major overhaul of Backend from dynamic to static dispatch using an big enum

crates/pacdef/src/backend/mod.rs

@@ -1,26 +1,52 @@
-mod actual;
-mod backend_trait;
-mod iter;
-mod macros;
+pub mod actual;
+pub mod backend_trait;
+pub mod macros;
 mod root;
-mod todo_per_backend;
+pub mod todo_per_backend;
 
-pub use backend_trait::Backend;
-pub use iter::BackendIter;
-pub use todo_per_backend::ToDoPerBackend;
+use crate::backend::backend_trait::Switches;
+use crate::backend::backend_trait::Text;
+use crate::Group;
+use crate::Package;
+use anyhow::Result;
+use backend_trait::Backend;
+use std::collections::HashSet;
+use std::rc::Rc;
 
-use pacdef_macros::Register;
+use self::actual::{
+    fedora::Fedora, flatpak::Flatpak, python::Python, rust::Rust, rustup::Rustup, void::Void,
+};
 
-#[derive(Debug, Register)]
-pub enum Backends {
+#[derive(Debug)]
+#[enum_dispatch::enum_dispatch(Backend)]
+pub enum AnyBackend {
     #[cfg(feature = "arch")]
-    Arch,
+    Arch(actual::arch::Arch),
     #[cfg(feature = "debian")]
-    Debian,
-    Flatpak,
-    Fedora,
-    Python,
-    Rust,
-    Rustup,
-    Void,
+    Debian(actual::debian::Debian),
+    Flatpak(Flatpak),
+    Fedora(Fedora),
+    Python(Python),
+    Rust(Rust),
+    Rustup(Rustup),
+    Void(Void),
+}
+
+impl AnyBackend {
+    /// Returns an iterator of every variant of backend.
+    pub fn iter() -> impl Iterator<Item = Self> {
+        vec![
+            #[cfg(feature = "arch")]
+            Self::Arch(actual::arch::Arch::new()),
+            #[cfg(feature = "debian")]
+            Self::Debian(actual::debian::Debian::new()),
+            Self::Flatpak(Flatpak::new()),
+            Self::Fedora(Fedora::new()),
+            Self::Python(Python::new()),
+            Self::Rust(Rust::new()),
+            Self::Rustup(Rustup::new()),
+            Self::Void(Void::new()),
+        ]
+        .into_iter()
+    }
 }