feat: add command line parsing to rad-ci, with --dry-run option

Signed-off-by: Lars Wirzenius <liw@liw.fi>

Cargo.lock

@@ -384,9 +384,9 @@ dependencies = [
 
 [[package]]
 name = "clap"
-version = "4.5.21"
+version = "4.5.23"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fb3b4b9e5a7c7514dfa52869339ee98b3156b0bfb4e8a77c4ff4babb64b1604f"
+checksum = "3135e7ec2ef7b10c6ed8950f0f792ed96ee093fa088608f1c76e569722700c84"
 dependencies = [
  "clap_builder",
  "clap_derive",
@@ -394,9 +394,9 @@ dependencies = [
 
 [[package]]
 name = "clap_builder"
-version = "4.5.21"
+version = "4.5.23"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b17a95aa67cc7b5ebd32aa5370189aa0d79069ef1c64ce893bd30fb24bff20ec"
+checksum = "30582fc632330df2bd26877bde0c1f4470d57c582bbc070376afcd04d8cb4838"
 dependencies = [
  "anstream",
  "anstyle",
@@ -419,9 +419,9 @@ dependencies = [
 
 [[package]]
 name = "clap_lex"
-version = "0.7.3"
+version = "0.7.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "afb84c814227b90d6895e01398aee0d8033c00e7466aca416fb6a8e0eb19d8a7"
+checksum = "f46ad14479a25103f283c0f10005961cf086d8dc42205bb44c46ac563475dca6"
 
 [[package]]
 name = "colorchoice"
@@ -1971,6 +1971,7 @@ dependencies = [
 name = "radicle-native-ci"
 version = "0.5.0"
 dependencies = [
+ "clap",
  "html-page",
  "radicle",
  "radicle-ci-broker",

Cargo.toml

@@ -12,6 +12,7 @@ repository = "https://app.radicle.xyz/nodes/radicle.liw.fi/rad:z3qg5TKmN83afz2fj
 categories = ["development-tools::build-utils"]
 
 [dependencies]
+clap = { version = "4.5.23", features = ["derive"] }
 html-page = "0.4.0"
 radicle = "0.13.0"
 radicle-ci-broker = "0.8.0"

src/bin/rad-ci.rs

@@ -3,6 +3,7 @@ use std::{
     process::{exit, Command},
 };
 
+use clap::Parser;
 use radicle_native_ci::{run::RUNSPEC_PATH, runspec::RunSpec};
 
 // Exit codes for the program.
@@ -34,8 +35,29 @@ fn main() {
 }
 
 fn fallible_main() -> Result<bool, Box<dyn std::error::Error>> {
+    let args = Args::parse();
     let runspec = RunSpec::from_file(Path::new(RUNSPEC_PATH))?;
     let shell = format!("set -xeuo pipefail\n{}", runspec.shell);
+    if args.dry_run {
+        print!("{shell}");
+        Ok(true)
+    } else {
         let exit = Command::new("bash").args(["-c", &shell]).spawn()?.wait()?;
         Ok(exit.success())
     }
+}
+
+/// Run the commands the Radicle native CI adapter would run for this
+/// repository.
+///
+/// The shell commands are specified in the .radicle/native.yaml file,
+/// in the shell field. They are run directly on the host, using the
+/// Bash shell, without any isolation.
+#[derive(Debug, Parser)]
+#[clap(version)]
+struct Args {
+    /// Don't actually run anything, merely output what would be given
+    /// to Bash to run.
+    #[clap(long, alias = "no-act")]
+    dry_run: bool,
+}