Update code to allow struct with one generic parameter

src/data.rs

@@ -7,7 +7,8 @@ pub enum Types {
     U8, U16, U32, U64,
     Array(Box<Types>),
     Optional(Box<Types>),
-    Named(String)
+    Named(String),
+    Generic(String, Box<Types>, proc_macro2::Span)
 }
 
 #[derive(Debug, Clone, Default)]
@@ -25,7 +26,9 @@ pub struct FieldTy {
 #[derive(Debug, Clone, Default)]
 pub struct StructTy {
     pub name: String,
-    pub fields: Vec<FieldTy>
+    pub fields: Vec<FieldTy>,
+    pub generic_fields: Vec<FieldTy>,
+    pub generic_name: Option<String>
 }
 
 #[derive(Debug, Clone, Default)]

src/generators/cpp_s.rs

@@ -33,7 +33,8 @@ pub fn ty_to_str(ty: &crate::data::Types) -> String {
         Types::U64 => "std::uint64_t".into(),
         Types::Named(name) => name.into(),
         Types::Optional(inner) => format!("std::optional<{}>", ty_to_str(inner)),
-        Types::Array(inner) => format!("std::vector<{}>", ty_to_str(inner))
+        Types::Array(inner) => format!("std::vector<{}>", ty_to_str(inner)),
+        Types::Generic(_, _, _) => unreachable!()
     }
 }
 
@@ -86,7 +87,8 @@ pub fn json_write(ty: &crate::data::FieldTy) -> String {
         {}
     }}
     __w.EndArray();", inner_var_name, ty.name, inner)
-        }
+        },
+        Types::Generic(_, _, _) => unreachable!()
     }
 }
 

src/generators/ts_c.rs

@@ -12,7 +12,8 @@ pub fn ty_to_str(ty: &crate::data::Types) -> String {
         |Types::U8 | Types::U16 | Types::U32 | Types::U64 => "number".into(),
         Types::Named(name) => name.into(),
         Types::Optional(inner) => format!("({}|null)", ty_to_str(inner)),
-        Types::Array(inner) => format!("{}[]", ty_to_str(inner))
+        Types::Array(inner) => format!("{}[]", ty_to_str(inner)),
+        Types::Generic(_, _, _) => unreachable!()
     }
 }
 

src/main.rs

@@ -1,11 +1,13 @@
 mod data;
 mod generators;
 mod templates;
+mod parser;
 
+use std::collections::HashMap;
+use std::fmt::Write;
 use std::fs::File;
 use std::io::Read;
 use clap::Parser;
-use syn::spanned::Spanned;
 
 #[derive(Debug, clap::Parser)]
 struct Args {
@@ -28,141 +30,93 @@ struct GenArgs {
 static SOURCE_FILE: once_cell::sync::OnceCell<String> = once_cell::sync::OnceCell::new();
 static SOURCE: once_cell::sync::OnceCell<String> = once_cell::sync::OnceCell::new();
 
-fn parse_enum(item: &syn::ItemEnum) -> data::EnumTy {
-    data::EnumTy {
-        name: item.ident.to_string(),
-        values: item.variants.iter().enumerate().map(|(i, v) | (v.ident.to_string(), i)).collect()
+fn has_generic(ty: &mut data::Types) -> Option<&mut data::Types> {
+    use data::Types;
+    match ty {
+        Types::String | Types::Bool |
+        Types::F32 | Types::F64 |
+        Types::I8 | Types::I16 | Types::I32 | Types::I64 |
+        Types::U8 | Types::U16 | Types::U32 | Types::U64 => None,
+        Types::Array(inner) => has_generic(inner),
+        Types::Optional(inner) => has_generic(inner),
+        Types::Named(_) => None,
+        Types::Generic(_, _, _) => Some(ty)
     }
 }
 
-fn parse_type_string(ty: String) -> data::Types {
-    use data::Types::*;
-    match ty.as_str() {
-        "str" | "String" => String,
-        "bool" => Bool,
-        "f32" => F32,
-        "f64" => F64,
-        "i8" => I8,
-        "i16" => I16,
-        "i32" => I32,
-        "i64" => I64,
-        "u8" => U8,
-        "u16" => U16,
-        "u32" => U32,
-        "u64" => U64,
-        _ => Named(ty)
+pub fn gen_generic_name(ty: &data::Types) -> String {
+    use data::Types;
+    match &ty {
+        Types::String => "string".into(),
+        Types::Bool => "bool".into(),
+        Types::F32 => "f32".into(),
+        Types::F64 => "f64".into(),
+        Types::I8 => "i8".into(),
+        Types::I16 => "i16".into(),
+        Types::I32 => "i32".into(),
+        Types::I64 => "i64".into(),
+        Types::U8 => "u8".into(),
+        Types::U16 => "u16".into(),
+        Types::U32 => "u32".into(),
+        Types::U64 => "u64".into(),
+        Types::Named(name) => name.clone(),
+        Types::Optional(inner) => format!("maybe_{}", gen_generic_name(inner)),
+        Types::Array(inner) => format!("array_{}", gen_generic_name(inner)),
+        Types::Generic(_, _, span) => emit_error(Some((span.clone(), "Nested custom generics are not allowed")))
     }
 }
-
-fn parse_type(item: &syn::Type) -> data::Types {
-    match item {
-        syn::Type::Path(path) => {
-            let segments = &path.path.segments;
-            if segments.len() != 1 {
-                emit_error(item.span(), "Path segments with len != 1");
-            }
-            let segment = &segments[0];
-            if !segment.arguments.is_empty() {
-                if segment.ident.to_string() != "Option" {
-                    emit_error(item.span(), "Only Option are currently allowed to have arguments");
-                }
-                let args = match &segment.arguments {
-                    syn::PathArguments::AngleBracketed(v) => v,
-                    _ => emit_error(item.span(), "Angle bracketed arguments expected")
+fn replace_generics<'a>(it: impl Iterator<Item=&'a mut data::Types>, generics: &HashMap<String, data::StructTy>, new_structs: &mut HashMap<String, (data::StructTy, data::Types)>) {
+    for ty in it.filter_map(|ty| has_generic(ty)) {
+        let (name, inner, span) = match ty {
+            data::Types::Generic(name, inner, span) =>
+                (name.clone(), inner.clone(), span.clone()),
+            _ => unreachable!()
         };
-                if args.args.len() != 1 {
-                    emit_error(item.span(), "Expected 1 argument");
-                }
-                let ty = match &args.args[0] {
-                    syn::GenericArgument::Type(v) => parse_type(v),
-                    _ => emit_error(item.span(), "Type bracketed arguments expected")
+        let generic = match generics.get(&name) {
+            Some(v) => v,
+            None => emit_error(Some((span, "Type does not exists")))
         };
-                data::Types::Optional(ty.into())
-            } else {
-                parse_type_string(segment.ident.to_string())
-            }
-        }
-        syn::Type::Slice(slice) => {
-            data::Types::Array(parse_type(&slice.elem).into())
-        }
-        _ => emit_error(item.span(), "Unsupported type")
+        let new_name = format!("{}_{}", name, gen_generic_name(&inner));
+        *ty = data::Types::Named(new_name.clone());
+        new_structs.insert(new_name, (generic.clone(), *inner));
     }
 }
 
-fn parse_struct(item: &syn::ItemStruct) -> data::StructTy {
-    let name = item.ident.to_string();
-    let mut fields = vec![];
-    for field in &item.fields {
-        if field.ident.is_none() {
-            emit_error(field.span(), "Missing field name");
+fn replace_generic_type(ty: &mut data::Types, generic_name: &String, replacement: &data::Types) {
+    use data::Types;
+    match ty {
+        Types::Named(name) => if name == generic_name { *ty = replacement.clone(); } else { unreachable!() },
+        Types::Optional(inner) => replace_generic_type(inner, generic_name, replacement),
+        Types::Array(inner) => replace_generic_type(inner, generic_name, replacement),
+        _ => unreachable!()
     }
-        let name = field.ident.as_ref().unwrap().to_string();
-        let ty = parse_type(&field.ty);
-        fields.push(data::FieldTy { name, ty });
-    }
-    data::StructTy { name, fields }
 }
 
-fn try_parse_iterator(ty: &syn::Type) -> Option<data::Types> {
-    if let syn::Type::Path(ty) = ty {
-        let seg = ty.path.segments.last()?;
-        if seg.ident.to_string() == "Iterator" {
-            if let syn::PathArguments::AngleBracketed(args) = &seg.arguments {
-                if let Some(syn::GenericArgument::Type(ty)) = args.args.first() {
-                    Some(parse_type(ty))
-                } else { None }
-            } else { None }
-        } else { None }
-    } else { None }
+fn resolve_generics(rpc: &mut data::RPC) {
+    let mut generics: HashMap<String, data::StructTy> = HashMap::new();
+    rpc.structs.retain(|s| if s.generic_name.is_none() { true } else {
+        generics.insert(s.name.clone(), s.clone());
+        false
+    });
+
+    let mut new_structs = HashMap::new();
+    for s in &mut rpc.structs {
+        replace_generics(s.fields.iter_mut().map(|f| &mut f.ty), &generics, &mut new_structs);
+    }
+    for m in &mut rpc.services.iter_mut().map(|s| s.methods.iter_mut()).flatten() {
+        replace_generics(m.args.iter_mut().map(|f| &mut f.ty).chain(&mut m.ret), &generics, &mut new_structs);
     }
 
-fn parse_method(item: &syn::Signature) -> data::MethodTy {
-    let mut method = data::MethodTy::default();
-    method.name = item.ident.to_string();
-
-    for arg in &item.inputs {
-        let arg = match arg {
-            syn::FnArg::Typed(v) => v,
-            _ => emit_error(arg.span(), "Unsupported argument")
-        };
-        let ty = parse_type(&arg.ty);
-        let name = match &*arg.pat {
-            syn::Pat::Ident(v) => v.ident.to_string(),
-            _ => emit_error(arg.span(), "Unsupported argument")
-        };
-        method.args.push(data::FieldTy { name, ty });
+    for (name, (mut generic, inner)) in new_structs {
+        generic.name = name;
+        let generic_name = generic.generic_name.take().unwrap();
+        for mut field in generic.generic_fields {
+            replace_generic_type(&mut field.ty, &generic_name, &inner);
+            generic.fields.push(field);
         }
-
-    match &item.output {
-        syn::ReturnType::Default => {
-            method.ret = None;
-            method.ret_stream = false;
+        generic.generic_fields = vec![];
+        rpc.structs.push(generic);
     }
-        syn::ReturnType::Type(_, ty) => {
-            if let Some(ty) = try_parse_iterator(ty) {
-                method.ret_stream = true;
-                method.ret = Some(ty);
-            } else {
-                method.ret_stream = false;
-                method.ret = Some(parse_type(ty));
-            }
-        }
-    };
-
-    method
-}
-
-fn parse_service(item: &syn::ItemTrait) -> data::ServiceTy {
-    let name = item.ident.to_string();
-    let mut methods = vec![];
-    for item in &item.items {
-        let item = match item {
-            syn::TraitItem::Fn(v) => v,
-            _ => emit_error(item.span(), "Only functions are supported")
-        };
-        methods.push(parse_method(&item.sig));
-    }
-    data::ServiceTy { name, methods }
 }
 
 fn main() {
@@ -175,19 +129,21 @@ fn main() {
     SOURCE_FILE.set(args.file.to_string_lossy().to_string()).unwrap();
     SOURCE.set(content).unwrap();
 
-    let ast = syn::parse_file(SOURCE.get().unwrap()).unwrap();
+    let ast = match syn::parse_file(SOURCE.get().unwrap()) {
+        Ok(v) => v,
+        Err(e) => emit_error(e.into_iter()
+            .map(|e| {
+                let span = e.span();
+                let mut msg = String::new();
+                write!(msg, "{e}").unwrap();
+                (span, msg)
+            })
+        )
+    };
 
-    let mut rpc = data::RPC::default();
+    let mut rpc = parser::parse_file(&ast);
 
-    for item in &ast.items {
-        match item {
-            syn::Item::Enum(v) => rpc.enums.push(parse_enum(v)),
-            syn::Item::Struct(v) => rpc.structs.push(parse_struct(v)),
-            syn::Item::Trait(v) => rpc.services.push(parse_service(v)),
-            syn::Item::Use(_) => {}
-            _ => emit_error(item.span(), "Unsupported item")
-        }
-    }
+    resolve_generics(&mut rpc);
 
     for gen in &args.generators.clients {
         gen.generate(&args.rpc_name, &rpc);
@@ -198,7 +154,7 @@ fn main() {
     }
 }
 
-fn emit_error(span: proc_macro2::Span, msg: impl Into<String>) -> ! {
+pub fn emit_error(errors: impl IntoIterator<Item=(proc_macro2::Span, impl Into<String>)>) -> ! {
     use codespan_reporting::{
         diagnostic::{Diagnostic, Label},
         files::{SimpleFiles, Files},
@@ -214,14 +170,17 @@ fn emit_error(span: proc_macro2::Span, msg: impl Into<String>) -> ! {
 
     let file = files.get(file_id).unwrap();
 
+    let errors = errors.into_iter().map(|(span, msg)| {
         let start = span.start();
         let start: usize = file.line_range((), start.line-1).unwrap().start + start.column;
         let end = span.end();
         let end: usize = file.line_range((), end.line-1).unwrap().start + end.column;
+        Label::primary(file_id, start..end).with_message(msg)
+    });
 
     let diagnostic = Diagnostic::error()
-        .with_labels(vec![Label::primary(file_id, start..end).with_message(msg)]);
+        .with_labels(errors.collect());
 
     term::emit(&mut writer.lock(), &config, &files, &diagnostic).expect("cannot write error");
-    std::process::abort();
+    std::process::exit(1);
 }

src/parser.rs

@@ -0,0 +1,200 @@
+use syn::spanned::Spanned;
+use super::{data, emit_error};
+
+fn parse_enum(item: &syn::ItemEnum) -> data::EnumTy {
+    data::EnumTy {
+        name: item.ident.to_string(),
+        values: item.variants.iter().enumerate().map(|(i, v) | (v.ident.to_string(), i)).collect()
+    }
+}
+
+fn parse_type_string(ty: String) -> data::Types {
+    use data::Types::*;
+    match ty.as_str() {
+        "str" | "String" => String,
+        "bool" => Bool,
+        "f32" => F32,
+        "f64" => F64,
+        "i8" => I8,
+        "i16" => I16,
+        "i32" => I32,
+        "i64" => I64,
+        "u8" => U8,
+        "u16" => U16,
+        "u32" => U32,
+        "u64" => U64,
+        _ => Named(ty)
+    }
+}
+
+fn parse_type(item: &syn::Type) -> data::Types {
+    match item {
+        syn::Type::Path(path) => {
+            let segments = &path.path.segments;
+            if segments.len() != 1 {
+                emit_error(vec![(item.span(), "Path segments with len != 1")]);
+            }
+            let segment = &segments[0];
+            if !segment.arguments.is_empty() {
+                let args = match &segment.arguments {
+                    syn::PathArguments::AngleBracketed(v) => v,
+                    _ => emit_error(vec![(item.span(), "Angle bracketed arguments expected")])
+                };
+                if args.args.len() != 1 {
+                    emit_error(vec![(item.span(), "Expected 1 argument")]);
+                }
+                let ty = match &args.args[0] {
+                    syn::GenericArgument::Type(v) => parse_type(v),
+                    _ => emit_error(vec![(item.span(), "Only types are supported")])
+                };
+                let name = segment.ident.to_string();
+                if name == "Option" {
+                    data::Types::Optional(ty.into())
+                } else if name == "Vec" {
+                    data::Types::Array(ty.into())
+                } else {
+                    data::Types::Generic(name, ty.into(), segment.ident.span())
+                }
+            } else {
+                parse_type_string(segment.ident.to_string())
+            }
+        }
+        syn::Type::Slice(slice) => {
+            data::Types::Array(parse_type(&slice.elem).into())
+        }
+        _ => emit_error(vec![(item.span(), "Unsupported type")])
+    }
+}
+
+fn has_generic(ty: &data::Types, generic: &String) -> bool {
+    use data::Types;
+    match ty {
+        Types::String | Types::Bool |
+        Types::F32 | Types::F64 |
+        Types::I8 | Types::I16 | Types::I32 | Types::I64 |
+        Types::U8 | Types::U16 | Types::U32 | Types::U64 => false,
+        Types::Array(inner) => has_generic(inner, generic),
+        Types::Optional(inner) => has_generic(inner, generic),
+        Types::Named(name) => name == generic,
+        Types::Generic(name, inner, _) => name == generic || has_generic(inner, generic)
+    }
+}
+
+fn parse_struct(item: &syn::ItemStruct) -> data::StructTy {
+    let name = item.ident.to_string();
+    if let Some(v) = &item.generics.where_clause {
+        emit_error(Some((v.span(), "Where clauses are not allowed")));
+    }
+    if item.generics.params.len() > 1 {
+        emit_error(Some((item.generics.params.span(), "Only one generic parameter is allowed for now")));
+    }
+    let generic_name = item.generics.params.first().map(|g| {
+        match g {
+            syn::GenericParam::Const(_) |
+            syn::GenericParam::Lifetime(_) => emit_error(Some((g.span(), "Only generic types are allowed"))),
+            syn::GenericParam::Type(ty) => {
+                if !ty.bounds.is_empty() {
+                    emit_error(Some((ty.span(), "Bounds are not allowed")));
+                }
+                if let Some(d) = &ty.default {
+                    emit_error(Some((d.span(), "Defaults are not allowed")));
+                }
+                ty.ident.to_string()
+            }
+        }
+    });
+    let mut generic_fields = vec![];
+    let mut fields = vec![];
+    for field in &item.fields {
+        if field.ident.is_none() {
+            emit_error(vec![(field.span(), "Missing field name")]);
+        }
+        let name = field.ident.as_ref().unwrap().to_string();
+        let ty = parse_type(&field.ty);
+        let ty = data::FieldTy { name, ty };
+        if generic_name.is_some() && has_generic(&ty.ty, generic_name.as_ref().unwrap()) {
+            generic_fields.push(ty);
+        } else {
+            fields.push(ty);
+        }
+    }
+    data::StructTy { name, fields, generic_fields, generic_name }
+}
+
+fn try_parse_iterator(ty: &syn::Type) -> Option<data::Types> {
+    if let syn::Type::Path(ty) = ty {
+        let seg = ty.path.segments.last()?;
+        if seg.ident.to_string() == "Iterator" {
+            if let syn::PathArguments::AngleBracketed(args) = &seg.arguments {
+                if let Some(syn::GenericArgument::Type(ty)) = args.args.first() {
+                    Some(parse_type(ty))
+                } else { None }
+            } else { None }
+        } else { None }
+    } else { None }
+}
+
+fn parse_method(item: &syn::Signature) -> data::MethodTy {
+    let mut method = data::MethodTy::default();
+    method.name = item.ident.to_string();
+
+    for arg in &item.inputs {
+        let arg = match arg {
+            syn::FnArg::Typed(v) => v,
+            _ => emit_error(vec![(arg.span(), "Unsupported argument")])
+        };
+        let ty = parse_type(&arg.ty);
+        let name = match &*arg.pat {
+            syn::Pat::Ident(v) => v.ident.to_string(),
+            _ => emit_error(vec![(arg.span(), "Unsupported argument")])
+        };
+        method.args.push(data::FieldTy { name, ty });
+    }
+
+    match &item.output {
+        syn::ReturnType::Default => {
+            method.ret = None;
+            method.ret_stream = false;
+        }
+        syn::ReturnType::Type(_, ty) => {
+            if let Some(ty) = try_parse_iterator(ty) {
+                method.ret_stream = true;
+                method.ret = Some(ty);
+            } else {
+                method.ret_stream = false;
+                method.ret = Some(parse_type(ty));
+            }
+        }
+    };
+
+    method
+}
+
+fn parse_service(item: &syn::ItemTrait) -> data::ServiceTy {
+    let name = item.ident.to_string();
+    let mut methods = vec![];
+    for item in &item.items {
+        let item = match item {
+            syn::TraitItem::Fn(v) => v,
+            _ => emit_error(vec![(item.span(), "Only functions are supported")])
+        };
+        methods.push(parse_method(&item.sig));
+    }
+    data::ServiceTy { name, methods }
+}
+
+pub fn parse_file(ast: &syn::File) -> data::RPC {
+    let mut rpc = data::RPC::default();
+
+    for item in &ast.items {
+        match item {
+            syn::Item::Enum(v) => rpc.enums.push(parse_enum(v)),
+            syn::Item::Struct(v) => rpc.structs.push(parse_struct(v)),
+            syn::Item::Trait(v) => rpc.services.push(parse_service(v)),
+            syn::Item::Use(_) => {}
+            _ => emit_error(vec![(item.span(), "Unsupported item")])
+        }
+    }
+
+    rpc
+}

templates/typescript_client.rs.ts

@@ -18,17 +18,17 @@ export interface @s.name @{
 export class MRPCConnector @{
     url: string;
 
+    private __create_msg(service: string, method: string, data: any) @{
+        return @{service, method, data@};
+    @}
+
     public constructor(url: string) @{
         this.url = url;
     @}
 
 @for s in &rpc.services { @for m in &s.methods {
     public @(s.name)_@(m.name)(@method_args(m))@method_ret(m) @{
-        const __msg = @{
-            service: '@s.name',
-            method: '@m.name',
-            data: @{@m.args.iter().map(|a| &a.name).join(",")@}
-        @};
+        const __msg = this.__create_msg('@s.name', '@m.name', @{@m.args.iter().map(|a| &a.name).join(",")@});
         @if m.ret.is_some() && !m.ret_stream {return fetch(this.url, @{
             method: 'POST',
             body: JSON.stringify(__msg)