From 73e6405b3f20096769284b830324e0f5ae134346 Mon Sep 17 00:00:00 2001
From: David Burns <david.burns@theautomatedtester.co.uk>
Date: Thu, 5 Mar 2020 10:14:58 +0000
Subject: [PATCH] Perform null check when calling Start on DriverService
 (#8083)

* Perform null check when calling Start on DriverService

* Updates documentation

Co-authored-by: David Burns <david.burns@theautomatedtester.co.uk>
---
 dotnet/src/webdriver/DriverService.cs | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/dotnet/src/webdriver/DriverService.cs b/dotnet/src/webdriver/DriverService.cs
index 08c3468b78d58..fb39a3397b4cd 100644
--- a/dotnet/src/webdriver/DriverService.cs
+++ b/dotnet/src/webdriver/DriverService.cs
@@ -250,11 +250,14 @@ public void Dispose()
         }
 
         /// <summary>
-        /// Starts the DriverService.
+        /// Starts the DriverService if it is not already running.
         /// </summary>
         [SecurityPermission(SecurityAction.Demand)]
         public void Start()
         {
+            if(this.driverServiceProcess != null)
+                return;
+
             this.driverServiceProcess = new Process();
             this.driverServiceProcess.StartInfo.FileName = Path.Combine(this.driverServicePath, this.driverServiceExecutableName);
             this.driverServiceProcess.StartInfo.Arguments = this.CommandLineArguments;