doc: Add note to to-do: must clean up the syntax of the error handling in setup().

TODO.md

@@ -1,2 +1,4 @@
 # To-do
 - Report that "ReadableConfig" error, which was super unhelpful and very annoying when you don't know why it's bugging.
+- Find a better notation for the error-handling in setup() – although the custom error message is desirable, it's very bad
+to have to implement it using such a ridiculously long line...

src/main.rs

@@ -42,7 +42,7 @@ enum Action {
 }
 
 fn setup(args: SetupArgs) -> Result<(), std::io::Error> {
-    if let Ok(config_template) = std::fs::read_to_string(CONFIG_TEMPLATE_PATH) {
+    let config_template = std::fs::read_to_string(CONFIG_TEMPLATE_PATH).or(Err(std::io::Error::new(std::io::ErrorKind::NotFound, format!("Unable to find {}; did you execute the script from the same directory?", CONFIG_TEMPLATE_PATH))))?;
     let filled_in_config = formatx!(config_template, args.api_url, args.rest_url, args.username, args.botpassword, args.oauth2_token).unwrap();
     let path = shellexpand::tilde(BOT_CONFIG_PATH).into_owned();
     std::fs::write(&path, filled_in_config).unwrap();
@@ -51,9 +51,6 @@ fn setup(args: SetupArgs) -> Result<(), std::io::Error> {
         std::fs::set_permissions(path, std::fs::Permissions::from_mode(0o600))?;
     }
     Ok(())
-    } else {
-        Err(std::io::Error::new(std::io::ErrorKind::NotFound, format!("Unable to find {}; did you execute the script from the same directory?", CONFIG_TEMPLATE_PATH)))
-    }
 }
 
 #[tokio::main]