improve error handling

src/backend/actual/pacman.rs

@@ -18,10 +18,10 @@ pub(crate) struct Pacman {
 const BINARY: Text = "paru";
 const SECTION: Text = "pacman";
 
-const SWITCHES_INFO: Switches = &["-Qi"];
-const SWITCHES_INSTALL: Switches = &["-S"];
-const SWITCHES_MAKE_DEPENDENCY: Switches = &["-D", "--asdeps"];
-const SWITCHES_REMOVE: Switches = &["-Rsn"];
+const SWITCHES_INFO: Switches = &["--query", "--info"];
+const SWITCHES_INSTALL: Switches = &["--sync"];
+const SWITCHES_MAKE_DEPENDENCY: Switches = &["--database", "--asdeps"];
+const SWITCHES_REMOVE: Switches = &["--remove", "--recursive"];
 
 impl Backend for Pacman {
     impl_backend_constants!();

src/backend/todo_per_backend.rs

@@ -31,10 +31,12 @@ impl ToDoPerBackend {
 
     pub(crate) fn install_missing_packages(&self) -> Result<()> {
         self.handle_backend_command(Backend::install_packages, "install", "installing")
+            .context("installing packages")
     }
 
     pub(crate) fn remove_unmanaged_packages(&self) -> Result<()> {
         self.handle_backend_command(Backend::remove_packages, "remove", "removing")
+            .context("removing packages")
     }
 
     fn handle_backend_command<'a, F>(

src/core.rs

@@ -3,7 +3,7 @@ use std::fs::{remove_file, File};
 use std::os::unix::fs::symlink;
 use std::path::PathBuf;
 
-use anyhow::{ensure, Context, Result};
+use anyhow::{anyhow, ensure, Context, Result};
 use clap::ArgMatches;
 
 use crate::action::*;
@@ -189,7 +189,11 @@ impl Pacdef {
         let mut iter = groups.get_many::<String>("group").unwrap().peekable();
 
         while let Some(arg_group) = iter.next() {
-            let group = self.groups.iter().find(|g| g.name == *arg_group).unwrap();
+            let group = self
+                .groups
+                .iter()
+                .find(|g| g.name == *arg_group)
+                .ok_or_else(|| anyhow!("group {} not found", *arg_group))?;
             println!("{group}");
             if iter.peek().is_some() {
                 println!();