Complete the end-to-end CLI parity audit

crates/storage/src/command.rs

@@ -3,12 +3,13 @@
 use std::{error::Error, ffi::OsString, fmt, num::NonZeroUsize, path::PathBuf};
 
 use clap::{Args, CommandFactory, Parser, Subcommand, error::ErrorKind};
+use clap_complete::{Shell, generate};
 
 use crate::PRODUCT_NAME;
 
 pub const EXIT_SUCCESS: u8 = 0;
 pub const EXIT_FAILURE: u8 = 1;
-pub const EXIT_USAGE: u8 = 2;
+pub const EXIT_USAGE: u8 = EXIT_FAILURE;
 pub const EXIT_UNAVAILABLE: u8 = 69;
 pub const EXIT_CONFIG: u8 = 78;
 
@@ -53,10 +54,32 @@ pub enum CommandRequest {
     Copy(CopyRequest),
     Git(GitRequest),
     Otp(OtpRequest),
+    Completion { shell: CompletionShell },
     Help { topic: Option<HelpTopic> },
     Version,
 }
 
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub enum CompletionShell {
+    Bash,
+    Elvish,
+    Fish,
+    PowerShell,
+    Zsh,
+}
+
+impl CompletionShell {
+    fn generator(self) -> Shell {
+        match self {
+            Self::Bash => Shell::Bash,
+            Self::Elvish => Shell::Elvish,
+            Self::Fish => Shell::Fish,
+            Self::PowerShell => Shell::PowerShell,
+            Self::Zsh => Shell::Zsh,
+        }
+    }
+}
+
 #[derive(Clone, Debug, Eq, PartialEq)]
 pub struct InitRequest {
     pub path: Option<String>,
@@ -417,6 +440,13 @@ pub fn otp_version_text() -> &'static str {
     "1.1.1\n"
 }
 
+pub fn completion_script(shell: CompletionShell) -> Vec<u8> {
+    let mut command = CliArguments::command();
+    let mut output = Vec::new();
+    generate(shell.generator(), &mut command, "ironstorage", &mut output);
+    output
+}
+
 #[derive(Parser)]
 #[command(
     name = "ironstorage",
@@ -452,10 +482,26 @@ enum CommandArguments {
     Copy(CopyArguments),
     Git(GitArguments),
     Otp(OtpArguments),
+    Completion(CompletionArguments),
     Help(HelpArguments),
     Version,
 }
 
+#[derive(Args)]
+struct CompletionArguments {
+    #[arg(value_enum)]
+    shell: CompletionShellArgument,
+}
+
+#[derive(Clone, Copy, clap::ValueEnum)]
+enum CompletionShellArgument {
+    Bash,
+    Elvish,
+    Fish,
+    Powershell,
+    Zsh,
+}
+
 #[derive(Args)]
 struct InitArguments {
     #[arg(short = 'p', long = "path")]
@@ -784,6 +830,15 @@ fn convert_arguments(arguments: CliArguments) -> Result<CliInvocation, CliParseE
         Some(CommandArguments::Otp(arguments)) => {
             CommandRequest::Otp(convert_otp(arguments.command)?)
         }
+        Some(CommandArguments::Completion(arguments)) => CommandRequest::Completion {
+            shell: match arguments.shell {
+                CompletionShellArgument::Bash => CompletionShell::Bash,
+                CompletionShellArgument::Elvish => CompletionShell::Elvish,
+                CompletionShellArgument::Fish => CompletionShell::Fish,
+                CompletionShellArgument::Powershell => CompletionShell::PowerShell,
+                CompletionShellArgument::Zsh => CompletionShell::Zsh,
+            },
+        },
         Some(CommandArguments::Help(arguments)) => {
             let topic = arguments
                 .topic
@@ -914,9 +969,29 @@ fn normalize_dispatch(mut arguments: Vec<OsString>) -> Vec<OsString> {
     };
     let command = arguments[command_index].to_string_lossy();
     const ROOT_COMMANDS: &[&str] = &[
-        "init", "ls", "list", "show", "find", "search", "grep", "insert", "add", "edit",
-        "generate", "rm", "remove", "delete", "mv", "rename", "cp", "copy", "git", "otp", "help",
+        "init",
+        "ls",
+        "list",
+        "show",
+        "find",
+        "search",
+        "grep",
+        "insert",
+        "add",
+        "edit",
+        "generate",
+        "rm",
+        "remove",
+        "delete",
+        "mv",
+        "rename",
+        "cp",
+        "copy",
+        "git",
+        "otp",
+        "help",
         "version",
+        "completion",
     ];
     if !ROOT_COMMANDS.contains(&command.as_ref()) && !command.starts_with('-') {
         arguments.insert(command_index, OsString::from("show"));
@@ -998,7 +1073,9 @@ fn normalize_otp_dispatch(arguments: &mut Vec<OsString>, mut index: usize) {
     const OTP_COMMANDS: &[&str] = &[
         "code", "show", "insert", "add", "append", "uri", "validate", "help", "version",
     ];
-    if argument == "--version" {
+    if argument == "help" {
+        arguments[index] = OsString::from("--help");
+    } else if argument == "--version" {
         arguments[index] = OsString::from("version");
     } else if !OTP_COMMANDS.contains(&argument.as_ref()) && argument != "--help" && argument != "-h"
     {