From be27171236cb72bf7ebcf82dbc9e2edd0f1b08b7 Mon Sep 17 00:00:00 2001
From: Peter Johnson <johnson.peter@gmail.com>
Date: Tue, 6 Dec 2022 21:14:09 -0800
Subject: [PATCH] [wpilibj] Shuffleboard: Check for null sendable (#4772)

Adding a null sendable to a container could result in a delayed NullPointerException.
---
 .../edu/wpi/first/wpilibj/shuffleboard/ContainerHelper.java    | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/wpilibj/src/main/java/edu/wpi/first/wpilibj/shuffleboard/ContainerHelper.java b/wpilibj/src/main/java/edu/wpi/first/wpilibj/shuffleboard/ContainerHelper.java
index d939059567..a448970273 100644
--- a/wpilibj/src/main/java/edu/wpi/first/wpilibj/shuffleboard/ContainerHelper.java
+++ b/wpilibj/src/main/java/edu/wpi/first/wpilibj/shuffleboard/ContainerHelper.java
@@ -10,6 +10,7 @@ import edu.wpi.first.networktables.NetworkTableType;
 import edu.wpi.first.util.function.FloatSupplier;
 import edu.wpi.first.util.sendable.Sendable;
 import edu.wpi.first.util.sendable.SendableRegistry;
+import edu.wpi.first.wpilibj.util.ErrorMessages;
 import java.util.ArrayList;
 import java.util.HashSet;
 import java.util.LinkedHashMap;
@@ -57,6 +58,7 @@ final class ContainerHelper {
   }
 
   ComplexWidget add(String title, Sendable sendable) {
+    ErrorMessages.requireNonNullParam(sendable, "sendable", "add");
     checkTitle(title);
     ComplexWidget widget = new ComplexWidget(m_container, title, sendable);
     m_components.add(widget);
@@ -64,6 +66,7 @@ final class ContainerHelper {
   }
 
   ComplexWidget add(Sendable sendable) {
+    ErrorMessages.requireNonNullParam(sendable, "sendable", "add");
     String name = SendableRegistry.getName(sendable);
     if (name.isEmpty()) {
       throw new IllegalArgumentException("Sendable must have a name");