fix(go): prevent GC finalizer on borrowed resource handles

FromBorrowHandle for imported resources was incorrectly delegating to
FromOwnHandle, which registers a GC finalizer via runtime.AddCleanup.
This violates the Component Model specification: borrowed handles are
not owned by the callee, so the callee must not drop them. When Go's
garbage collector ran, it would drop borrowed handles through the
finalizer, corrupting the host's resource table.

Fix FromBorrowHandle to create a handle object directly without
registering a GC finalizer, preserving the correct ownership semantics.

Author: sumleo

Cargo.lock

@@ -119,9 +119,3 @@ csharp = ['dep:wit-bindgen-csharp']
 csharp-mono = ['csharp']
 moonbit = ['dep:wit-bindgen-moonbit']
 async = []
-
-[dev-dependencies]
-wit-bindgen-core = { workspace = true }
-wit-bindgen-rust = { workspace = true }
-wit-bindgen-go = { workspace = true }
-wit-parser = { workspace = true }

Cargo.toml

@@ -2589,7 +2589,8 @@ func {camel}FromOwnHandle(handleValue int32) *{camel} {{
 }}
 
 func {camel}FromBorrowHandle(handleValue int32) *{camel} {{
-	return {camel}FromOwnHandle(handleValue)
+	handle := wit_runtime.MakeHandle(handleValue)
+	return &{camel}{{handle}}
 }}
 "#
             );

crates/go/src/lib.rs

@@ -0,0 +1,20 @@
+package export_wit_world
+
+import (
+	"fmt"
+	test "wit_component/test_resource_borrow_to_test"
+)
+
+func Run() {
+	thing := test.MakeThing(42)
+	defer thing.Drop()
+
+	result := test.Foo(thing)
+	assertEqual(result, uint32(42+1+2))
+}
+
+func assertEqual[T comparable](a T, b T) {
+	if a != b {
+		panic(fmt.Sprintf("%v not equal to %v", a, b))
+	}
+}

tests/runtime/resource-borrow/runner.go

@@ -0,0 +1,21 @@
+package export_test_resource_borrow_to_test
+
+import (
+	"runtime"
+)
+
+type Thing struct {
+	pinner runtime.Pinner
+	handle int32
+	val    uint32
+}
+
+func (self *Thing) OnDrop() {}
+
+func MakeThing(v uint32) *Thing {
+	return &Thing{runtime.Pinner{}, 0, v + 1}
+}
+
+func Foo(v *Thing) uint32 {
+	return v.val + 2
+}