implement generic backend methods with a macro

src/backend/macros.rs

@@ -0,0 +1,20 @@
+#[macro_export]
+macro_rules! impl_backend_constants {
+    ($name:ident) => {
+        fn get_binary(&self) -> Text {
+            BINARY
+        }
+
+        fn get_section(&self) -> Text {
+            SECTION
+        }
+
+        fn get_switches_install(&self) -> Switches {
+            SWITCHES_INSTALL
+        }
+
+        fn get_switches_remove(&self) -> Switches {
+            SWITCHES_REMOVE
+        }
+    };
+}

src/backend/mod.rs

@@ -1,3 +1,4 @@
+mod macros;
 mod pacman;
 mod rust;
 

src/backend/pacman.rs

@@ -4,7 +4,7 @@ use alpm::Alpm;
 use alpm::PackageReason::Explicit;
 
 use super::{Backend, Switches, Text};
-use crate::Package;
+use crate::{impl_backend_constants, Package};
 
 pub struct Pacman {
     pub packages: HashSet<Package>,
@@ -16,21 +16,7 @@ const SWITCHES_INSTALL: Switches = &["-S"];
 const SWITCHES_REMOVE: Switches = &["-Rsn"];
 
 impl Backend for Pacman {
-    fn get_binary(&self) -> Text {
+    impl_backend_constants!(Pacman);
-        BINARY
-    }
-
-    fn get_section(&self) -> Text {
-        SECTION
-    }
-
-    fn get_switches_install(&self) -> Switches {
-        SWITCHES_INSTALL
-    }
-
-    fn get_switches_remove(&self) -> Switches {
-        SWITCHES_REMOVE
-    }
 
     fn get_all_installed_packages(&self) -> HashSet<Package> {
         convert_to_pacdef_packages(get_all_installed_packages_from_alpm())

src/backend/rust.rs

@@ -1,7 +1,7 @@
 use std::{collections::HashSet, process::Command};
 
 use super::{Backend, Switches, Text};
-use crate::Package;
+use crate::{impl_backend_constants, Package};
 
 pub struct Rust {
     pub packages: HashSet<Package>,
@@ -13,21 +13,7 @@ const SWITCHES_INSTALL: Switches = &["install"];
 const SWITCHES_REMOVE: Switches = &["uninstall"];
 
 impl Backend for Rust {
-    fn get_binary(&self) -> Text {
+    impl_backend_constants!(Rust);
-        BINARY
-    }
-
-    fn get_section(&self) -> Text {
-        SECTION
-    }
-
-    fn get_switches_install(&self) -> Switches {
-        SWITCHES_INSTALL
-    }
-
-    fn get_switches_remove(&self) -> Switches {
-        SWITCHES_REMOVE
-    }
 
     fn get_all_installed_packages(&self) -> HashSet<Package> {
         extract_packages_names(&run_cargo_install_list())