add Debug supertrait for Backend

src/backend/actual/pacman.rs

@@ -8,6 +8,7 @@ use anyhow::{Context, Result};
 use crate::backend::backend_trait::*;
 use crate::{impl_backend_constants, Group, Package};
 
+#[derive(Debug)]
 pub(crate) struct Pacman {
     pub(crate) binary: String,
     pub(crate) aur_rm_args: Option<Vec<String>>,

src/backend/actual/rust.rs

@@ -8,6 +8,7 @@ use serde_json::Value;
 use crate::backend::backend_trait::*;
 use crate::{impl_backend_constants, Group, Package};
 
+#[derive(Debug)]
 pub(crate) struct Rust {
     pub(crate) packages: HashSet<Package>,
 }

src/backend/backend_trait.rs

@@ -1,3 +1,4 @@
+use std::fmt::Debug;
 use std::process::Command;
 use std::{collections::HashSet, process::ExitStatus};
 
@@ -8,7 +9,7 @@ use crate::{Group, Package};
 pub(in crate::backend) type Switches = &'static [&'static str];
 pub(in crate::backend) type Text = &'static str;
 
-pub(crate) trait Backend {
+pub(crate) trait Backend: Debug {
     fn get_binary(&self) -> Text;
     fn get_section(&self) -> Text;
     fn get_switches_install(&self) -> Switches;

src/backend/todo_per_backend.rs

@@ -5,6 +5,7 @@ use anyhow::{bail, ensure, Context, Result};
 use super::Backend;
 use crate::Package;
 
+#[derive(Debug)]
 pub(crate) struct ToDoPerBackend(Vec<(Box<dyn Backend>, Vec<Package>)>);
 
 impl ToDoPerBackend {