Device macro to generate stateful and publish variants of device specific poll inputs.

Cargo.toml

@@ -10,6 +10,8 @@ members = [
     "peripherals/standalone-ads1256/*",
     # Peripheral components
     "peripheral-components/ads1256/*",
+    # Macros
+    "macros/node-poll-variants",
     # Examples
     "examples/ads1256"
 ]
@@ -87,6 +89,14 @@ features = ["defmt", "unstable-traits", "unstable-pac", "nightly"]
 [workspace.dependencies.embassy-nrf]
 version = "0.1.*"
 features = ["defmt", "unstable-traits", "nightly"]
+# Macros
+[workspace.dependencies.syn]
+version = "2.0.*"
+features = ["extra-traits"]
+[workspace.dependencies.quote]
+version = "1.0.*"
+[workspace.dependencies.trybuild]
+version = "1.0.*"
 
 #---------------------------------------------------------------------------------------------------------------------
 #----- Patch ------------------------

macros/node-poll-variants/Cargo.toml

@@ -0,0 +1,23 @@
+[package]
+name = "node-poll-variants"
+description = "Macros for physical nodes."
+version.workspace = true
+edition.workspace = true
+repository.workspace = true
+readme.workspace = true
+license.workspace = true
+
+[lib]
+proc-macro = true
+
+[[test]]
+name = "tests"
+path = "tests/test_build.rs"
+
+[dependencies.syn]
+workspace = true
+[dependencies.quote]
+workspace = true
+
+[dev-dependencies.trybuild]
+workspace = true

macros/node-poll-variants/src/lib.rs

@@ -0,0 +1,46 @@
+use proc_macro::TokenStream;
+use std::ops::Deref;
+use quote::quote;
+use syn::{parse_macro_input, DeriveInput, Data, Ident};
+
+// Struct name: Ads1256PollStateful, Ads1256PollPublish, Ads1256PollStatePub
+#[proc_macro_derive(PollVariants)]
+pub fn transducer_macro(input: TokenStream) -> TokenStream {
+    let input = parse_macro_input!(input as DeriveInput);
+    let DeriveInput {
+        attrs,
+        vis,
+        ident,
+        generics,
+        data,
+    } = &input;
+    // Check that item the macro was used on is valid
+    match data {
+        Data::Struct(struct_data) => struct_data,
+        Data::Enum(_) => panic!("Stateful struct cannot be derived from an enum."),
+        Data::Union(_) => panic!("Stateful struct cannot be derived from a union.")
+    };
+    // Check if generics contains T
+
+    // If it does make sure it is T: Copy
+    // If it isn't Copy, panic
+
+    // If it doesn't contain T, add it for use in the type that will be generated
+
+    let (impl_generics, ty_generics, where_clause) = generics.split_for_impl();
+
+    let stateful_name = format!("{ident}Stateful");
+    let stateful_ident = Ident::new(stateful_name.deref(), ident.span());
+
+    eprintln!("input: {input:#?}");
+    eprintln!("impl_generics: {impl_generics:#?}");
+
+    let expanded = quote! {
+        #vis struct #stateful_ident #generics {
+            pub poll: #ident #ty_generics,
+            pub state: physical::transducer::State<T>,
+        }
+    };
+
+    TokenStream::from(expanded)
+}

macros/node-poll-variants/tests/generate.rs

@@ -0,0 +1,11 @@
+use node_poll_variants::{PollVariants};
+
+#[derive(PollVariants)]
+struct ExamplePoll<'a, FirstT: Copy, SecondT> {
+    a: &'a i32,
+    b: i32,
+    first: FirstT,
+    second: SecondT,
+}
+
+fn main() {}

macros/node-poll-variants/tests/test_build.rs

@@ -0,0 +1,5 @@
+#[test]
+fn tests() {
+    let t = trybuild::TestCases::new();
+    t.pass("tests/generate.rs");
+}

src/transducer/output.rs

@@ -1,7 +1,9 @@
 pub trait Output {
     type Value: Copy;
 
-    //TODO: return result
-    //TODO: Make maybe async
-    fn output(&mut self, setting: Self::Value);
-}
+    //TODO: Should this be maybe async?
+    fn output(&mut self, setting: Self::Value) -> Result<(), InvalidOutputSetting>;
+}
+
+/// Indicates the setting given for an [Output] is statically known to be an impossible setting to achieve.
+pub struct InvalidOutputSetting;