Add more clap tests.

Bug: 260823636
Test: atest compos_verify.test fd_server.test initrd_bootconfig.test composd_cmd.test
Change-Id: I7fe3fbf5b8c349618ccdef2f096b77737eabed42
diff --git a/microdroid/initrd/Android.bp b/microdroid/initrd/Android.bp
index 4531583..7a95ce6 100644
--- a/microdroid/initrd/Android.bp
+++ b/microdroid/initrd/Android.bp
@@ -12,6 +12,17 @@
     prefer_rlib: true,
 }
 
+rust_test_host {
+    name: "initrd_bootconfig.test",
+    srcs: ["src/main.rs"],
+    rustlibs: [
+        "libanyhow",
+        "libclap",
+    ],
+    prefer_rlib: true,
+    test_suites: ["general-tests"],
+}
+
 python_binary_host {
     name: "gen_vbmeta_bootconfig",
     srcs: ["gen_vbmeta_bootconfig.py"],
diff --git a/microdroid/initrd/src/main.rs b/microdroid/initrd/src/main.rs
index 69c6ae4..0edb650 100644
--- a/microdroid/initrd/src/main.rs
+++ b/microdroid/initrd/src/main.rs
@@ -72,3 +72,15 @@
 fn main() {
     try_main().unwrap()
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use clap::CommandFactory;
+
+    #[test]
+    fn verify_args() {
+        // Check that the command parsing has been configured in a valid way.
+        Args::command().debug_assert();
+    }
+}