add main error types

crates/main/main.rs

@@ -19,7 +19,6 @@ use std::process::{ExitCode, Termination};
 
 use anyhow::{Context, Result};
 
-use pacdef_core as core;
 use pacdef_core::{get_args, get_config_path, get_group_dir, Config, Group, Pacdef};
 
 fn main() -> ExitCode {
@@ -32,9 +31,7 @@ fn handle_final_result(result: Result<()>) -> ExitCode {
     match result {
         Ok(_) => ExitCode::SUCCESS,
         Err(ref e) => {
-            let msg = e.root_cause().to_string();
-
-            if msg == core::NO_PACKAGES_FOUND {
+            if e.root_cause().to_string() == pacdef_core::Error::NoPackagesFound.to_string() {
                 ExitCode::FAILURE
             } else {
                 result.report()

crates/pacdef_core/src/errors.rs

@@ -0,0 +1,19 @@
+use std::fmt::Display;
+
+/// Error types for pacdef.
+#[derive(Debug)]
+#[non_exhaustive]
+pub enum Error {
+    /// Package search yields no results.
+    NoPackagesFound,
+}
+
+impl Display for Error {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            Self::NoPackagesFound => f.write_str("no packages matching query"),
+        }
+    }
+}
+
+impl std::error::Error for Error {}

crates/pacdef_core/src/lib.rs

@@ -28,6 +28,7 @@ mod cmd;
 mod config;
 mod core;
 mod env;
+mod errors;
 mod grouping;
 mod path;
 mod review;
@@ -37,9 +38,9 @@ mod ui;
 pub use crate::args::get as get_args;
 pub use crate::config::Config;
 pub use crate::core::Pacdef;
+pub use crate::errors::Error;
 pub use crate::grouping::Group;
 pub(crate) use crate::grouping::Package;
 pub use crate::path::{get_config_path, get_group_dir};
-pub use crate::search::NO_PACKAGES_FOUND;
 
 extern crate pacdef_macros;

crates/pacdef_core/src/search.rs

@@ -8,9 +8,6 @@ use regex::Regex;
 
 use crate::grouping::{Group, Package, Section};
 
-/// Error message provided when a package search yields no results.
-pub const NO_PACKAGES_FOUND: &str = "no packages matching query";
-
 pub fn search_packages(args: &ArgMatches, groups: &HashSet<Group>) -> Result<()> {
     let search_string = args
         .get_one::<String>("string")
@@ -31,7 +28,7 @@ pub fn search_packages(args: &ArgMatches, groups: &HashSet<Group>) -> Result<()>
     }
 
     if vec.is_empty() {
-        bail!(NO_PACKAGES_FOUND)
+        bail!(crate::errors::Error::NoPackagesFound);
     }
 
     print_triples(vec);