feat(go-bindgen): flatten result tuples

Cargo.toml

@@ -131,7 +131,7 @@ wasmtime-wasi = { version = "25", default-features = false }
 wit-bindgen = { version = "0.30", default-features = false }
 wit-bindgen-core = { version = "0.30", default-features = false }
 wit-bindgen-wrpc = { version = "0.6.5", default-features = false, path = "./crates/wit-bindgen" }
-wit-bindgen-wrpc-go = { version = "0.8.1", default-features = false, path = "./crates/wit-bindgen-go" }
+wit-bindgen-wrpc-go = { version = "0.9", default-features = false, path = "./crates/wit-bindgen-go" }
 wit-bindgen-wrpc-rust = { version = "0.6.5", default-features = false, path = "./crates/wit-bindgen-rust" }
 wit-bindgen-wrpc-rust-macro = { version = "0.6.5", default-features = false, path = "./crates/wit-bindgen-rust-macro" }
 wit-component = { version = "0.217", default-features = false }

crates/wit-bindgen-go/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "wit-bindgen-wrpc-go"
-version = "0.8.1"
+version = "0.9.0"
 description = """
 Go bindings generator for wRPC
 """

crates/wit-bindgen-go/src/interface.rs

@@ -1,3 +1,5 @@
+use core::iter;
+
 use std::fmt::Write as _;
 use std::mem;
 
@@ -49,6 +51,26 @@ fn go_func_name(func: &Function) -> String {
     }
 }
 
+pub fn flatten_ty<'a>(resolve: &'a Resolve, ty: &Type) -> impl Iterator<Item = Type> + 'a {
+    let mut ty = *ty;
+    loop {
+        if let Type::Id(id) = ty {
+            match resolve.types[id].kind {
+                TypeDefKind::Type(t) => {
+                    ty = t;
+                    continue;
+                }
+                TypeDefKind::Tuple(ref t) => {
+                    return Box::new(t.types.iter().flat_map(|ty| flatten_ty(resolve, ty)))
+                        as Box<dyn Iterator<Item = Type>>
+                }
+                _ => {}
+            }
+        }
+        return Box::new(iter::once(ty)) as Box<dyn Iterator<Item = Type>>;
+    }
+}
+
 pub struct InterfaceGenerator<'a> {
     pub src: Source,
     pub(super) identifier: Identifier<'a>,
@@ -2401,8 +2423,12 @@ impl InterfaceGenerator<'_> {
             let prev = mem::take(&mut self.src);
             self.print_docs_and_params(func);
             self.src.push_str(" (");
-            for ty in func.results.iter_types() {
-                self.print_opt_ty(ty, true);
+            for ty in func
+                .results
+                .iter_types()
+                .flat_map(|ty| flatten_ty(self.resolve, ty))
+            {
+                self.print_opt_ty(&ty, true);
                 self.src.push_str(", ");
             }
             self.push_str("error)\n");
@@ -2508,11 +2534,16 @@ func ServeInterface(s {wrpc}.Server, h Handler) (stop func() error, err error) {
                 r#"
         {slog}.DebugContext(ctx, "calling `{instance}.{name}` handler")"#,
             );
-            for (i, _) in func.results.iter_types().enumerate() {
+            let results: Box<[Type]> = func
+                .results
+                .iter_types()
+                .flat_map(|ty| flatten_ty(self.resolve, ty))
+                .collect();
+            for (i, _) in results.iter().enumerate() {
                 uwrite!(self.src, "r{i}, ");
             }
             self.push_str("err ");
-            if func.results.len() > 0 {
+            if results.len() > 0 {
                 self.push_str(":");
             }
             self.push_str("= h.");
@@ -2534,9 +2565,9 @@ func ServeInterface(s {wrpc}.Server, h Handler) (stop func() error, err error) {
 
         var buf {bytes}.Buffer
         writes := make(map[uint32]func({wrpc}.IndexWriter) error, {})"#,
-                func.results.len()
+                results.len()
             );
-            for (i, ty) in func.results.iter_types().enumerate() {
+            for (i, ty) in results.iter().enumerate() {
                 uwrite!(
                     self.src,
                     r#"
@@ -2632,7 +2663,12 @@ func ServeInterface(s {wrpc}.Server, h Handler) (stop func() error, err error) {
             self.print_docs_and_params(func);
 
             self.src.push_str(" (");
-            for (i, ty) in func.results.iter_types().enumerate() {
+            let results: Box<[Type]> = func
+                .results
+                .iter_types()
+                .flat_map(|ty| flatten_ty(self.resolve, ty))
+                .collect();
+            for (i, ty) in results.iter().enumerate() {
                 uwrite!(self.src, "r{i}__ ");
                 self.print_opt_ty(ty, true);
                 self.src.push_str(", ");
@@ -2735,7 +2771,7 @@ func ServeInterface(s {wrpc}.Server, h Handler) (stop func() error, err error) {
                 self.src.push_str("nil");
             }
             self.src.push_str(",\n");
-            for (i, ty) in func.results.iter_types().enumerate() {
+            for (i, ty) in results.iter().enumerate() {
                 let (nested, fut) = async_paths_ty(self.resolve, ty);
                 for path in nested {
                     uwrite!(self.src, "{wrpc}.NewSubscribePath().Index({i})");
@@ -2812,7 +2848,7 @@ func ServeInterface(s {wrpc}.Server, h Handler) (stop func() error, err error) {
                 func.name,
             );
 
-            for (i, ty) in func.results.iter_types().enumerate() {
+            for (i, ty) in results.iter().enumerate() {
                 uwrite!(
                     self.src,
                     "

examples/go/hello-client/bindings/client.wrpc.go

@@ -1,3 +1,3 @@
-// Generated by `wit-bindgen-wrpc-go` 0.8.1. DO NOT EDIT!
+// Generated by `wit-bindgen-wrpc-go` 0.9.0. DO NOT EDIT!
 // client package contains wRPC bindings for `client` world
 package client

examples/go/hello-client/bindings/wrpc_examples/hello/handler/bindings.wrpc.go

@@ -1,4 +1,4 @@
-// Generated by `wit-bindgen-wrpc-go` 0.8.1. DO NOT EDIT!
+// Generated by `wit-bindgen-wrpc-go` 0.9.0. DO NOT EDIT!
 package handler
 
 import (

examples/go/hello-server/bindings/exports/wrpc_examples/hello/handler/bindings.wrpc.go

@@ -1,4 +1,4 @@
-// Generated by `wit-bindgen-wrpc-go` 0.8.1. DO NOT EDIT!
+// Generated by `wit-bindgen-wrpc-go` 0.9.0. DO NOT EDIT!
 package handler
 
 import (

examples/go/hello-server/bindings/server.wrpc.go

@@ -1,4 +1,4 @@
-// Generated by `wit-bindgen-wrpc-go` 0.8.1. DO NOT EDIT!
+// Generated by `wit-bindgen-wrpc-go` 0.9.0. DO NOT EDIT!
 // server package contains wRPC bindings for `server` world
 package server
 

examples/go/resources-server/bindings/exports/wrpc_examples/resources/resources/bindings.wrpc.go

@@ -1,4 +1,4 @@
-// Generated by `wit-bindgen-wrpc-go` 0.8.1. DO NOT EDIT!
+// Generated by `wit-bindgen-wrpc-go` 0.9.0. DO NOT EDIT!
 package resources
 
 import (

examples/go/resources-server/bindings/server.wrpc.go

@@ -1,4 +1,4 @@
-// Generated by `wit-bindgen-wrpc-go` 0.8.1. DO NOT EDIT!
+// Generated by `wit-bindgen-wrpc-go` 0.9.0. DO NOT EDIT!
 // server package contains wRPC bindings for `server` world
 package server
 

examples/go/streams-client/bindings/client.wrpc.go

@@ -1,3 +1,3 @@
-// Generated by `wit-bindgen-wrpc-go` 0.8.1. DO NOT EDIT!
+// Generated by `wit-bindgen-wrpc-go` 0.9.0. DO NOT EDIT!
 // client package contains wRPC bindings for `client` world
 package client

examples/go/streams-client/bindings/wrpc_examples/streams/handler/bindings.wrpc.go

@@ -1,4 +1,4 @@
-// Generated by `wit-bindgen-wrpc-go` 0.8.1. DO NOT EDIT!
+// Generated by `wit-bindgen-wrpc-go` 0.9.0. DO NOT EDIT!
 package handler
 
 import (

examples/go/streams-server/bindings/exports/wrpc_examples/streams/handler/bindings.wrpc.go

@@ -1,4 +1,4 @@
-// Generated by `wit-bindgen-wrpc-go` 0.8.1. DO NOT EDIT!
+// Generated by `wit-bindgen-wrpc-go` 0.9.0. DO NOT EDIT!
 package handler
 
 import (

examples/go/streams-server/bindings/server.wrpc.go

@@ -1,4 +1,4 @@
-// Generated by `wit-bindgen-wrpc-go` 0.8.1. DO NOT EDIT!
+// Generated by `wit-bindgen-wrpc-go` 0.9.0. DO NOT EDIT!
 // server package contains wRPC bindings for `server` world
 package server
 

examples/go/wasi-keyvalue-client/bindings/client.wrpc.go

@@ -1,3 +1,3 @@
-// Generated by `wit-bindgen-wrpc-go` 0.8.1. DO NOT EDIT!
+// Generated by `wit-bindgen-wrpc-go` 0.9.0. DO NOT EDIT!
 // client package contains wRPC bindings for `client` world
 package client

examples/go/wasi-keyvalue-client/bindings/wasi/keyvalue/store/bindings.wrpc.go

@@ -1,4 +1,4 @@
-// Generated by `wit-bindgen-wrpc-go` 0.8.1. DO NOT EDIT!
+// Generated by `wit-bindgen-wrpc-go` 0.9.0. DO NOT EDIT!
 package store
 
 import (

examples/go/wasi-keyvalue-server/bindings/exports/wasi/keyvalue/store/bindings.wrpc.go

@@ -1,4 +1,4 @@
-// Generated by `wit-bindgen-wrpc-go` 0.8.1. DO NOT EDIT!
+// Generated by `wit-bindgen-wrpc-go` 0.9.0. DO NOT EDIT!
 package store
 
 import (

examples/go/wasi-keyvalue-server/bindings/server.wrpc.go

@@ -1,4 +1,4 @@
-// Generated by `wit-bindgen-wrpc-go` 0.8.1. DO NOT EDIT!
+// Generated by `wit-bindgen-wrpc-go` 0.9.0. DO NOT EDIT!
 // server package contains wRPC bindings for `server` world
 package server
 

tests/go/sync.go

@@ -38,10 +38,8 @@ func (SyncHandler) Fallible(ctx context.Context, ok bool) (*wrpc.Result[bool, st
 	}
 }
 
-func (SyncHandler) Numbers(ctx context.Context) (*wrpc.Tuple10[uint8, uint16, uint32, uint64, int8, int16, int32, int64, float32, float64], error) {
-	return &wrpc.Tuple10[uint8, uint16, uint32, uint64, int8, int16, int32, int64, float32, float64]{
-		V0: 1, V1: 2, V2: 3, V3: 4, V4: 5, V5: 6, V6: 7, V7: 8, V8: 9, V9: 10,
-	}, nil
+func (SyncHandler) Numbers(ctx context.Context) (uint8, uint16, uint32, uint64, int8, int16, int32, int64, float32, float64, error) {
+	return 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, nil
 }
 
 func (SyncHandler) WithFlags(ctx context.Context, a, b, c bool) (*sync.Abc, error) {
@@ -106,20 +104,19 @@ func (SyncHandler) WithRecordList(ctx context.Context, n uint8) ([]*sync.Rec, er
 	return vs, nil
 }
 
-func (SyncHandler) WithRecordTuple(ctx context.Context) (*wrpc.Tuple2[*sync.Rec, *sync.Rec], error) {
+func (SyncHandler) WithRecordTuple(ctx context.Context) (*sync.Rec, *sync.Rec, error) {
 	slog.DebugContext(ctx, "handling `with-record-tuple`")
-	return &wrpc.Tuple2[*sync.Rec, *sync.Rec]{
-		V0: &sync.Rec{
+	return &sync.Rec{
 			Nested: &sync.RecNested{
 				Foo: "0",
 			},
 		},
-		V1: &sync.Rec{
+		&sync.Rec{
 			Nested: &sync.RecNested{
 				Foo: "1",
 			},
 		},
-	}, nil
+		nil
 }
 
 func (SyncHandler) WithEnum(ctx context.Context) (sync.Foobar, error) {

tests/go/sync_test.go

@@ -100,14 +100,49 @@ func TestSync(t *testing.T) {
 	}
 	{
 		slog.DebugContext(ctx, "calling `wrpc-test:integration/sync.numbers`")
-		v, err := sync.Numbers(ctx, client)
+		v0, v1, v2, v3, v4, v5, v6, v7, v8, v9, err := sync.Numbers(ctx, client)
 		if err != nil {
 			t.Errorf("failed to call `wrpc-test:integration/sync.numbers`: %s", err)
 			return
 		}
-		expected := &wrpc.Tuple10[uint8, uint16, uint32, uint64, int8, int16, int32, int64, float32, float64]{V0: 1, V1: 2, V2: 3, V3: 4, V4: 5, V5: 6, V6: 7, V7: 8, V8: 9, V9: 10}
-		if !reflect.DeepEqual(v, expected) {
-			t.Errorf("expected: %v, got: %#v", expected, v)
+		if v0 != 1 {
+			t.Errorf("expected: 1, got: %#v", v0)
+			return
+		}
+		if v1 != 2 {
+			t.Errorf("expected: 2, got: %#v", v1)
+			return
+		}
+		if v2 != 3 {
+			t.Errorf("expected: 3, got: %#v", v2)
+			return
+		}
+		if v3 != 4 {
+			t.Errorf("expected: 4, got: %#v", v3)
+			return
+		}
+		if v4 != 5 {
+			t.Errorf("expected: 5, got: %#v", v4)
+			return
+		}
+		if v5 != 6 {
+			t.Errorf("expected: 6, got: %#v", v5)
+			return
+		}
+		if v6 != 7 {
+			t.Errorf("expected: 7, got: %#v", v6)
+			return
+		}
+		if v7 != 8 {
+			t.Errorf("expected: 8, got: %#v", v7)
+			return
+		}
+		if v8 != 9 {
+			t.Errorf("expected: 9, got: %#v", v8)
+			return
+		}
+		if v9 != 10 {
+			t.Errorf("expected: 10, got: %#v", v9)
 			return
 		}
 	}

tests/wit/test.wit

@@ -37,7 +37,7 @@ interface sync {
 }
 
 interface async {
-    with-streams: func(complete: bool) -> (bytes: stream<u8>, lists: stream<list<string>>);
+    with-streams: func(complete: bool) -> tuple<stream<u8>, stream<list<string>>>;
 }
 
 interface resources {