From a4c900c9a7c0f17375dd5034734d617fa37cf9bc Mon Sep 17 00:00:00 2001
From: steven-omaha <35634100+steven-omaha@users.noreply.github.com>
Date: Wed, 22 Feb 2023 12:29:02 +0100
Subject: [PATCH] add error NoGroupFilesInArguments

---
 TODO.md                          | 3 ---
 crates/main/main.rs              | 8 +++++++-
 crates/pacdef_core/src/args.rs   | 3 ++-
 crates/pacdef_core/src/core.rs   | 5 +++--
 crates/pacdef_core/src/errors.rs | 3 +++
 5 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/TODO.md b/TODO.md
index f17891c..9aeadfa 100644
--- a/TODO.md
+++ b/TODO.md
@@ -1,9 +1,6 @@
 # To Do
 
 - make transition for existing user easier
-- create an outer error type for main
 - change version names (1.0.0-beta.10)
 - tutorial
 - update completion for new subcommands (WIP)
-- outer error types:
-    - no group files provided (pacdef group new --edit)
diff --git a/crates/main/main.rs b/crates/main/main.rs
index 5b4f357..1afc302 100644
--- a/crates/main/main.rs
+++ b/crates/main/main.rs
@@ -27,11 +27,17 @@ fn main() -> ExitCode {
 
 /// Skip printing the error chain when searching packages yields no results, otherwise report error
 /// chain.
+#[allow(clippy::option_if_let_else)]
 fn handle_final_result(result: Result<()>) -> ExitCode {
     match result {
         Ok(_) => ExitCode::SUCCESS,
         Err(ref e) => {
-            if e.root_cause().to_string() == pacdef_core::Error::NoPackagesFound.to_string() {
+            if let Some(pacdef_err) = e.root_cause().downcast_ref::<pacdef_core::Error>() {
+                match pacdef_err {
+                    pacdef_core::Error::NoPackagesFound => (),
+                    pacdef_core::Error::NoGroupFilesInArguments => eprintln!("{pacdef_err}"),
+                    _ => eprintln!("unexpected error"),
+                };
                 ExitCode::FAILURE
             } else {
                 result.report()
diff --git a/crates/pacdef_core/src/args.rs b/crates/pacdef_core/src/args.rs
index f49059c..3843b1f 100644
--- a/crates/pacdef_core/src/args.rs
+++ b/crates/pacdef_core/src/args.rs
@@ -45,7 +45,8 @@ fn get_group_cmd() -> Command {
                 .short('e')
                 .long("edit")
                 .help("edit the new group files after creation")
-                .action(clap::ArgAction::SetTrue),
+                .action(clap::ArgAction::SetTrue)
+                .num_args(0),
         )
         .arg(Arg::new("groups").num_args(1..))
         .visible_alias("n");
diff --git a/crates/pacdef_core/src/core.rs b/crates/pacdef_core/src/core.rs
index 4562402..f61d341 100644
--- a/crates/pacdef_core/src/core.rs
+++ b/crates/pacdef_core/src/core.rs
@@ -315,8 +315,9 @@ fn get_group_file_paths_matching_args<'a>(
     groups: &'a HashSet<Group>,
 ) -> Result<Vec<&'a Path>> {
     let file_names: Vec<_> = arg_match
-        .get_many::<String>("group")
-        .context("getting groups from args")?
+        .get_many::<String>("groups")
+        .context("getting groups from args")
+        .map_err(|_| crate::errors::Error::NoGroupFilesInArguments)?
         .collect();
 
     let name_group_map: HashMap<&str, &Group> =
diff --git a/crates/pacdef_core/src/errors.rs b/crates/pacdef_core/src/errors.rs
index e597007..0f19be0 100644
--- a/crates/pacdef_core/src/errors.rs
+++ b/crates/pacdef_core/src/errors.rs
@@ -7,12 +7,15 @@ use std::fmt::Display;
 pub enum Error {
     /// Package search yields no results.
     NoPackagesFound,
+    /// No group files were provided as arguments.
+    NoGroupFilesInArguments,
 }
 
 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"),
+            Self::NoGroupFilesInArguments => f.write_str("no group files in arguments"),
         }
     }
 }