docs: add docstrings to two methods

crates/pacdef_core/src/backend/todo_per_backend.rs

@@ -6,6 +6,11 @@ use anyhow::{bail, ensure, Context, Result};
 use super::Backend;
 use crate::Package;
 
+/// A vector of tuples containing a `dyn Backend` and a vector of unmanaged packages
+/// for that backend.
+///
+/// This struct is used to store a list of unmanaged packages or missing packages
+/// for all backends.
 #[derive(Debug)]
 pub struct ToDoPerBackend(Vec<(Box<dyn Backend>, Vec<Package>)>);
 

crates/pacdef_core/src/core.rs

@@ -178,6 +178,13 @@ impl Pacdef {
             .context("printing things to do")
     }
 
+    /// Get a list of unmanaged packages per backend.
+    ///
+    /// This method loops through all enabled `Backend`s whose binary is in `PATH`.
+    ///
+    /// # Errors
+    ///
+    /// This function will propagate errors.
     fn get_unmanaged_packages(&mut self) -> Result<ToDoPerBackend> {
         let mut result = ToDoPerBackend::new();