From d01bb92ed11ba5584876c2e16549bd3b6461df23 Mon Sep 17 00:00:00 2001
From: Daniel Petrov <daniel221569@gmail.com>
Date: Thu, 14 Oct 2021 19:09:49 +0200
Subject: [PATCH] Remove extra call to PropertyInfo.GetValue(object)

Fix #52905
---
 .../src/ConfigurationBinder.cs                | 10 ++++------
 .../tests/ConfigurationBinderTests.cs         | 19 +++++++++++++++++++
 2 files changed, 23 insertions(+), 6 deletions(-)

diff --git a/src/libraries/Microsoft.Extensions.Configuration.Binder/src/ConfigurationBinder.cs b/src/libraries/Microsoft.Extensions.Configuration.Binder/src/ConfigurationBinder.cs
index f13edb1872ebe..2cbcfbb1c089e 100644
--- a/src/libraries/Microsoft.Extensions.Configuration.Binder/src/ConfigurationBinder.cs
+++ b/src/libraries/Microsoft.Extensions.Configuration.Binder/src/ConfigurationBinder.cs
@@ -248,19 +248,17 @@ private static void BindProperty(PropertyInfo property, object instance, IConfig
                 return;
             }
 
-            object propertyValue = property.GetValue(instance);
             bool hasSetter = property.SetMethod != null && (property.SetMethod.IsPublic || options.BindNonPublicProperties);
 
-            if (propertyValue == null && !hasSetter)
+            if (!hasSetter)
             {
-                // Property doesn't have a value and we cannot set it so there is no
-                // point in going further down the graph
+                // The property cannot be set so there is no point going further
                 return;
             }
 
-            propertyValue = GetPropertyValue(property, instance, config, options);
+            object propertyValue = GetPropertyValue(property, instance, config, options);
 
-            if (propertyValue != null && hasSetter)
+            if (propertyValue != null)
             {
                 property.SetValue(instance, propertyValue);
             }
diff --git a/src/libraries/Microsoft.Extensions.Configuration.Binder/tests/ConfigurationBinderTests.cs b/src/libraries/Microsoft.Extensions.Configuration.Binder/tests/ConfigurationBinderTests.cs
index c5dbd9d90821a..6629557ce89be 100644
--- a/src/libraries/Microsoft.Extensions.Configuration.Binder/tests/ConfigurationBinderTests.cs
+++ b/src/libraries/Microsoft.Extensions.Configuration.Binder/tests/ConfigurationBinderTests.cs
@@ -117,6 +117,11 @@ public class ByteArrayOptions
             public byte[] MyByteArray { get; set; }
         }
 
+        public class GetterOnlyOptions
+        {
+            public string MyString => throw new NotImplementedException();
+        }
+
         [Fact]
         public void CanBindIConfigurationSection()
         {
@@ -343,6 +348,20 @@ public void ThrowsIfPropertyInConfigMissingInNestedModel()
             Assert.Equal(expectedMessage, ex.Message);
         }
 
+        [Fact]
+        public void DoesNotExecuteGetterIfNoSetter()
+        {
+            var dic = new Dictionary<string, string>
+            {
+                {"MyString", "hello world"}
+            };
+            var configurationBuilder = new ConfigurationBuilder();
+            configurationBuilder.AddInMemoryCollection(dic);
+            var config = configurationBuilder.Build();
+
+            var _ = config.Get<GetterOnlyOptions>();
+        }
+
         [Fact]
         public void GetDefaultsWhenDataDoesNotExist()
         {