add serde big array support (fixed #327) (#328)

* add serde big array support

Author: fawdlstty

rosidl_generator_rs/resource/Cargo.toml.em

@@ -6,13 +6,14 @@ edition = "2021"
 [dependencies]
 rosidl_runtime_rs = "0.3"
 serde = { version = "1", optional = true, features = ["derive"] }
+serde-big-array = { version = "0.5.1", optional = true }
 @[for dep in dependency_packages]@
 @(dep) = "*"
 @[end for]@
 
 [features]
 @{
-serde_features = ["dep:serde", "rosidl_runtime_rs/serde"]
+serde_features = ["dep:serde", "dep:serde-big-array", "rosidl_runtime_rs/serde"]
 for dep in dependency_packages:
 	serde_features.append("{}/serde".format(dep))
 }@

rosidl_generator_rs/resource/msg.rs.em

@@ -5,6 +5,7 @@ TEMPLATE(
     package_name=package_name, interface_path=interface_path,
     msg_specs=msg_specs,
     get_rs_name=get_rs_name, get_rmw_rs_type=get_rmw_rs_type,
+    pre_field_serde=pre_field_serde,
     get_idiomatic_rs_type=get_idiomatic_rs_type,
     constant_value_to_rs=constant_value_to_rs)
 }@
@@ -16,6 +17,7 @@ TEMPLATE(
     package_name=package_name, interface_path=interface_path,
     msg_specs=msg_specs,
     get_rs_name=get_rs_name, get_rmw_rs_type=get_rmw_rs_type,
+    pre_field_serde=pre_field_serde,
     get_idiomatic_rs_type=get_idiomatic_rs_type,
     constant_value_to_rs=constant_value_to_rs)
 }@

rosidl_generator_rs/resource/msg_idiomatic.rs.em

@@ -26,7 +26,7 @@ type_name = msg_spec.structure.namespaced_type.name
 #[derive(Clone, Debug, PartialEq, PartialOrd)]
 pub struct @(type_name) {
 @[for member in msg_spec.structure.members]@
-    pub @(get_rs_name(member.name)): @(get_idiomatic_rs_type(member.type)),
+    @(pre_field_serde(member.type))pub @(get_rs_name(member.name)): @(get_idiomatic_rs_type(member.type)),
 @[end for]@
 }
 

rosidl_generator_rs/resource/msg_rmw.rs.em

@@ -38,7 +38,7 @@ extern "C" {
 #[derive(Clone, Debug, PartialEq, PartialOrd)]
 pub struct @(type_name) {
 @[for member in msg_spec.structure.members]@
-    pub @(get_rs_name(member.name)): @(get_rmw_rs_type(member.type)),
+    @(pre_field_serde(member.type))pub @(get_rs_name(member.name)): @(get_rmw_rs_type(member.type)),
 @[end for]@
 }
 

rosidl_generator_rs/resource/srv.rs.em

@@ -12,6 +12,7 @@ TEMPLATE(
     package_name=package_name, interface_path=interface_path,
     msg_specs=req_res_specs,
     get_rs_name=get_rs_name, get_rmw_rs_type=get_rmw_rs_type,
+    pre_field_serde=pre_field_serde,
     get_idiomatic_rs_type=get_idiomatic_rs_type,
     constant_value_to_rs=constant_value_to_rs)
 }@
@@ -49,6 +50,7 @@ TEMPLATE(
     package_name=package_name, interface_path=interface_path,
     msg_specs=req_res_specs,
     get_rs_name=get_rs_name, get_rmw_rs_type=get_rmw_rs_type,
+    pre_field_serde=pre_field_serde,
     get_idiomatic_rs_type=get_idiomatic_rs_type,
     constant_value_to_rs=constant_value_to_rs)
 }@

rosidl_generator_rs/rosidl_generator_rs/__init__.py

@@ -101,6 +101,7 @@ def generate_rs(generator_arguments_file, typesupport_impls):
             'Services template file %s not found' % template_file
 
     data = {
+        'pre_field_serde': pre_field_serde,
         'get_rmw_rs_type': make_get_rmw_rs_type(args['package_name']),
         'get_rs_name': get_rs_name,
         'get_idiomatic_rs_type': make_get_idiomatic_rs_type(args['package_name']),
@@ -274,6 +275,14 @@ def constant_value_to_rs(type_, value):
 #     - BoundedSequence
 #     - UnboundedSequence
 
+
+def pre_field_serde(type_):
+    if isinstance(type_, Array) and type_.size > 32:
+        return '#[cfg_attr(feature = "serde", serde(with = "serde_big_array::BigArray"))]\n    '
+    else:
+        return ''
+
+
 def make_get_idiomatic_rs_type(package_name):
     get_rmw_rs_type = make_get_rmw_rs_type(package_name)
     def get_idiomatic_rs_type(type_):