Add rpm-ostree experimental

ci/test-container.sh

@@ -50,6 +50,10 @@ if ! grep -qe "error.*This system was not booted via libostree" err.txt; then
     fatal "did not find expected error"
 fi
 
+# This does nothing, just verifies the experimental CLI works.
+rpm-ostree experimental stub >out.txt
+grep 'Did nothing successfully' out.txt && rm out.txt
+
 rpm-ostree install testdaemon
 grep -qF 'u testdaemon-user' /usr/lib/sysusers.d/35-rpmostree-pkg-user-testdaemon-user.conf
 grep -qF 'g testdaemon-group' /usr/lib/sysusers.d/30-rpmostree-pkg-group-testdaemon-group.conf

rust/src/cli_experimental.rs

@@ -0,0 +1,51 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
+use anyhow::Result;
+use clap::Parser;
+
+#[derive(Debug, Parser)]
+#[clap(rename_all = "kebab-case")]
+/// Main options struct
+struct Experimental {
+    #[clap(subcommand)]
+    cmd: Cmd,
+}
+
+#[derive(Debug, clap::Subcommand)]
+#[clap(rename_all = "kebab-case")]
+/// Subcommands
+enum Cmd {
+    /// This command does nothing, it's a placeholder for future expansion.
+    #[clap(hide = true)]
+    Stub,
+}
+
+impl Cmd {
+    fn run(self) -> Result<()> {
+        match self {
+            Cmd::Stub => println!("Did nothing successfully."),
+        }
+        Ok(())
+    }
+}
+
+/// Primary entrypoint to running our wrapped `yum`/`dnf` handling.
+pub fn main(argv: &[&str]) -> Result<i32> {
+    let opt = Experimental::parse_from(argv.into_iter().skip(1));
+    opt.cmd.run()?;
+    Ok(0)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_parse() -> Result<()> {
+        let opt = Experimental::try_parse_from(["experimental", "stub"]).unwrap();
+        match opt.cmd {
+            Cmd::Stub => {}
+        }
+        Ok(())
+    }
+}

rust/src/lib.rs

@@ -971,6 +971,7 @@ pub(crate) use composepost::*;
 mod core;
 use crate::core::*;
 mod capstdext;
+pub mod cli_experimental;
 mod daemon;
 pub(crate) use daemon::*;
 mod deployment_utils;

rust/src/main.rs

@@ -41,6 +41,9 @@ async fn inner_async_main(args: Vec<String>) -> Result<i32> {
                     rpmostree_rust::container::container_encapsulate(args_orig).map(|_| 0)
                     .map_err(anyhow::Error::msg)
                 },
+                "experimental" => {
+                    rpmostree_rust::cli_experimental::main(args)
+                }
                 // C++ main
                 _ => Ok(rpmostree_rust::ffi::rpmostree_main(args)?),
             }