fix: correct output of shell completions

src/completions.rs

@@ -1,23 +1,27 @@
 use clap::CommandFactory;
 use clap_complete::{generate, Shell};
 use clap_complete_nushell::Nushell;
-use std::io::{self, Write};
+use std::io::{Error, ErrorKind, Result, Write};
 use std::str::FromStr;
 
 use crate::args;
 
-pub fn generate_shell_completions(shell_s: &str, buf: &mut dyn Write) {
+pub fn generate_shell_completions(shell_s: &str, buf: &mut dyn Write) -> Result<()> {
     if "nu" == shell_s || "nushell" == shell_s {
         let shell = Nushell;
         generate(shell, &mut args::Args::command(), "rip", buf);
     } else {
-        let shell = Shell::from_str(shell_s).unwrap_or_else(|_| {
-            eprintln!(
-                "Invalid shell specification: {}. Available shells: bash, elvish, fish, powershell, zsh, nushell",
-                shell_s
-            );
-            std::process::exit(1);
-        });
-        generate(shell, &mut args::Args::command(), "rip", buf);
+        let tryshell = Shell::from_str(shell_s);
+        if tryshell.is_err() {
+            return Err(Error::new(
+                ErrorKind::InvalidInput,
+                format!(
+                    "Invalid shell specification: {}. Available shells: bash, elvish, fish, powershell, zsh, nushell",
+                    shell_s
+                )
+            ));
+        }
+        generate(tryshell.unwrap(), &mut args::Args::command(), "rip", buf);
     }
+    Ok(())
 }

src/lib.rs

@@ -7,9 +7,9 @@ use std::{env, fs};
 use walkdir::WalkDir;
 
 pub mod args;
+pub mod completions;
 pub mod record;
 pub mod util;
-pub mod completions;
 
 use args::Args;
 use record::{Record, RecordItem};

src/main.rs

@@ -2,22 +2,25 @@ use clap::Parser;
 use std::io;
 use std::process::ExitCode;
 
-use rip2::{args, util, completions};
+use rip2::{args, completions, util};
 
 fn main() -> ExitCode {
     let cli = args::Args::parse();
+    let mut stream = io::stdout();
+    let mode = util::ProductionMode;
 
     match &cli.command {
         Some(args::Commands::Completions { shell }) => {
-            completions::generate_shell_completions(shell);
+            let result = completions::generate_shell_completions(shell, &mut io::stdout());
+            if result.is_err() {
+                eprintln!("{}", result.unwrap_err());
+                return ExitCode::FAILURE;
+            }
             return ExitCode::SUCCESS;
         }
         None => {}
     }
 
-    let mode = util::ProductionMode;
-    let mut stream = io::stdout();
-
     if let Err(ref e) = rip2::run(cli, mode, &mut stream) {
         println!("Exception: {}", e);
         return ExitCode::FAILURE;