add a test for testing user

drivers/rawexec/driver_unix_test.go

@@ -339,6 +339,45 @@ func TestRawExec_ExecTaskStreaming(t *testing.T) {
 
 }
 
+func TestRawExec_ExecTaskStreaming_User(t *testing.T) {
+	t.Parallel()
+	if runtime.GOOS != "linux" {
+		t.Skip("skip, requires running on Linux for testing custom user setting")
+	}
+
+	d := newEnabledRawExecDriver(t)
+	harness := dtestutil.NewDriverHarness(t, d)
+	defer harness.Kill()
+
+	task := &drivers.TaskConfig{
+		ID:   uuid.Generate(),
+		Name: "sleep",
+		User: "nobody",
+	}
+
+	cleanup := harness.MkAllocDir(task, false)
+	defer cleanup()
+
+	err := os.Chmod(task.AllocDir, 0777)
+	require.NoError(t, err)
+
+	tc := &TaskConfig{
+		Command: "/bin/sleep",
+		Args:    []string{"9000"},
+	}
+	require.NoError(t, task.EncodeConcreteDriverConfig(&tc))
+	testtask.SetTaskConfigEnv(task)
+
+	_, _, err = harness.StartTask(task)
+	require.NoError(t, err)
+	defer d.DestroyTask(task.ID, true)
+
+	code, stdout, stderr := dtestutil.ExecTask(t, harness, task.ID, "whoami", false, "")
+	require.Zero(t, code)
+	require.Empty(t, stderr)
+	require.Contains(t, stdout, "nobody")
+}
+
 func TestRawExecDriver_NoCgroup(t *testing.T) {
 	t.Parallel()
 	if runtime.GOOS != "linux" {

plugins/drivers/testutils/exec_testing.go

@@ -208,6 +208,11 @@ func TestExecFSIsolation(t *testing.T, driver *DriverHarness, taskID string) {
 	})
 }
 
+func ExecTask(t *testing.T, driver *DriverHarness, taskID string, cmd string, tty bool, stdin string) (exitCode int, stdout, stderr string) {
+	r := execTask(t, driver, taskID, cmd, tty, stdin)
+	return r.exitCode, r.stdout, r.stderr
+}
+
 func execTask(t *testing.T, driver *DriverHarness, taskID string, cmd string, tty bool, stdin string) execResult {
 	stream := newTestExecStream(t, tty, stdin)