refactor: Move definition writing into separate function

config.lua

@@ -744,6 +744,7 @@ device_manager:schedule("0 0 20 * * *", function()
 	bedroom_air_filter:set_on(false)
 end)
 
+---@type Config
 return {
 	fulfillment = {
 		openid_url = "https://login.huizinga.dev/api/oidc",

src/bin/generate_definitions.rs

@@ -6,23 +6,33 @@ use tracing::{info, warn};
 
 extern crate automation_devices;
 
-fn main() -> std::io::Result<()> {
+fn write_definitions(filename: &str, definitions: &str) -> std::io::Result<()> {
-    tracing_subscriber::fmt::init();
-
     let definitions_directory =
         std::path::Path::new(std::env!("CARGO_MANIFEST_DIR")).join("definitions");
     fs::create_dir_all(&definitions_directory)?;
 
+    let mut file = File::create(definitions_directory.join(filename))?;
+
+    file.write_all(b"-- DO NOT MODIFY, FILE IS AUTOMATICALLY GENERATED\n")?;
+    file.write_all(definitions.as_bytes())?;
+
+    // Make sure we have a trailing new line
+    if !definitions.ends_with("\n") {
+        file.write_all(b"\n")?;
+    }
+
+    Ok(())
+}
+
+fn main() -> std::io::Result<()> {
+    tracing_subscriber::fmt::init();
+
     for module in inventory::iter::<Module> {
         if let Some(definitions) = module.definitions() {
             info!(name = module.get_name(), "Generating definitions");
 
             let filename = format!("{}.lua", module.get_name());
-            let mut file = File::create(definitions_directory.join(filename))?;
+            write_definitions(&filename, &definitions)?;
-
-            file.write_all(b"-- DO NOT MODIFY, FILE IS AUTOMATICALLY GENERATED\n")?;
-            file.write_all(definitions.as_bytes())?;
-            file.write_all(b"\n")?;
         } else {
             warn!(name = module.get_name(), "No definitions");
         }