From 4567565168cae1946b8a9397d31e525802793763 Mon Sep 17 00:00:00 2001
From: kamack38 <64226248+kamack38@users.noreply.github.com>
Date: Thu, 8 Feb 2024 18:51:11 +0100
Subject: [PATCH] =?UTF-8?q?feat(cli):=20=F0=9F=8E=B8=20Add=20command=20com?=
 =?UTF-8?q?pletion=20via=20clap=5Fcompletion?=
MIME-Version: 1.0
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- Add init command
---
 Cargo.lock | 10 ++++++++++
 Cargo.toml |  1 +
 src/cli.rs | 22 ++++++++++++++++++----
 3 files changed, 29 insertions(+), 4 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 17b7cac..7463e92 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -72,6 +72,15 @@ dependencies = [
  "strsim",
 ]
 
+[[package]]
+name = "clap_complete"
+version = "4.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "299353be8209bd133b049bf1c63582d184a8b39fd9c04f15fe65f50f88bdfe6c"
+dependencies = [
+ "clap",
+]
+
 [[package]]
 name = "clap_derive"
 version = "4.4.7"
@@ -125,6 +134,7 @@ name = "ram-machine"
 version = "1.1.0"
 dependencies = [
  "clap",
+ "clap_complete",
  "thiserror",
 ]
 
diff --git a/Cargo.toml b/Cargo.toml
index 5549ddd..c76aa2b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -20,4 +20,5 @@ path = "src/main.rs"
 
 [dependencies]
 clap = { version = "4.4.18", features = ["derive"] }
+clap_complete = "4.5.0"
 thiserror = "1.0.52"
diff --git a/src/cli.rs b/src/cli.rs
index 1bf4049..f10d309 100644
--- a/src/cli.rs
+++ b/src/cli.rs
@@ -11,17 +11,18 @@ use ram_machine::{
     parser::ParserError,
 };
 
-use clap::{Parser as ClapParser, Subcommand};
+use clap::{Command, CommandFactory, Parser as ClapParser, Subcommand, ValueHint};
+use clap_complete::{generate, Generator, Shell};
 
 #[derive(ClapParser, Debug)]
-#[command(author, version, about, long_about = None)]
+#[command(name = "ram", author, version, about, long_about = None)]
 struct Cli {
     /// Specifies the path to the input file from which data will be read (input passed from the command line takes precedence)
-    #[arg(short, long, value_name = "FILE")]
+    #[arg(short, long, value_name = "FILE", value_hint = ValueHint::FilePath)]
     input_file: Option<PathBuf>,
 
     /// Specifies the path to the output file where the results will be written
-    #[arg(short, long, value_name = "FILE")]
+    #[arg(short, long, value_name = "FILE", value_hint = ValueHint::FilePath)]
     output_file: Option<PathBuf>,
 
     /// Don't pass code output to STDOUT
@@ -39,6 +40,9 @@ pub enum Commands {
 
     /// Validates ram code syntax of a given file
     Check { file: PathBuf },
+
+    /// Generate a shell completion file
+    Init { shell: Shell },
     // Repl,
     // Debug,
 }
@@ -67,8 +71,13 @@ pub enum RuntimeError {
     CheckFileError(ParserErrorChain),
 }
 
+fn print_completions<G: Generator>(gen: G, cmd: &mut Command) {
+    generate(gen, cmd, cmd.get_name().to_string(), &mut io::stdout());
+}
+
 pub fn app() -> Result<(), RuntimeError> {
     let cli = Cli::parse();
+
     match cli.command {
         Commands::Run { file, input } => {
             let mut input = input;
@@ -132,6 +141,11 @@ pub fn app() -> Result<(), RuntimeError> {
                 return Err(RuntimeError::CheckFileError(errors));
             }
         }
+        Commands::Init { shell } => {
+            let mut cmd = Cli::command();
+            eprintln!("Generating completion file for {shell:?}...");
+            print_completions(shell, &mut cmd)
+        }
     };
     Ok(())
 }