Add ability to generate shell completions

src/app.rs

@@ -4,6 +4,7 @@ use std::{
     process::Command,
 };
 
+use clap::CommandFactory;
 use colored::Colorize;
 use glob::glob;
 
@@ -41,6 +42,28 @@ enum Subcommand {
     },
     /// Clean all in progress files
     Clean,
+    /// Utility functions
+    Utils {
+        #[clap(subcommand)]
+        command: UtilSubcommand,
+    },
+}
+
+#[derive(clap::Subcommand)]
+enum UtilSubcommand {
+    /// Generate shell completions
+    Completions {
+        /// The shell to generate completions for
+        shell: ShellCompletions,
+    },
+}
+
+#[derive(Clone, clap::ValueEnum)]
+enum ShellCompletions {
+    Bash,
+    Fish,
+    PowerShell,
+    Zsh,
 }
 
 impl App {
@@ -87,6 +110,38 @@ impl App {
                 }
                 _ => {}
             },
+            Subcommand::Utils { command } => match command {
+                UtilSubcommand::Completions { shell } => {
+                    let name = env!("CARGO_PKG_NAME");
+                    let mut command = App::command();
+                    match shell {
+                        ShellCompletions::Bash => clap_complete::generate(
+                            clap_complete::shells::Bash,
+                            &mut command,
+                            name,
+                            &mut std::io::stdout(),
+                        ),
+                        ShellCompletions::Fish => clap_complete::generate(
+                            clap_complete::shells::Fish,
+                            &mut command,
+                            name,
+                            &mut std::io::stdout(),
+                        ),
+                        ShellCompletions::PowerShell => clap_complete::generate(
+                            clap_complete::shells::PowerShell,
+                            &mut command,
+                            name,
+                            &mut std::io::stdout(),
+                        ),
+                        ShellCompletions::Zsh => clap_complete::generate(
+                            clap_complete::shells::Zsh,
+                            &mut command,
+                            name,
+                            &mut std::io::stdout(),
+                        ),
+                    }
+                }
+            },
         }
     }
 }