feat(mavlink): adopt the kaptan-native dialect

firmware/libs/kaptan-mavlink/build.rs

@@ -2,26 +2,29 @@ use std::path::PathBuf;
 
 fn main() {
     let manifest_directory = PathBuf::from(std::env::var("CARGO_MANIFEST_DIR").unwrap());
-    let dialect = manifest_directory.join("definitions/kaptan.xml");
-    let config = manifest_directory.join("definitions/kaptan/config.xml");
-    let log = manifest_directory.join("definitions/kaptan/log.xml");
-    let error = manifest_directory.join("definitions/kaptan/error.xml");
-    for definition in [&dialect, &config, &log, &error] {
-        println!("cargo::rerun-if-changed={}", definition.display());
-    }
-    println!("cargo::rustc-check-cfg=cfg(kaptan_has_messages)");
+    let definitions = manifest_directory.join("definitions");
+    let dialect = definitions.join("kaptan.xml");
+    println!("cargo::rerun-if-changed={}", definitions.display());
     // The upstream generator conditionally emits derives for these optional
     // ecosystem crates. Kaptan deliberately does not expose those incomplete
     // features, so tell rustc the generated inactive cfgs are intentional.
     println!("cargo::rustc-check-cfg=cfg(feature, values(\"serde\", \"arbitrary\", \"ts-rs\"))");
-    if std::env::var_os("CARGO_FEATURE_DIALECT_KAPTAN").is_some() {
-        let output_directory = std::env::var("OUT_DIR").unwrap();
-        let generated = mavlink_bindgen::generate(
-            mavlink_bindgen::XmlDefinitions::Files(vec![dialect]),
-            output_directory,
-        )
-        .unwrap();
-        mavlink_bindgen::emit_cargo_build_messages(&generated);
-        println!("cargo::rustc-cfg=kaptan_has_messages");
-    }
+    let output_directory = std::env::var("OUT_DIR").unwrap();
+    mavlink_bindgen::generate(
+        mavlink_bindgen::XmlDefinitions::Files(vec![dialect]),
+        &output_directory,
+    )
+    .unwrap();
+    // Bindgen's index feature-gates every dialect module. Kaptan has exactly
+    // one unconditional dialect, so load its generated file as a normal Rust
+    // module instead of exposing a redundant Cargo feature.
+    std::fs::write(
+        PathBuf::from(output_directory).join("kaptan_module.rs"),
+        "#[allow(non_camel_case_types, non_snake_case)]\n\
+         #[allow(clippy::derive_partial_eq_without_eq, clippy::field_reassign_with_default)]\n\
+         #[allow(clippy::unnecessary_cast, clippy::bad_bit_mask)]\n\
+         #[allow(clippy::suspicious_else_formatting)]\n\
+         #[path = \"kaptan.rs\"]\npub mod kaptan;\n",
+    )
+    .unwrap();
 }