PowerShell · iSazonov · Jul 7, 2021 · Oct 26, 2020 · Nov 7, 2020 · Nov 9, 2020
diff --git a/.globalconfig b/.globalconfig
@@ -1259,7 +1259,7 @@ dotnet_diagnostic.IDE0043.severity = silent
 
 # IDE0044: MakeFieldReadonly
 # https://docs.microsoft.com/dotnet/fundamentals/code-analysis/style-rules/ide0044
-dotnet_diagnostic.IDE0044.severity = silent
+dotnet_diagnostic.IDE0044.severity = warning
 
 # IDE0045: UseConditionalExpressionForAssignment
 # https://docs.microsoft.com/dotnet/fundamentals/code-analysis/style-rules/ide0045

diff --git a/src/System.Management.Automation/CoreCLR/CorePsPlatform.cs b/src/System.Management.Automation/CoreCLR/CorePsPlatform.cs
@@ -622,8 +622,8 @@ internal static class NativeMethods
         /// <summary>Unix specific implementations of required functionality.</summary>
         internal static class Unix
         {
-            private static Dictionary<int, string> usernameCache = new();
-            private static Dictionary<int, string> groupnameCache = new();
+            private static readonly Dictionary<int, string> usernameCache = new();
+            private static readonly Dictionary<int, string> groupnameCache = new();
 
             /// <summary>The type of a Unix file system item.</summary>
             public enum ItemType
@@ -755,7 +755,7 @@ public class CommonStat
                 private const char CanExecute = 'x';
 
                 // helper for getting unix mode
-                private Dictionary<StatMask, char> modeMap = new()
+                private readonly Dictionary<StatMask, char> modeMap = new()
                 {
                         { StatMask.OwnerRead, CanRead },
                         { StatMask.OwnerWrite, CanWrite },
@@ -768,7 +768,7 @@ public class CommonStat
                         { StatMask.OtherExecute, CanExecute },
                 };
 
-                private StatMask[] permissions = new StatMask[]
+                private readonly StatMask[] permissions = new StatMask[]
                 {
                     StatMask.OwnerRead,
                     StatMask.OwnerWrite,
@@ -782,7 +782,7 @@ public class CommonStat
                 };
 
                 // The item type and the character representation for the first element in the stat string
-                private Dictionary<ItemType, char> itemTypeTable = new()
+                private readonly Dictionary<ItemType, char> itemTypeTable = new()
                 {
                     { ItemType.BlockDevice, 'b' },
                     { ItemType.CharacterDevice, 'c' },

diff --git a/src/System.Management.Automation/DscSupport/CimDSCParser.cs b/src/System.Management.Automation/DscSupport/CimDSCParser.cs
@@ -317,8 +317,8 @@ public override object Transform(EngineIntrinsics engineIntrinsics, object input
     /// </summary>
     internal class CimDSCParser
     {
-        private CimMofDeserializer _deserializer;
-        private CimMofDeserializer.OnClassNeeded _onClassNeeded;
+        private readonly CimMofDeserializer _deserializer;
+        private readonly CimMofDeserializer.OnClassNeeded _onClassNeeded;
 
         /// <summary>
         /// </summary>
@@ -529,7 +529,7 @@ public static class DscClassCache
 
         private const string reservedProperties = "^(Require|Trigger|Notify|Before|After|Subscribe)$";
 
-        private static PSTraceSource s_tracer = PSTraceSource.GetTracer("DSC", "DSC Class Cache");
+        private static readonly PSTraceSource s_tracer = PSTraceSource.GetTracer("DSC", "DSC Class Cache");
 
         // Constants for items in the module qualified name (Module\Version\ClassName)
         private const int IndexModuleName = 0;

diff --git a/src/System.Management.Automation/GlobalSuppressions.cs b/src/System.Management.Automation/GlobalSuppressions.cs
@@ -0,0 +1,8 @@
+using System.Diagnostics.CodeAnalysis;
+
+[assembly: SuppressMessage(
+    "Style",
+    "IDE0044:Add readonly modifier",
+    Justification = "see src/System.Management.Automation/engine/ComInterop/README.md",
+    Scope = "NamespaceAndDescendants",
+    Target = "~N:System.Management.Automation.ComInterop")]
diff --git a/src/System.Management.Automation/cimSupport/cmdletization/EnumWriter.cs b/src/System.Management.Automation/cimSupport/cmdletization/EnumWriter.cs
@@ -23,8 +23,8 @@ private static ModuleBuilder CreateModuleBuilder()
             return mb;
         }
 
-        private static Lazy<ModuleBuilder> s_moduleBuilder = new(CreateModuleBuilder, isThreadSafe: true);
-        private static object s_moduleBuilderUsageLock = new();
+        private static readonly Lazy<ModuleBuilder> s_moduleBuilder = new(CreateModuleBuilder, isThreadSafe: true);
+        private static readonly object s_moduleBuilderUsageLock = new();
 
         internal static string GetEnumFullName(EnumMetadataEnum enumMetadata)
         {

diff --git a/src/System.Management.Automation/cimSupport/cmdletization/ScriptWriter.cs b/src/System.Management.Automation/cimSupport/cmdletization/ScriptWriter.cs
@@ -386,7 +386,7 @@ private List<string> GetMethodParameterSets(StaticCmdletMetadata staticCmdlet)
             return new List<string>(parameterSetNames.Keys);
         }
 
-        private Dictionary<CommonMethodMetadata, int> _staticMethodMetadataToUniqueId = new();
+        private readonly Dictionary<CommonMethodMetadata, int> _staticMethodMetadataToUniqueId = new();
 
         private string GetMethodParameterSet(CommonMethodMetadata methodMetadata)
         {
@@ -2100,7 +2100,7 @@ private void WriteGetCmdlet(TextWriter output)
                 /* 1 */ CodeGeneration.EscapeSingleQuotedStringContent(commandMetadata.Name));
         }
 
-        private static object s_enumCompilationLock = new();
+        private static readonly object s_enumCompilationLock = new();
 
         private static void CompileEnum(EnumMetadataEnum enumMetadata)
         {

diff --git a/src/System.Management.Automation/engine/InternalCommands.cs b/src/System.Management.Automation/engine/InternalCommands.cs
@@ -385,7 +385,7 @@ public void Dispose()
         // TODO: Look into using SessionState.Internal.GetAliasTable() to find all user created aliases.
         //       But update Alias command logic to maintain reverse table that lists all aliases mapping
         //       to a single command definition, for performance.
-        private static string[] forEachNames = new string[]
+        private static readonly string[] forEachNames = new string[]
         {
             "ForEach-Object",
             "foreach",

diff --git a/src/System.Management.Automation/engine/NativeCommandParameterBinder.cs b/src/System.Management.Automation/engine/NativeCommandParameterBinder.cs
@@ -182,7 +182,7 @@ internal void AddToArgumentList(CommandParameterInternal parameter, string argum
             }
         }
 
-        private List<string> _argumentList = new List<string>();
+        private readonly List<string> _argumentList = new List<string>();
 
         /// <summary>
         /// Gets a value indicating whether to use an ArgumentList or string for arguments when invoking a native executable.

diff --git a/src/System.Management.Automation/engine/interpreter/InstructionList.cs b/src/System.Management.Automation/engine/interpreter/InstructionList.cs
@@ -95,7 +95,9 @@ internal sealed class InstructionList
         private List<BranchLabel> _labels;
 
         // list of (instruction index, cookie) sorted by instruction index:
+#pragma warning disable IDE0044 // Add readonly modifier
         private List<KeyValuePair<int, object>> _debugCookies = null;
+#pragma warning restore IDE0044 // Variable is assigned when DEBUG is defined.
 
         #region Debug View
 

@@ -19,7 +19,9 @@ internal class HyperVSocketEndPoint : EndPoint
 
         private readonly System.Net.Sockets.AddressFamily _addressFamily;
         private Guid _vmId;
+#pragma warning disable IDE0044
         private Guid _serviceId;
+#pragma warning restore IDE0044 // https://github.com/PowerShell/PowerShell/issues/13995
 
         public const System.Net.Sockets.AddressFamily AF_HYPERV = (System.Net.Sockets.AddressFamily)34;
         public const int HYPERV_SOCK_ADDR_SIZE = 36;

diff --git a/src/System.Management.Automation/logging/MshLog.cs b/src/System.Management.Automation/logging/MshLog.cs
@@ -60,13 +60,13 @@ internal static class MshLog
         /// The value of this dictionary is never empty. A value of type DummyProvider means
         /// no logging.
         /// </summary>
-        private static ConcurrentDictionary<string, Collection<LogProvider>> s_logProviders =
+        private static readonly ConcurrentDictionary<string, Collection<LogProvider>> s_logProviders =
             new ConcurrentDictionary<string, Collection<LogProvider>>();
 
         private const string _crimsonLogProviderAssemblyName = "MshCrimsonLog";
         private const string _crimsonLogProviderTypeName = "System.Management.Automation.Logging.CrimsonLogProvider";
 
-        private static Collection<string> s_ignoredCommands = new Collection<string>();
+        private static readonly Collection<string> s_ignoredCommands = new Collection<string>();
 
         /// <summary>
         /// Static constructor.

diff --git a/src/System.Management.Automation/security/CatalogHelper.cs b/src/System.Management.Automation/security/CatalogHelper.cs
@@ -68,14 +68,14 @@ public class CatalogInformation
     internal static class CatalogHelper
     {
         // Catalog Version is (0X100 = 256) for Catalog Version 1
-        private static int catalogVersion1 = 256;
+        private const int catalogVersion1 = 256;
 
         // Catalog Version is (0X200 = 512) for Catalog Version 2
-        private static int catalogVersion2 = 512;
+        private const int catalogVersion2 = 512;
 
         // Hash Algorithms supported by Windows Catalog
-        private static string HashAlgorithmSHA1 = "SHA1";
-        private static string HashAlgorithmSHA256 = "SHA256";
+        private const string HashAlgorithmSHA1 = "SHA1";
+        private const string HashAlgorithmSHA256 = "SHA256";
         private static PSCmdlet _cmdlet = null;
 
         /// <summary>

diff --git a/src/System.Management.Automation/security/SecurityManager.cs b/src/System.Management.Automation/security/SecurityManager.cs
@@ -69,7 +69,7 @@ internal enum RunPromptDecision
         private ExecutionPolicy _executionPolicy;
 
         // shellId supplied by runspace configuration
-        private string _shellId;
+        private readonly string _shellId;
 
         /// <summary>
         /// Initializes a new instance of the PSAuthorizationManager

diff --git a/src/System.Management.Automation/security/SecuritySupport.cs b/src/System.Management.Automation/security/SecuritySupport.cs
@@ -995,7 +995,7 @@ public CmsMessageRecipient(string identifier)
             this.Certificates = new X509Certificate2Collection();
         }
 
-        private string _identifier = null;
+        private readonly string _identifier;
 
         /// <summary>
         /// Creates an instance of the CmsMessageRecipient class.
@@ -1007,7 +1007,7 @@ public CmsMessageRecipient(X509Certificate2 certificate)
             this.Certificates = new X509Certificate2Collection();
         }
 
-        private X509Certificate2 _pendingCertificate = null;
+        private readonly X509Certificate2 _pendingCertificate;
 
         /// <summary>
         /// Gets the certificate associated with this recipient.
@@ -1499,7 +1499,7 @@ internal static void CurrentDomain_ProcessExit(object sender, EventArgs e)
         private static IntPtr s_amsiSession = IntPtr.Zero;
 
         private static bool s_amsiInitFailed = false;
-        private static object s_amsiLockObject = new object();
+        private static readonly object s_amsiLockObject = new object();
 
         /// <summary>
         /// Reset the AMSI session (used to track related script invocations)

diff --git a/src/System.Management.Automation/security/nativeMethods.cs b/src/System.Management.Automation/security/nativeMethods.cs
@@ -1088,36 +1088,38 @@ internal static DWORD DestroyWintrustDataStruct(WINTRUST_DATA wtd)
         [StructLayout(LayoutKind.Sequential)]
         internal struct CRYPT_PROVIDER_CERT
         {
+#pragma warning disable IDE0044
             private DWORD _cbStruct;
+#pragma warning restore IDE0044
             internal IntPtr pCert; // PCCERT_CONTEXT
-            private BOOL _fCommercial;
-            private BOOL _fTrustedRoot;
-            private BOOL _fSelfSigned;
-            private BOOL _fTestCert;
-            private DWORD _dwRevokedReason;
-            private DWORD _dwConfidence;
-            private DWORD _dwError;
-            private IntPtr _pTrustListContext; // CTL_CONTEXT*
-            private BOOL _fTrustListSignerCert;
-            private IntPtr _pCtlContext; // PCCTL_CONTEXT
-            private DWORD _dwCtlError;
-            private BOOL _fIsCyclic;
-            private IntPtr _pChainElement; // PCERT_CHAIN_ELEMENT
+            private readonly BOOL _fCommercial;
+            private readonly BOOL _fTrustedRoot;
+            private readonly BOOL _fSelfSigned;
+            private readonly BOOL _fTestCert;
+            private readonly DWORD _dwRevokedReason;
+            private readonly DWORD _dwConfidence;
+            private readonly DWORD _dwError;
+            private readonly IntPtr _pTrustListContext; // CTL_CONTEXT*
+            private readonly BOOL _fTrustListSignerCert;
+            private readonly IntPtr _pCtlContext; // PCCTL_CONTEXT
+            private readonly DWORD _dwCtlError;
+            private readonly BOOL _fIsCyclic;
+            private readonly IntPtr _pChainElement; // PCERT_CHAIN_ELEMENT
         }
 
         [StructLayout(LayoutKind.Sequential)]
         internal struct CRYPT_PROVIDER_SGNR
         {
-            private DWORD _cbStruct;
+            private readonly DWORD _cbStruct;
             private FILETIME _sftVerifyAsOf;
-            private DWORD _csCertChain;
-            private IntPtr _pasCertChain; // CRYPT_PROVIDER_CERT*
-            private DWORD _dwSignerType;
-            private IntPtr _psSigner; // CMSG_SIGNER_INFO*
-            private DWORD _dwError;
+            private readonly DWORD _csCertChain;
+            private readonly IntPtr _pasCertChain; // CRYPT_PROVIDER_CERT*
+            private readonly DWORD _dwSignerType;
+            private readonly IntPtr _psSigner; // CMSG_SIGNER_INFO*
+            private readonly DWORD _dwError;
             internal DWORD csCounterSigners;
             internal IntPtr pasCounterSigners; // CRYPT_PROVIDER_SGNR*
-            private IntPtr _pChainContext; // PCCERT_CHAIN_CONTEXT
+            private readonly IntPtr _pChainContext; // PCCERT_CHAIN_CONTEXT
         }
 
         [DllImport("wintrust.dll", SetLastError = true, CharSet = CharSet.Unicode)]
@@ -1993,33 +1995,33 @@ internal struct CRYPTCATMEMBER
         [StructLayout(LayoutKind.Sequential)]
         internal struct CRYPTCATATTRIBUTE
         {
-            private DWORD _cbStruct;
+            private readonly DWORD _cbStruct;
 
             [MarshalAs(UnmanagedType.LPWStr)]
             internal string pwszReferenceTag;
 
-            private DWORD _dwAttrTypeAndAction;
+            private readonly DWORD _dwAttrTypeAndAction;
             internal DWORD cbValue;
             internal System.IntPtr pbValue;
-            private DWORD _dwReserved;
+            private readonly DWORD _dwReserved;
         }
 
         [StructLayout(LayoutKind.Sequential)]
         internal struct CRYPTCATSTORE
         {
-            private DWORD _cbStruct;
+            private readonly DWORD _cbStruct;
             internal DWORD dwPublicVersion;
 
             [MarshalAs(UnmanagedType.LPWStr)]
             internal string pwszP7File;
 
-            private IntPtr _hProv;
-            private DWORD _dwEncodingType;
-            private DWORD _fdwStoreFlags;
-            private IntPtr _hReserved;
-            private IntPtr _hAttrs;
-            private IntPtr _hCryptMsg;
-            private IntPtr _hSorted;
+            private readonly IntPtr _hProv;
+            private readonly DWORD _dwEncodingType;
+            private readonly DWORD _fdwStoreFlags;
+            private readonly IntPtr _hReserved;
+            private readonly IntPtr _hAttrs;
+            private readonly IntPtr _hCryptMsg;
+            private readonly IntPtr _hSorted;
         }
 
         [DllImport("wintrust.dll", CharSet = CharSet.Unicode)]

@@ -68,7 +68,7 @@ public static SystemEnforcementMode GetSystemLockdownPolicy()
             return s_systemLockdownPolicy.Value;
         }
 
-        private static object s_systemLockdownPolicyLock = new object();
+        private static readonly object s_systemLockdownPolicyLock = new object();
         private static SystemEnforcementMode? s_systemLockdownPolicy = null;
         private static bool s_allowDebugOverridePolicy = false;
 

diff --git a/src/System.Management.Automation/singleshell/config/MshConsoleLoadException.cs b/src/System.Management.Automation/singleshell/config/MshConsoleLoadException.cs
@@ -86,7 +86,7 @@ private void CreateErrorRecord()
             _errorRecord = new ErrorRecord(new ParentContainsErrorRecordException(this), "ConsoleLoadFailure", ErrorCategory.ResourceUnavailable, null);
         }
 
-        private Collection<PSSnapInException> _PSSnapInExceptions = new Collection<PSSnapInException>();
+        private readonly Collection<PSSnapInException> _PSSnapInExceptions = new Collection<PSSnapInException>();
 
         internal Collection<PSSnapInException> PSSnapInExceptions
         {

diff --git a/src/System.Management.Automation/singleshell/config/MshSnapinInfo.cs b/src/System.Management.Automation/singleshell/config/MshSnapinInfo.cs
@@ -262,8 +262,8 @@ internal string AbsoluteModulePath
         /// </summary>
         public Collection<string> Formats { get; }
 
-        private string _descriptionIndirect;
-        private string _descriptionFallback = string.Empty;
+        private readonly string _descriptionIndirect;
+        private readonly string _descriptionFallback = string.Empty;
         private string _description;
         /// <summary>
         /// Description of mshsnapin.
@@ -281,8 +281,8 @@ public string Description
             }
         }
 
-        private string _vendorIndirect;
-        private string _vendorFallback = string.Empty;
+        private readonly string _vendorIndirect;
+        private readonly string _vendorFallback = string.Empty;
         private string _vendor;
         /// <summary>
         /// Vendor of mshsnapin.
@@ -1335,10 +1335,10 @@ private static IList<DefaultPSSnapInInformation> DefaultMshSnapins
         }
 
         private static IList<DefaultPSSnapInInformation> s_defaultMshSnapins = null;
-        private static object s_syncObject = new object();
+        private static readonly object s_syncObject = new object();
 
         #endregion
 
-        private static PSTraceSource s_mshsnapinTracer = PSTraceSource.GetTracer("MshSnapinLoadUnload", "Loading and unloading mshsnapins", false);
+        private static readonly PSTraceSource s_mshsnapinTracer = PSTraceSource.GetTracer("MshSnapinLoadUnload", "Loading and unloading mshsnapins", false);
     }
 }
diff --git a/src/System.Management.Automation/singleshell/config/MshSnapinLoadException.cs b/src/System.Management.Automation/singleshell/config/MshSnapinLoadException.cs
@@ -116,7 +116,7 @@ private void CreateErrorRecord()
             }
         }
 
-        private bool _warning = false;
+        private readonly bool _warning = false;
 
         private ErrorRecord _errorRecord;
         private bool _isErrorRecordOriginallyNull;
@@ -146,8 +146,8 @@ public override ErrorRecord ErrorRecord
             }
         }
 
-        private string _PSSnapin = string.Empty;
-        private string _reason = string.Empty;
+        private readonly string _PSSnapin = string.Empty;
+        private readonly string _reason = string.Empty;
 
         /// <summary>
         /// Gets message for this exception.

diff --git a/src/System.Management.Automation/utils/tracing/PSEtwLogProvider.cs b/src/System.Management.Automation/utils/tracing/PSEtwLogProvider.cs
@@ -17,7 +17,7 @@ internal class PSEtwLogProvider : LogProvider
     {
         private static readonly EventProvider etwProvider;
         internal static readonly Guid ProviderGuid = new Guid("F90714A8-5509-434A-BF6D-B1624C8A19A2");
-        private static EventDescriptor _xferEventDescriptor = new EventDescriptor(0x1f05, 0x1, 0x11, 0x5, 0x14, 0x0, (long)0x4000000000000000);
+        private static readonly EventDescriptor _xferEventDescriptor = new EventDescriptor(0x1f05, 0x1, 0x11, 0x5, 0x14, 0x0, (long)0x4000000000000000);
 
         /// <summary>
         /// Class constructor.