From 2510f246d37e256e3b87ef7a5c0d926f7db301b3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Michal=20Strehovsk=C3=BD?=
 <MichalStrehovsky@users.noreply.github.com>
Date: Tue, 21 Apr 2026 21:43:41 +0900
Subject: [PATCH] Fix trimming warnings in System.Diagnostics.Process tests

Replace obj.GetType().GetField(...) and assembly.GetType(...) with
Type.GetType("FullName, AssemblyName") patterns that the trim
analyzer can statically analyze. Re-enable the trim analyzer in the
test project.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
---
 .../tests/ProcessStartInfoTests.cs                          | 3 +--
 .../System.Diagnostics.Process/tests/ProcessTests.Unix.cs   | 6 +++---
 .../tests/System.Diagnostics.Process.Tests.csproj           | 2 --
 3 files changed, 4 insertions(+), 7 deletions(-)

diff --git a/src/libraries/System.Diagnostics.Process/tests/ProcessStartInfoTests.cs b/src/libraries/System.Diagnostics.Process/tests/ProcessStartInfoTests.cs
index ecd5a5b3b0bf7e..ba1eb8445aa33c 100644
--- a/src/libraries/System.Diagnostics.Process/tests/ProcessStartInfoTests.cs
+++ b/src/libraries/System.Diagnostics.Process/tests/ProcessStartInfoTests.cs
@@ -391,8 +391,7 @@ private string[] ExecuteProcessAndReturnParsedOutput(Dictionary<string, string>
             // To mimic this behaviour, we can't use Environment.SetEnvironmentVariable here as it's case-insensitive on Windows.
             // We also can't use p.StartInfo.Environment as it's comparer is set to OrdinalIgnoreCAse.
             // But we can overwrite it using reflection to mimic the CreateProcess behaviour and avoid having this test call CreateProcess directly.
-            p.StartInfo.Environment
-                .GetType()
+            Type.GetType("System.Collections.Specialized.DictionaryWrapper, System.Diagnostics.Process")!
                 .GetField("_contents", Reflection.BindingFlags.NonPublic | Reflection.BindingFlags.Instance)
                 .SetValue(p.StartInfo.Environment, envVars);
 
diff --git a/src/libraries/System.Diagnostics.Process/tests/ProcessTests.Unix.cs b/src/libraries/System.Diagnostics.Process/tests/ProcessTests.Unix.cs
index b4588bd89eca29..1e7399eba08ae0 100644
--- a/src/libraries/System.Diagnostics.Process/tests/ProcessTests.Unix.cs
+++ b/src/libraries/System.Diagnostics.Process/tests/ProcessTests.Unix.cs
@@ -960,8 +960,7 @@ Process CreateNonChildProcess()
 
         private static IDictionary GetWaitStateDictionary(bool childDictionary)
         {
-            Assembly assembly = typeof(Process).Assembly;
-            Type waitStateType = assembly.GetType("System.Diagnostics.ProcessWaitState");
+            Type waitStateType = Type.GetType("System.Diagnostics.ProcessWaitState, System.Diagnostics.Process")!;
             FieldInfo dictionaryField = waitStateType.GetField(childDictionary ? "s_childProcessWaitStates" : "s_processWaitStates", BindingFlags.NonPublic | BindingFlags.Static);
             return (IDictionary)dictionaryField.GetValue(null);
         }
@@ -974,7 +973,8 @@ private static object GetProcessWaitState(Process p)
 
         private static int GetWaitStateReferenceCount(object waitState)
         {
-            FieldInfo referenCountField = waitState.GetType().GetField("_outstandingRefCount", BindingFlags.NonPublic | BindingFlags.Instance);
+            FieldInfo referenCountField = Type.GetType("System.Diagnostics.ProcessWaitState, System.Diagnostics.Process")!
+                .GetField("_outstandingRefCount", BindingFlags.NonPublic | BindingFlags.Instance);
             return (int)referenCountField.GetValue(waitState);
         }
 
diff --git a/src/libraries/System.Diagnostics.Process/tests/System.Diagnostics.Process.Tests.csproj b/src/libraries/System.Diagnostics.Process/tests/System.Diagnostics.Process.Tests.csproj
index b967b041ab6d21..ee26045c6cbf20 100644
--- a/src/libraries/System.Diagnostics.Process/tests/System.Diagnostics.Process.Tests.csproj
+++ b/src/libraries/System.Diagnostics.Process/tests/System.Diagnostics.Process.Tests.csproj
@@ -5,8 +5,6 @@
     <IncludeRemoteExecutor>true</IncludeRemoteExecutor>
     <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-unix;$(NetCoreAppCurrent)-browser;$(NetCoreAppCurrent)-android;$(NetCoreAppCurrent)-maccatalyst</TargetFrameworks>
     <IgnoreForCI Condition="'$(TargetOS)' == 'browser'">true</IgnoreForCI>
-    <!-- https://github.com/dotnet/runtime/issues/126862 -->
-    <EnableTrimAnalyzer>false</EnableTrimAnalyzer>
   </PropertyGroup>
   <!-- DesignTimeBuild requires all the TargetFramework Derived Properties to not be present in the first property group. -->
   <PropertyGroup>