From 63a82dccb2b606a96e7428b5d396cd9e73cfe0b9 Mon Sep 17 00:00:00 2001
From: Thad House <ThadHouse@users.noreply.github.com>
Date: Thu, 7 May 2026 09:58:14 -0700
Subject: [PATCH] [wpilib] Don't do wait on init for ExHub in sim (#8865)

Closes #8859
---
 .../cpp/hardware/expansionhub/ExpansionHub.cpp      | 13 ++++++++-----
 .../wpilib/hardware/expansionhub/ExpansionHub.java  | 13 ++++++++-----
 2 files changed, 16 insertions(+), 10 deletions(-)

diff --git a/wpilibc/src/main/native/cpp/hardware/expansionhub/ExpansionHub.cpp b/wpilibc/src/main/native/cpp/hardware/expansionhub/ExpansionHub.cpp
index a2c5fed690..cb3d42bf17 100644
--- a/wpilibc/src/main/native/cpp/hardware/expansionhub/ExpansionHub.cpp
+++ b/wpilibc/src/main/native/cpp/hardware/expansionhub/ExpansionHub.cpp
@@ -8,6 +8,7 @@
 #include <memory>
 #include <thread>
 
+#include "wpi/framework/RobotBase.hpp"
 #include "wpi/hal/UsageReporting.hpp"
 #include "wpi/hardware/expansionhub/ExpansionHubCRServo.hpp"
 #include "wpi/hardware/expansionhub/ExpansionHubMotor.hpp"
@@ -33,12 +34,14 @@ class ExpansionHub::DataStore {
 
     // Wait up to half a second for connected to come up, using a poll loop to
     // ensure we don't block.
-    auto startTime = Timer::GetMonotonicTimestamp();
-    while (Timer::GetMonotonicTimestamp() - startTime < 0.5_s) {
-      if (m_hubConnectedSubscriber.Get(false)) {
-        break;
+    if constexpr (RobotBase::IsReal()) {
+      auto startTime = Timer::GetMonotonicTimestamp();
+      while (Timer::GetMonotonicTimestamp() - startTime < 0.5_s) {
+        if (m_hubConnectedSubscriber.Get(false)) {
+          break;
+        }
+        std::this_thread::sleep_for(std::chrono::milliseconds(10));
       }
-      std::this_thread::sleep_for(std::chrono::milliseconds(10));
     }
   }
 
diff --git a/wpilibj/src/main/java/org/wpilib/hardware/expansionhub/ExpansionHub.java b/wpilibj/src/main/java/org/wpilib/hardware/expansionhub/ExpansionHub.java
index 4883d756cf..f7e931aa26 100644
--- a/wpilibj/src/main/java/org/wpilib/hardware/expansionhub/ExpansionHub.java
+++ b/wpilibj/src/main/java/org/wpilib/hardware/expansionhub/ExpansionHub.java
@@ -4,6 +4,7 @@
 
 package org.wpilib.hardware.expansionhub;
 
+import org.wpilib.framework.RobotBase;
 import org.wpilib.hardware.hal.HAL;
 import org.wpilib.networktables.BooleanSubscriber;
 import org.wpilib.networktables.NetworkTableInstance;
@@ -32,12 +33,14 @@ public class ExpansionHub implements AutoCloseable {
 
       // Wait up to half a second for connected to come up, using a poll loop to
       // ensure we don't block.
-      double startTime = Timer.getMonotonicTimestamp();
-      while (Timer.getMonotonicTimestamp() - startTime < 0.5) {
-        if (m_hubConnectedSubscriber.get(false)) {
-          break;
+      if (RobotBase.isReal()) {
+        double startTime = Timer.getMonotonicTimestamp();
+        while (Timer.getMonotonicTimestamp() - startTime < 0.5) {
+          if (m_hubConnectedSubscriber.get(false)) {
+            break;
+          }
+          Timer.delay(0.01);
         }
-        Timer.delay(0.01);
       }
     }