fix(test suite): some tests leak child processes (#6497)

control_plane/src/endpoint.rs

@@ -438,7 +438,7 @@ impl Endpoint {
     }
 
     fn wait_for_compute_ctl_to_exit(&self, send_sigterm: bool) -> Result<()> {
-        // TODO use background_process::stop_process instead
+        // TODO use background_process::stop_process instead: https://github.com/neondatabase/neon/pull/6482
         let pidfile_path = self.endpoint_path().join("compute_ctl.pid");
         let pid: u32 = std::fs::read_to_string(pidfile_path)?.parse()?;
         let pid = nix::unistd::Pid::from_raw(pid as i32);
@@ -583,9 +583,21 @@ impl Endpoint {
         }
 
         let child = cmd.spawn()?;
+        // set up a scopeguard to kill & wait for the child in case we panic or bail below
+        let child = scopeguard::guard(child, |mut child| {
+            println!("SIGKILL & wait the started process");
+            (|| {
+                // TODO: use another signal that can be caught by the child so it can clean up any children it spawned
+                child.kill().context("SIGKILL child")?;
+                child.wait().context("wait() for child process")?;
+                anyhow::Ok(())
+            })()
+            .with_context(|| format!("scopeguard kill&wait child {child:?}"))
+            .unwrap();
+        });
 
         // Write down the pid so we can wait for it when we want to stop
-        // TODO use background_process::start_process instead
+        // TODO use background_process::start_process instead: https://github.com/neondatabase/neon/pull/6482
         let pid = child.id();
         let pidfile_path = self.endpoint_path().join("compute_ctl.pid");
         std::fs::write(pidfile_path, pid.to_string())?;
@@ -634,6 +646,9 @@ impl Endpoint {
             std::thread::sleep(ATTEMPT_INTERVAL);
         }
 
+        // disarm the scopeguard, let the child outlive this function (and neon_local invoction)
+        drop(scopeguard::ScopeGuard::into_inner(child));
+
         Ok(())
     }
 

test_runner/regress/test_import.py

@@ -163,6 +163,8 @@ def test_import_from_vanilla(test_output_dir, pg_bin, vanilla_pg, neon_env_build
     endpoint = env.endpoints.create_start(endpoint_id, tenant_id=tenant)
     assert endpoint.safe_psql("select count(*) from t") == [(300000,)]
 
+    vanilla_pg.stop()
+
 
 def test_import_from_pageserver_small(
     pg_bin: PgBin, neon_env_builder: NeonEnvBuilder, test_output_dir: Path

test_runner/regress/test_neon_local_cli.py

@@ -59,3 +59,5 @@ def test_neon_two_primary_endpoints_fail(
     env.neon_cli.endpoint_stop("ep1")
     # ep1 is stopped so create ep2 will succeed
     env.neon_cli.endpoint_start("ep2")
+    # cleanup
+    env.neon_cli.endpoint_stop("ep2")