From a6db102cd2ee02f45ced163b2ba73049fd73f0ca Mon Sep 17 00:00:00 2001
From: AR-May <67507805+AR-May@users.noreply.github.com>
Date: Tue, 20 Jul 2021 18:04:35 +0200
Subject: [PATCH] Remove extra lock in ProjectRootElementCache.Get for unit
 tests.

---
 .../Evaluation/ProjectRootElementCache.cs     | 35 +++++++++----------
 1 file changed, 16 insertions(+), 19 deletions(-)

diff --git a/src/Build/Evaluation/ProjectRootElementCache.cs b/src/Build/Evaluation/ProjectRootElementCache.cs
index 921a5b39f14..bf519b82224 100644
--- a/src/Build/Evaluation/ProjectRootElementCache.cs
+++ b/src/Build/Evaluation/ProjectRootElementCache.cs
@@ -157,26 +157,23 @@ private bool IsInvalidEntry(string projectFile, ProjectRootElement projectRootEl
                     }
                     else if (!String.IsNullOrEmpty(Environment.GetEnvironmentVariable("MSBUILDCACHECHECKFILECONTENT")))
                     {
-                        lock (_locker)
+                        // QA tests run too fast for the timestamp check to work. This environment variable is for their
+                        // use: it checks the file content as well as the timestamp. That's better than completely disabling
+                        // the cache as we get test coverage of the rest of the cache code.
+                        XmlDocument document = new XmlDocument();
+                        document.PreserveWhitespace = projectRootElement.XmlDocument.PreserveWhitespace;
+
+                        using (var xtr = XmlReaderExtension.Create(projectRootElement.FullPath, projectRootElement.ProjectRootElementCache.LoadProjectsReadOnly))
+                        {
+                            document.Load(xtr.Reader);
+                        }
+
+                        string diskContent = document.OuterXml;
+                        string cacheContent = projectRootElement.XmlDocument.OuterXml;
+
+                        if (diskContent != cacheContent)
                         {
-                            // QA tests run too fast for the timestamp check to work. This environment variable is for their
-                            // use: it checks the file content as well as the timestamp. That's better than completely disabling
-                            // the cache as we get test coverage of the rest of the cache code.
-                            XmlDocument document = new XmlDocument();
-                            document.PreserveWhitespace = projectRootElement.XmlDocument.PreserveWhitespace;
-
-                            using (var xtr = XmlReaderExtension.Create(projectRootElement.FullPath, projectRootElement.ProjectRootElementCache.LoadProjectsReadOnly))
-                            {
-                                document.Load(xtr.Reader);
-                            }
-
-                            string diskContent = document.OuterXml;
-                            string cacheContent = projectRootElement.XmlDocument.OuterXml;
-
-                            if (diskContent != cacheContent)
-                            {
-                                return true;
-                            }
+                            return true;
                         }
                     }
                 }