Add shell completion generation

crates/geth/tests/bootstrap.rs

@@ -160,6 +160,36 @@ fn guide_command_explains_overlay_boundaries() {
     assert!(stdout.contains("all overlay packets must be carried over Iroh"));
 }
 
+#[test]
+fn completions_are_generated_without_daemon() {
+    let home = tempfile::tempdir().expect("tempdir");
+    let output = run_geth(home.path(), &["completions", "bash"]);
+    assert!(
+        output.status.success(),
+        "stderr: {}",
+        String::from_utf8_lossy(&output.stderr)
+    );
+    let stdout = String::from_utf8_lossy(&output.stdout);
+    assert!(stdout.contains("_geth"));
+    assert!(stdout.contains("overlay"));
+    assert!(stdout.contains("completions"));
+}
+
+#[test]
+fn guide_command_explains_completion_installation() {
+    let home = tempfile::tempdir().expect("tempdir");
+    let output = run_geth(home.path(), &["guide", "completions"]);
+    assert!(
+        output.status.success(),
+        "stderr: {}",
+        String::from_utf8_lossy(&output.stderr)
+    );
+    let stdout = String::from_utf8_lossy(&output.stdout);
+    assert!(stdout.contains("geth completions bash"));
+    assert!(stdout.contains("PowerShell"));
+    assert!(stdout.contains("fish"));
+}
+
 #[test]
 fn owner_init_requires_admin_key_and_signing_key() {
     let home = tempfile::tempdir().expect("tempdir");