(|meta| {
+                if meta.path.is_ident(MERGE_RIGHT_FN) {
+                    let p: syn::Expr = meta.value()?.parse()?;
+                    let lit =
+                        if let syn::Expr::Lit(syn::ExprLit { lit: syn::Lit::Str(lit), .. }) = p {
+                            let suffix = lit.suffix();
+                            if !suffix.is_empty() {
+                                return Err(syn::Error::new(
+                                    lit.span(),
+                                    format!("unexpected suffix `{}` on string literal", suffix),
+                                ));
+                            }
+                            lit
+                        } else {
+                            return Err(syn::Error::new(
+                                p.span(),
+                                format!(
+                                    "expected merge_right {} attribute to be a string.",
+                                    MERGE_RIGHT_FN
+                                ),
+                            ));
+                        };
+                    let expr_path: syn::ExprPath = lit.parse()?;
+                    attrs_ret.merge_right_fn = Some(expr_path);
+                    Ok(())
+                } else {
+                    Err(syn::Error::new(attr.span(), "Unknown helper attribute."))
+                }
+            })?;
+        }
+    }
+    Ok(attrs_ret)
+}
+
+pub fn expand_merge_right_derive(input: TokenStream) -> TokenStream {
+    let input = parse_macro_input!(input as DeriveInput);
+
+    let name = input.ident.clone();
+    let generics = input.generics.clone();
+    let gen = match input.data {
+        // Implement for structs
+        Data::Struct(data) => {
+            let fields = match &data.fields {
+                Fields::Named(fields) => &fields.named,
+                Fields::Unnamed(fields) => &fields.unnamed,
+                Fields::Unit => {
+                    return quote! {
+                        impl crate::merge_right::MergeRight for #name {
+                            fn merge_right(self, other: Self) -> Self {
+                                other
+                            }
+                        }
+                    }
+                    .into()
+                }
+            };
+
+            let merge_logic = fields.iter().enumerate().map(|(i, f)| {
+                let attrs = get_attrs(&f.attrs);
+                if let Err(err) = attrs {
+                    panic!("{}", err);
+                }
+                let attrs = attrs.unwrap();
+                let name = &f.ident;
+
+                match &data.fields {
+                    Fields::Named(_) => {
+                        if let Some(merge_right_fn) = attrs.merge_right_fn {
+                            quote! {
+                                #name: #merge_right_fn(self.#name, other.#name),
+                            }
+                        } else {
+                            quote! {
+                                #name: self.#name.merge_right(other.#name),
+                            }
+                        }
+                    }
+                    Fields::Unnamed(_) => {
+                        let name = Index::from(i);
+                        if let Some(merge_right_fn) = attrs.merge_right_fn {
+                            quote! {
+                                #merge_right_fn(self.#name, other.#name),
+                            }
+                        } else {
+                            quote! {
+                                self.#name.merge_right(other.#name),
+                            }
+                        }
+                    }
+                    Fields::Unit => unreachable!(),
+                }
+            });
+
+            let generics_lt = generics.lt_token;
+            let generics_gt = generics.gt_token;
+            let generics_params = generics.params;
+
+            let generics_del = quote! {
+                #generics_lt #generics_params #generics_gt
+            };
+
+            let initializer = match data.fields {
+                Fields::Named(_) => quote! {
+                    Self {
+                        #(#merge_logic)*
+                    }
+                },
+                Fields::Unnamed(_) => quote! {
+                    Self(#(#merge_logic)*)
+                },
+                Fields::Unit => unreachable!(),
+            };
+
+            quote! {
+                impl #generics_del crate::merge_right::MergeRight for #name #generics_del {
+                    fn merge_right(self, other: Self) -> Self {
+                        #initializer
+                    }
+                }
+            }
+        }
+        // Implement for enums
+        Data::Enum(_) => quote! {
+            impl crate::merge_right::MergeRight for #name {
+                fn merge_right(self, other: Self) -> Self {
+                    other
+                }
+            }
+        },
+        // Optionally handle or disallow unions
+        Data::Union(_) => {
+            return syn::Error::new_spanned(input, "Union types are not supported by MergeRight")
+                .to_compile_error()
+                .into()
+        }
+    };
+
+    gen.into()
+}
+
+#[cfg(test)]
+mod tests {
+    use syn::{parse_quote, Attribute};
+
+    use super::*;
+
+    #[test]
+    fn test_get_attrs_invalid_type() {
+        let attrs: Vec<Attribute> = vec![parse_quote!(#[merge_right(merge_right_fn = 123)])];
+        let result = get_attrs(&attrs);
+        assert!(
+            result.is_err(),
+            "Expected error with non-string type for `merge_right_fn`"
+        );
+    }
+
+    #[test]
+    fn test_get_attrs_unexpected_suffix() {
+        let attrs: Vec<Attribute> =
+            vec![parse_quote!(#[merge_right(merge_right_fn = "some_fn()")])];
+        let result = get_attrs(&attrs);
+        assert!(
+            result.is_err(),
+            "Expected error with unexpected suffix on string literal"
+        );
+    }
+}

src/config/config.rs

@@ -1,13 +1,16 @@
+use std::collections::BTreeSet;
+use serde::{Deserialize, Serialize};
+use macros::MergeRight;
 use crate::config::wit_types::WitType;
 
-#[derive(Debug, Clone, Default, PartialEq, Eq)]
+#[derive(Debug, Clone, Default, PartialEq, Eq, Serialize, Deserialize, MergeRight)]
 pub struct Config {
     pub package: String,
-    pub interfaces: Vec<Interface>,
+    pub interfaces: BTreeSet<Interface>,
     pub world: World,
 }
 
-#[derive(Debug, Clone, Default, PartialEq, Eq)]
+#[derive(Debug, Clone, Default, PartialEq, Eq, Serialize, Deserialize, MergeRight)]
 pub struct World {
     pub name: String,
     pub uses: Vec<UseStatement>,
@@ -15,47 +18,84 @@ pub struct World {
     pub exports: Vec<Interface>,
 }
 
-#[derive(Debug, Clone, Default, PartialEq, Eq)]
+#[derive(Debug, Clone, Default, PartialEq, Eq, Serialize, Deserialize, MergeRight)]
 pub struct Interface {
     pub name: String,
-    pub records: Vec<Record>,
+    pub records: BTreeSet<Record>,
     pub uses: Vec<UseStatement>,
     pub functions: Vec<Function>,
 }
 
-#[derive(Debug, Clone, Default, PartialEq, Eq)]
+impl PartialOrd for Interface {
+    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
+        Some(self.name.cmp(&other.name))
+    }
+}
+
+impl Ord for Interface {
+    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
+        self.name.cmp(&other.name)
+    }
+}
+
+#[derive(Debug, Clone, Default, PartialEq, Eq, Serialize, Deserialize, MergeRight)]
 pub struct Record {
     pub name: String,
-    pub fields: Vec<Field>,
-    pub added_fields: Vec<Field>,
+    pub fields: BTreeSet<Field>,
+    pub added_fields: BTreeSet<Field>,
 }
-#[derive(Debug, Clone, Default, PartialEq, Eq)]
+
+impl PartialOrd for Record {
+    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
+        Some(self.name.cmp(&other.name))
+    }
+}
+
+impl Ord for Record {
+    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
+        self.name.cmp(&other.name)
+    }
+}
+
+#[derive(Debug, Clone, Default, PartialEq, Eq, Serialize, Deserialize, MergeRight)]
 pub struct UseStatement {
     pub name: String,
     pub items: Vec<String>,
 }
 
-#[derive(Debug, Clone, Default, PartialEq, Eq)]
+#[derive(Debug, Clone, Default, PartialEq, Eq, Serialize, Deserialize, MergeRight)]
 pub struct Function {
     pub name: String,
     pub parameters: Vec<Parameter>,
     pub return_type: ReturnTy,
 }
 
-#[derive(Debug, Clone, Default, PartialEq, Eq)]
+#[derive(Debug, Clone, Default, PartialEq, Eq, Serialize, Deserialize, MergeRight)]
 pub struct ReturnTy {
     pub return_type: String,
     pub error_type: String,
 }
 
-#[derive(Debug, Clone, Default, PartialEq, Eq)]
+#[derive(Debug, Clone, Default, PartialEq, Eq, Serialize, Deserialize, MergeRight)]
 pub struct Parameter {
     pub name: String,
     pub parameter_type: String,
 }
 
-#[derive(Debug, Clone, Default, PartialEq, Eq)]
+#[derive(Debug, Clone, Default, PartialEq, Eq, Serialize, Deserialize, MergeRight)]
 pub struct Field {
     pub name: String,
     pub field_type: WitType,
 }
+
+impl PartialOrd for Field {
+    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
+        Some(self.name.cmp(&other.name))
+    }
+}
+
+impl Ord for Field {
+    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
+        self.name.cmp(&other.name)
+    }
+}

src/config/fixargs.rs

@@ -1,7 +1,9 @@
+use std::collections::BTreeSet;
 use base64::Engine;
 use tailcall_valid::{Valid, Validator};
 use crate::config::config::{Config, Field, Interface, Record};
 use crate::config::wit_types::WitType;
+use crate::merge_right::MergeRight;
 use crate::tryfold::TryFold;
 
 pub fn fix_args(config: Config) -> Valid<Config, anyhow::Error, anyhow::Error> {
@@ -14,16 +16,22 @@ pub fn fix_args(config: Config) -> Valid<Config, anyhow::Error, anyhow::Error> {
                             fix_field()
                                 .try_fold(&(&config, interface, record, &field, &field.field_type), interface.clone())
                                 .and_then(|new_interface| {
-                                    Valid::succeed(new_interface)
+                                    Valid::succeed(Some(new_interface))
                                 })
                         } else {
-                            Valid::succeed(interface.clone())
+                            Valid::succeed(None)
                         }
                     })
                 })
             }).and_then(|x| {
-                let x = x.into_iter().flatten().into_iter().flatten().collect::<Vec<_>>();
-                config.interfaces = x;
+                let x = x.into_iter().flatten().into_iter().flatten().filter_map(|x| x).collect::<Vec<_>>();
+
+                let mut map = BTreeSet::new();
+                for interface in x {
+                    map.insert(interface);
+                }
+
+                config.interfaces = config.interfaces.merge_right(map);
 
                 Valid::succeed(config)
             })
@@ -39,7 +47,7 @@ fn fix_field<'a>() -> TryFold<'a, (&'a Config, &'a Interface, &'a Record, &'a Fi
             WitType::Result(a, b) => {
                 // TODO: this impl needs check.
                 // eg: -> result<record A {}, record B {}>
-                // this does not make sense to resolve with rec.name-field.name-A/B
+                // this does not make sense to resolve with rec.name-A/B
 
                 return if !a.is_primitive() {
                     fix_field().try_fold(&(*config, *interface, *rec, *field, a), o)
@@ -61,7 +69,26 @@ fn fix_field<'a>() -> TryFold<'a, (&'a Config, &'a Interface, &'a Record, &'a Fi
                     })));
             }
             WitType::Record(records) => {
-                for (arg_name, ty) in records {
+                let field_name = if field.name.is_empty() {
+                    base64::prelude::BASE64_STANDARD.encode(field.name.as_bytes())
+                }else {
+                    field.name.clone()
+                };
+                let name = format!("{}-{}", rec.name, field_name);
+                
+                let new_field = Field {
+                    name,
+                    field_type: WitType::Record(records.clone()),
+                };
+                let mut rec = (*rec).clone();
+                rec.added_fields.insert(new_field);
+                // let mut filtered_records = o.records.into_iter().filter(|r| r.name == rec.name).collect::<Vec<_>>();
+                // filtered_records.push(rec);
+                o.records.remove(&rec);
+                o.records.insert(rec);
+                Valid::succeed(o)
+
+/*                for (arg_name, ty) in records {
                     let arg_name = if arg_name.is_empty() {
                         // TODO: maybe we can introduce some transformers
                         // which uses AI to generate better names
@@ -71,8 +98,9 @@ fn fix_field<'a>() -> TryFold<'a, (&'a Config, &'a Interface, &'a Record, &'a Fi
                     };
 
                     let name = format!("{}-{}-{}", rec.name, field.name, arg_name);
+                    println!("name: {}", name);
                     let new_field = Field {
-                        name,
+                        name: name.clone(),
                         field_type: ty.clone(),
                     };
                     let mut rec = (*rec).clone();
@@ -80,9 +108,10 @@ fn fix_field<'a>() -> TryFold<'a, (&'a Config, &'a Interface, &'a Record, &'a Fi
                     let mut filtered_records = o.records.into_iter().filter(|r| r.name == rec.name).collect::<Vec<_>>();
                     filtered_records.push(rec);
 
+
                     o.records = filtered_records;
                 }
-                Valid::succeed(o)
+                Valid::succeed(o)*/
 
    /*             Valid::from_iter(records.iter(), |(_, b)| {
                     fix_field()

src/config/handle_files.rs

@@ -1,3 +1,4 @@
+use std::collections::BTreeSet;
 use anyhow::{anyhow, Error};
 use tailcall_valid::{Valid, Validator};
 use crate::config::config::{Config, Field, Interface, Record};
@@ -28,8 +29,8 @@ pub fn handle_types(config: Config, spec: &OpenApiSpec) -> Valid<Config, Error,
                                 .and_then(|fields| {
                                     let record = Record {
                                         name: record_name.clone(),
-                                        fields,
-                                        added_fields: vec![],
+                                        fields: fields.into_iter().collect::<BTreeSet<_>>(),
+                                        added_fields: Default::default(),
                                     };
                                     Valid::succeed(record)
                                 })
@@ -37,10 +38,10 @@ pub fn handle_types(config: Config, spec: &OpenApiSpec) -> Valid<Config, Error,
                 }).and_then(|records| {
                     let interface = Interface {
                         name: "types".to_string(),
-                        records,
+                        records: records.into_iter().collect::<BTreeSet<_>>(),
                         ..Default::default()
                     };
-                    config.interfaces.push(interface);
+                    config.interfaces.insert(interface);
                     Valid::succeed(())
                 })
             }).and_then(|_| Valid::succeed(config))

src/config/wit_types.rs

@@ -1,9 +1,10 @@
+use serde::{Deserialize, Serialize};
 use tailcall_valid::{Valid, Validator};
 use crate::config::to_wit::ToWit;
 
 use crate::ser::{OpenApiSpec, Schema};
 
-#[derive(Debug, Clone, Default, PartialEq, Eq, strum_macros::Display)]
+#[derive(Debug, Clone, Default, PartialEq, Eq, strum_macros::Display, Serialize, Deserialize)]
 pub enum WitType {
     // Primitive Types
     Bool,

src/main.rs

@@ -5,6 +5,8 @@ mod config;
 mod transformer;
 mod transform;
 mod tryfold;
+mod merge_right;
+mod primitive;
 
 use serde_json::{Map, Value};
 use anyhow::{Result, bail};

src/merge_right.rs

@@ -0,0 +1,293 @@
+use std::collections::{BTreeMap, BTreeSet, HashMap, HashSet};
+use crate::config::wit_types::WitType;
+
+pub trait MergeRight {
+    fn merge_right(self, other: Self) -> Self;
+}
+
+impl<A: MergeRight> MergeRight for Option<A> {
+    fn merge_right(self, other: Self) -> Self {
+        match (self, other) {
+            (Some(this), Some(that)) => Some(this.merge_right(that)),
+            (None, Some(that)) => Some(that),
+            (Some(this), None) => Some(this),
+            (None, None) => None,
+        }
+    }
+}
+
+impl<A> MergeRight for Vec<A> {
+    fn merge_right(mut self, other: Self) -> Self {
+        self.extend(other);
+        self
+    }
+}
+
+impl<V> MergeRight for BTreeSet<V>
+    where
+        V: Ord,
+{
+    fn merge_right(self, mut other: Self) -> Self {
+        other.extend(self);
+        other
+    }
+}
+
+impl<V> MergeRight for HashSet<V>
+    where
+        V: Eq + std::hash::Hash,
+{
+    fn merge_right(mut self, other: Self) -> Self {
+        self.extend(other);
+        self
+    }
+}
+
+impl<K, V> MergeRight for BTreeMap<K, V>
+    where
+        K: Ord,
+        V: MergeRight,
+{
+    fn merge_right(mut self, other: Self) -> Self {
+        for (other_name, mut other_value) in other {
+            if let Some(self_value) = self.remove(&other_name) {
+                other_value = self_value.merge_right(other_value);
+            }
+
+            self.insert(other_name, other_value);
+        }
+        self
+    }
+}
+
+impl<K, V> MergeRight for HashMap<K, V>
+    where
+        K: Eq + std::hash::Hash,
+        V: MergeRight,
+{
+    fn merge_right(mut self, other: Self) -> Self {
+        for (other_name, mut other_value) in other {
+            if let Some(self_value) = self.remove(&other_name) {
+                other_value = self_value.merge_right(other_value);
+            }
+
+            self.insert(other_name, other_value);
+        }
+        self
+    }
+}
+
+impl MergeRight for WitType {
+    fn merge_right(self, other: Self) -> Self {
+        other
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use std::collections::{BTreeMap, BTreeSet, HashMap, HashSet};
+
+    use serde_json::json;
+
+    use super::MergeRight;
+
+    #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Default)]
+    struct Test(u32);
+
+    impl From<u32> for Test {
+        fn from(value: u32) -> Self {
+            Self(value)
+        }
+    }
+
+    impl MergeRight for Test {
+        fn merge_right(self, other: Self) -> Self {
+            Self(self.0 + other.0)
+        }
+    }
+
+    #[test]
+    fn test_option() {
+        let x: Option<Test> = None.merge_right(None);
+        assert_eq!(x, None);
+
+        let x = Some(Test::from(1)).merge_right(None);
+        assert_eq!(x, Some(Test::from(1)));
+
+        let x = None.merge_right(Some(Test::from(2)));
+        assert_eq!(x, Some(Test::from(2)));
+
+        let x = Some(Test::from(1)).merge_right(Some(Test::from(2)));
+        assert_eq!(x, Some(Test::from(3)));
+    }
+
+    #[test]
+    fn test_vec() {
+        let l: Vec<Test> = vec![];
+        let r: Vec<Test> = vec![];
+        assert_eq!(l.merge_right(r), vec![]);
+
+        let l: Vec<Test> = vec![Test::from(1), Test::from(2)];
+        let r: Vec<Test> = vec![];
+        assert_eq!(l.merge_right(r), vec![Test::from(1), Test::from(2)]);
+
+        let l: Vec<Test> = vec![];
+        let r: Vec<Test> = vec![Test::from(3), Test::from(4)];
+        assert_eq!(l.merge_right(r), vec![Test::from(3), Test::from(4)]);
+
+        let l: Vec<Test> = vec![Test::from(1), Test::from(2)];
+        let r: Vec<Test> = vec![Test::from(3), Test::from(4)];
+        assert_eq!(
+            l.merge_right(r),
+            vec![Test::from(1), Test::from(2), Test::from(3), Test::from(4)]
+        );
+    }
+
+    #[test]
+    fn test_btree_set() {
+        let l: BTreeSet<Test> = BTreeSet::from_iter(vec![]);
+        let r: BTreeSet<Test> = BTreeSet::from_iter(vec![]);
+        assert_eq!(l.merge_right(r), BTreeSet::from_iter(vec![]));
+
+        let l: BTreeSet<Test> = BTreeSet::from_iter(vec![Test::from(1), Test::from(2)]);
+        let r: BTreeSet<Test> = BTreeSet::from_iter(vec![]);
+        assert_eq!(
+            l.merge_right(r),
+            BTreeSet::from_iter(vec![Test::from(1), Test::from(2)])
+        );
+
+        let l: BTreeSet<Test> = BTreeSet::from_iter(vec![]);
+        let r: BTreeSet<Test> = BTreeSet::from_iter(vec![Test::from(3), Test::from(4)]);
+        assert_eq!(
+            l.merge_right(r),
+            BTreeSet::from_iter(vec![Test::from(3), Test::from(4)])
+        );
+
+        let l: BTreeSet<Test> = BTreeSet::from_iter(vec![Test::from(1), Test::from(2)]);
+        let r: BTreeSet<Test> =
+            BTreeSet::from_iter(vec![Test::from(2), Test::from(3), Test::from(4)]);
+        assert_eq!(
+            l.merge_right(r),
+            BTreeSet::from_iter(vec![
+                Test::from(1),
+                Test::from(2),
+                Test::from(3),
+                Test::from(4)
+            ])
+        );
+    }
+
+    #[test]
+    fn test_hash_set() {
+        let l: HashSet<Test> = HashSet::from_iter(vec![]);
+        let r: HashSet<Test> = HashSet::from_iter(vec![]);
+        assert_eq!(l.merge_right(r), HashSet::from_iter(vec![]));
+
+        let l: HashSet<Test> = HashSet::from_iter(vec![Test::from(1), Test::from(2)]);
+        let r: HashSet<Test> = HashSet::from_iter(vec![]);
+        assert_eq!(
+            l.merge_right(r),
+            HashSet::from_iter(vec![Test::from(1), Test::from(2)])
+        );
+
+        let l: HashSet<Test> = HashSet::from_iter(vec![]);
+        let r: HashSet<Test> = HashSet::from_iter(vec![Test::from(3), Test::from(4)]);
+        assert_eq!(
+            l.merge_right(r),
+            HashSet::from_iter(vec![Test::from(3), Test::from(4)])
+        );
+
+        let l: HashSet<Test> = HashSet::from_iter(vec![Test::from(1), Test::from(2)]);
+        let r: HashSet<Test> =
+            HashSet::from_iter(vec![Test::from(2), Test::from(3), Test::from(4)]);
+        assert_eq!(
+            l.merge_right(r),
+            HashSet::from_iter(vec![
+                Test::from(1),
+                Test::from(2),
+                Test::from(3),
+                Test::from(4)
+            ])
+        );
+    }
+
+    #[test]
+    fn test_btree_map() {
+        let l: BTreeMap<u32, Test> = BTreeMap::from_iter(vec![]);
+        let r: BTreeMap<u32, Test> = BTreeMap::from_iter(vec![]);
+        assert_eq!(l.merge_right(r), BTreeMap::from_iter(vec![]));
+
+        let l: BTreeMap<u32, Test> =
+            BTreeMap::from_iter(vec![(1, Test::from(1)), (2, Test::from(2))]);
+        let r: BTreeMap<u32, Test> = BTreeMap::from_iter(vec![]);
+        assert_eq!(
+            l.merge_right(r),
+            BTreeMap::from_iter(vec![(1, Test::from(1)), (2, Test::from(2))])
+        );
+
+        let l: BTreeMap<u32, Test> = BTreeMap::from_iter(vec![]);
+        let r: BTreeMap<u32, Test> =
+            BTreeMap::from_iter(vec![(3, Test::from(3)), (4, Test::from(4))]);
+        assert_eq!(
+            l.merge_right(r),
+            BTreeMap::from_iter(vec![(3, Test::from(3)), (4, Test::from(4))])
+        );
+
+        let l: BTreeMap<u32, Test> =
+            BTreeMap::from_iter(vec![(1, Test::from(1)), (2, Test::from(2))]);
+        let r: BTreeMap<u32, Test> = BTreeMap::from_iter(vec![
+            (2, Test::from(5)),
+            (3, Test::from(3)),
+            (4, Test::from(4)),
+        ]);
+        assert_eq!(
+            l.merge_right(r),
+            BTreeMap::from_iter(vec![
+                (1, Test::from(1)),
+                (2, Test::from(7)),
+                (3, Test::from(3)),
+                (4, Test::from(4))
+            ])
+        );
+    }
+
+    #[test]
+    fn test_hash_map() {
+        let l: HashMap<u32, Test> = HashMap::from_iter(vec![]);
+        let r: HashMap<u32, Test> = HashMap::from_iter(vec![]);
+        assert_eq!(l.merge_right(r), HashMap::from_iter(vec![]));
+
+        let l: HashMap<u32, Test> =
+            HashMap::from_iter(vec![(1, Test::from(1)), (2, Test::from(2))]);
+        let r: HashMap<u32, Test> = HashMap::from_iter(vec![]);
+        assert_eq!(
+            l.merge_right(r),
+            HashMap::from_iter(vec![(1, Test::from(1)), (2, Test::from(2))])
+        );
+
+        let l: HashMap<u32, Test> = HashMap::from_iter(vec![]);
+        let r: HashMap<u32, Test> =
+            HashMap::from_iter(vec![(3, Test::from(3)), (4, Test::from(4))]);
+        assert_eq!(
+            l.merge_right(r),
+            HashMap::from_iter(vec![(3, Test::from(3)), (4, Test::from(4))])
+        );
+
+        let l: HashMap<u32, Test> =
+            HashMap::from_iter(vec![(1, Test::from(1)), (2, Test::from(2))]);
+        let r: HashMap<u32, Test> = HashMap::from_iter(vec![
+            (2, Test::from(5)),
+            (3, Test::from(3)),
+            (4, Test::from(4)),
+        ]);
+        assert_eq!(
+            l.merge_right(r),
+            HashMap::from_iter(vec![
+                (1, Test::from(1)),
+                (2, Test::from(7)),
+                (3, Test::from(3)),
+                (4, Test::from(4))
+            ])
+        );
+    }
+}

src/primitive.rs

@@ -0,0 +1,29 @@
+use std::marker::PhantomData;
+use std::num::NonZeroU64;
+
+use crate::merge_right::MergeRight;
+
+pub trait Primitive {}
+
+impl Primitive for bool {}
+impl Primitive for char {}
+impl Primitive for f32 {}
+impl Primitive for f64 {}
+impl Primitive for i16 {}
+impl Primitive for i32 {}
+impl Primitive for i64 {}
+impl Primitive for i8 {}
+impl Primitive for NonZeroU64 {}
+impl Primitive for String {}
+impl Primitive for u16 {}
+impl Primitive for u32 {}
+impl Primitive for u64 {}
+impl Primitive for u8 {}
+impl Primitive for usize {}
+impl<A> Primitive for PhantomData<A> {}
+
+impl<A: Primitive> MergeRight for A {
+    fn merge_right(self, other: Self) -> Self {
+        other
+    }
+}

src/proto.rs

@@ -29,8 +29,9 @@ mod t {
         let mut res = to_config(y).to_result();
         match res.as_mut() {
             Ok(v) => {
-                v.package = "api:todos@1.0.0".to_string();
-                println!("{}", v.to_wit());
+                println!("{}", serde_json::to_string_pretty(v).unwrap());
+                // v.package = "api:todos@1.0.0".to_string();
+                // println!("{}", v.to_wit());
                 // let mut resolve = Resolve::new();
                 // resolve.push_str("foox.wit", &v.to_wit()).expect("TODO: panic message`");
                 // println!("{:#?}", resolve);