From f291e03fd7d94fae02ba5bfd9f1845f5b635ebc5 Mon Sep 17 00:00:00 2001
From: Finley Thomalla <finley@thomalla.ch>
Date: Wed, 13 Nov 2024 15:58:51 +0100
Subject: [PATCH] feat: add shell completions subcommand (#106)

Adds a subcommand "completions" which can generate shell completions for
a few supported shells, namely bash, zsh and Nushell.
You can use it like this: `koji completions <SHELL> >
<CUSTOM_COMPLETIONS_DIR>/_koji`.
I consider this feature necessary for eventually publishing koji to
other package registries, such as the AUR.
---
 Cargo.lock      | 31 +++++++++++++++++++++++++++++++
 Cargo.toml      |  1 +
 README.md       |  2 ++
 src/bin/main.rs | 21 ++++++++++++++++++++-
 4 files changed, 54 insertions(+), 1 deletion(-)

diff --git a/Cargo.lock b/Cargo.lock
index fac1e66..b662932 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -215,6 +215,36 @@ dependencies = [
  "strsim",
 ]
 
+[[package]]
+name = "clap_complete"
+version = "4.5.37"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "11611dca53440593f38e6b25ec629de50b14cdfa63adc0fb856115a2c6d97595"
+dependencies = [
+ "clap",
+]
+
+[[package]]
+name = "clap_complete_command"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "da8e198c052315686d36371e8a3c5778b7852fc75cc313e4e11eeb7a644a1b62"
+dependencies = [
+ "clap",
+ "clap_complete",
+ "clap_complete_nushell",
+]
+
+[[package]]
+name = "clap_complete_nushell"
+version = "4.5.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "315902e790cc6e5ddd20cbd313c1d0d49db77f191e149f96397230fb82a17677"
+dependencies = [
+ "clap",
+ "clap_complete",
+]
+
 [[package]]
 name = "clap_derive"
 version = "4.5.18"
@@ -901,6 +931,7 @@ version = "2.2.0"
 dependencies = [
  "anyhow",
  "clap",
+ "clap_complete_command",
  "cocogitto",
  "conventional_commit_parser",
  "dirs",
diff --git a/Cargo.toml b/Cargo.toml
index 9ffba59..7d2d29b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -31,6 +31,7 @@ indexmap = "2.1"
 serde = { version = "1.0", features = ["derive"] }
 toml = "0.8"
 inquire = "0.7.5"
+clap_complete_command = { version = "0.6.1", features = ["nushell"]}
 
 [features]
 vendored-openssl = ["git2/vendored-openssl"]
diff --git a/README.md b/README.md
index 8a17e31..d2ddda9 100644
--- a/README.md
+++ b/README.md
@@ -58,6 +58,8 @@ koji
 
 See `koji --help` for more options.
 
+Use `koji completions <SHELL>` to generate completion scripts for your shell.
+
 ## Using as a git hook
 
 An alternative way to use koji is as a [git hook](https://git-scm.com/book/en/v2/Customizing-Git-Git-Hooks),
diff --git a/src/bin/main.rs b/src/bin/main.rs
index f620ffa..42fd5a7 100644
--- a/src/bin/main.rs
+++ b/src/bin/main.rs
@@ -1,7 +1,7 @@
 use std::fs::read_to_string;
 
 use anyhow::{Context, Result};
-use clap::Parser;
+use clap::{CommandFactory, Parser, Subcommand};
 use cocogitto::command::commit::CommitOptions;
 use conventional_commit_parser::parse;
 use git2::Repository;
@@ -16,6 +16,9 @@ use koji::questions::create_prompt;
     version
 )]
 struct Args {
+    #[command(subcommand)]
+    command: Option<SubCmds>,
+
     #[arg(
         long,
         default_missing_value = "true",
@@ -86,10 +89,17 @@ struct Args {
     all: bool,
 }
 
+#[derive(Debug, Subcommand)]
+enum SubCmds {
+    #[command(about = "Generate shell completions")]
+    Completions { shell: clap_complete_command::Shell },
+}
+
 #[cfg(not(tarpaulin_include))]
 fn main() -> Result<()> {
     // Get CLI args
     let Args {
+        command,
         autocomplete,
         breaking_changes,
         config,
@@ -100,6 +110,15 @@ fn main() -> Result<()> {
         all,
     } = Args::parse();
 
+    if command.is_some() {
+        match command.unwrap() {
+            SubCmds::Completions { shell } => {
+                shell.generate(&mut Args::command(), &mut std::io::stdout());
+            }
+        }
+        return Ok(());
+    }
+
     // Find repo
     let repo =
         Repository::discover(std::env::current_dir()?).context("could not find git repository")?;