Make more progress on IDE0044 ("Make field readonly") (dotnet#82356)

* Make more progress on IDE0044 ("Make field readonly")

* Apply suggestions from code review

Co-authored-by: Jan Kotas <[email protected]>

---------

Co-authored-by: Jan Kotas <[email protected]>

src/coreclr/System.Private.CoreLib/src/System/Diagnostics/EditAndContinueHelper.cs

@@ -14,8 +14,8 @@ namespace System.Diagnostics
 {
     internal sealed class EditAndContinueHelper
     {
-#pragma warning disable CA1823, 169, 414 // field is not used from managed.
+#pragma warning disable CA1823, 169, 414, IDE0044 // field is not used from managed.
         private object? _objectReference;
-#pragma warning restore CA1823, 169, 414
+#pragma warning restore CA1823, 169, 414, IDE0044
     }
 }

src/coreclr/System.Private.CoreLib/src/System/Reflection/Emit/CustomAttributeBuilder.cs

@@ -21,9 +21,9 @@ namespace System.Reflection.Emit
 {
     public class CustomAttributeBuilder
     {
-        internal ConstructorInfo m_con;
-        private object?[] m_constructorArgs;
-        private byte[] m_blob;
+        internal readonly ConstructorInfo m_con;
+        private readonly object?[] m_constructorArgs;
+        private readonly byte[] m_blob;
 
         // public constructor to form the custom attribute with constructor and constructor
         // parameters.

src/coreclr/System.Private.CoreLib/src/System/Reflection/Emit/DynamicILGenerator.cs

@@ -11,7 +11,7 @@ namespace System.Reflection.Emit
     internal sealed class DynamicILGenerator : ILGenerator
     {
         internal DynamicScope m_scope;
-        private int m_methodSigToken;
+        private readonly int m_methodSigToken;
 
         internal DynamicILGenerator(DynamicMethod method, byte[] methodSignature, int size)
             : base(method, size)
@@ -571,13 +571,13 @@ private int GetTokenForSig(byte[] sig)
     internal sealed class DynamicResolver : Resolver
     {
         #region Private Data Members
-        private __ExceptionInfo[]? m_exceptions;
-        private byte[]? m_exceptionHeader;
-        private DynamicMethod m_method;
-        private byte[] m_code;
-        private byte[] m_localSignature;
-        private int m_stackSize;
-        private DynamicScope m_scope;
+        private readonly __ExceptionInfo[]? m_exceptions;
+        private readonly byte[]? m_exceptionHeader;
+        private readonly DynamicMethod m_method;
+        private readonly byte[] m_code;
+        private readonly byte[] m_localSignature;
+        private readonly int m_stackSize;
+        private readonly DynamicScope m_scope;
         #endregion
 
         #region Internal Methods
@@ -857,13 +857,13 @@ internal override void ResolveToken(int token, out IntPtr typeHandle, out IntPtr
     public class DynamicILInfo
     {
         #region Private Data Members
-        private DynamicMethod m_method;
-        private DynamicScope m_scope;
+        private readonly DynamicMethod m_method;
+        private readonly DynamicScope m_scope;
         private byte[] m_exceptions;
         private byte[] m_code;
         private byte[] m_localSignature;
         private int m_maxStackSize;
-        private int m_methodSignature;
+        private readonly int m_methodSignature;
         #endregion
 
         #region Constructor

src/coreclr/System.Private.CoreLib/src/System/Reflection/Emit/LocalBuilder.cs

@@ -6,10 +6,10 @@ namespace System.Reflection.Emit
     public sealed class LocalBuilder : LocalVariableInfo
     {
         #region Private Data Members
-        private int m_localIndex;
-        private Type m_localType;
-        private MethodInfo m_methodBuilder;
-        private bool m_isPinned;
+        private readonly int m_localIndex;
+        private readonly Type m_localType;
+        private readonly MethodInfo m_methodBuilder;
+        private readonly bool m_isPinned;
         #endregion
 
         #region Constructor

src/coreclr/System.Private.CoreLib/src/System/Reflection/Emit/ParameterBuilder.cs

@@ -77,7 +77,7 @@ internal int GetToken()
         private readonly string? _name;
         private readonly int _position;
         private readonly ParameterAttributes _attributes;
-        private RuntimeMethodBuilder _methodBuilder;
-        private int _token;
+        private readonly RuntimeMethodBuilder _methodBuilder;
+        private readonly int _token;
     }
 }

src/coreclr/System.Private.CoreLib/src/System/Reflection/Emit/RuntimeEnumBuilder.cs

@@ -357,6 +357,6 @@ internal RuntimeEnumBuilder(
         [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)]
         internal RuntimeTypeBuilder m_typeBuilder;
 
-        private FieldBuilder m_underlyingField;
+        private readonly FieldBuilder m_underlyingField;
     }
 }

src/coreclr/System.Private.CoreLib/src/System/Reflection/Emit/RuntimeEventBuilder.cs

@@ -98,11 +98,10 @@ protected override void SetCustomAttributeCore(CustomAttributeBuilder customBuil
             customBuilder.CreateCustomAttribute(m_module, m_evToken);
         }
 
-        // These are package private so that TypeBuilder can access them.
-        private string m_name;         // The name of the event
-        private int m_evToken;      // The token of this event
-        private RuntimeModuleBuilder m_module;
-        private EventAttributes m_attributes;
-        private RuntimeTypeBuilder m_type;
+        private readonly string m_name;         // The name of the event
+        private readonly int m_evToken;      // The token of this event
+        private readonly RuntimeModuleBuilder m_module;
+        private readonly EventAttributes m_attributes;
+        private readonly RuntimeTypeBuilder m_type;
     }
 }

src/coreclr/System.Private.CoreLib/src/System/Reflection/Emit/RuntimeFieldBuilder.cs

@@ -9,11 +9,11 @@ namespace System.Reflection.Emit
     internal sealed class RuntimeFieldBuilder : FieldBuilder
     {
         #region Private Data Members
-        private int m_fieldTok;
-        private RuntimeTypeBuilder m_typeBuilder;
-        private string m_fieldName;
-        private FieldAttributes m_Attributes;
-        private Type m_fieldType;
+        private readonly int m_fieldTok;
+        private readonly RuntimeTypeBuilder m_typeBuilder;
+        private readonly string m_fieldName;
+        private readonly FieldAttributes m_Attributes;
+        private readonly Type m_fieldType;
         #endregion
 
         #region Constructor

src/coreclr/System.Private.CoreLib/src/System/Reflection/Emit/RuntimePropertyBuilder.cs

@@ -202,13 +202,13 @@ public override bool IsDefined(Type attributeType, bool inherit)
         public override Type? ReflectedType => m_containingType;
 
         // These are package private so that TypeBuilder can access them.
-        private string m_name; // The name of the property
-        private int m_tkProperty; // The token of this property
-        private RuntimeModuleBuilder m_moduleBuilder;
-        private PropertyAttributes m_attributes; // property's attribute flags
-        private Type m_returnType; // property's return type
+        private readonly string m_name; // The name of the property
+        private readonly int m_tkProperty; // The token of this property
+        private readonly RuntimeModuleBuilder m_moduleBuilder;
+        private readonly PropertyAttributes m_attributes; // property's attribute flags
+        private readonly Type m_returnType; // property's return type
         private MethodInfo? m_getMethod;
         private MethodInfo? m_setMethod;
-        private RuntimeTypeBuilder m_containingType;
+        private readonly RuntimeTypeBuilder m_containingType;
     }
 }

src/coreclr/System.Private.CoreLib/src/System/Reflection/Emit/SymbolMethod.cs

@@ -8,13 +8,13 @@ namespace System.Reflection.Emit
     internal sealed class SymbolMethod : MethodInfo
     {
         #region Private Data Members
-        private ModuleBuilder m_module;
-        private Type m_containingType;
-        private string m_name;
-        private CallingConventions m_callingConvention;
-        private Type m_returnType;
-        private int m_token;
-        private Type[] m_parameterTypes;
+        private readonly ModuleBuilder m_module;
+        private readonly Type m_containingType;
+        private readonly string m_name;
+        private readonly CallingConventions m_callingConvention;
+        private readonly Type m_returnType;
+        private readonly int m_token;
+        private readonly Type[] m_parameterTypes;
         #endregion
 
         #region Constructor

src/coreclr/System.Private.CoreLib/src/System/Reflection/MdFieldInfo.cs

@@ -11,10 +11,10 @@ namespace System.Reflection
     internal sealed unsafe class MdFieldInfo : RuntimeFieldInfo
     {
         #region Private Data Members
-        private int m_tkField;
+        private readonly int m_tkField;
         private string? m_name;
         private RuntimeType? m_fieldType;
-        private FieldAttributes m_fieldAttributes;
+        private readonly FieldAttributes m_fieldAttributes;
         #endregion
 
         #region Constructor

src/coreclr/System.Private.CoreLib/src/System/Reflection/MdImport.cs

@@ -556,9 +556,9 @@ public bool IsValidToken(int token)
 
     internal sealed class MetadataException : Exception
     {
-        private int m_hr;
+        private readonly int m_hr;
         internal MetadataException(int hr) { m_hr = hr; }
 
-        public override string ToString() => $"MetadataException HResult = {m_hr:x}.";
+        public override string ToString() => $"{nameof(MetadataException)} HResult = {m_hr:x}.";
     }
 }

src/coreclr/System.Private.CoreLib/src/System/Reflection/RtFieldInfo.cs

@@ -13,8 +13,8 @@ internal sealed unsafe class RtFieldInfo : RuntimeFieldInfo, IRuntimeFieldInfo
     {
         #region Private Data Members
         // aggressive caching
-        private IntPtr m_fieldHandle;
-        private FieldAttributes m_fieldAttributes;
+        private readonly IntPtr m_fieldHandle;
+        private readonly FieldAttributes m_fieldAttributes;
         // lazy caching
         private string? m_name;
         private RuntimeType? m_fieldType;

src/coreclr/System.Private.CoreLib/src/System/Reflection/RuntimeAssembly.cs

@@ -37,7 +37,7 @@ internal sealed partial class RuntimeAssembly : Assembly
         private sealed class ManifestResourceStream : UnmanagedMemoryStream
         {
             // ensures the RuntimeAssembly is kept alive for as long as the stream lives
-            private RuntimeAssembly _manifestAssembly;
+            private readonly RuntimeAssembly _manifestAssembly;
 
             internal unsafe ManifestResourceStream(RuntimeAssembly manifestAssembly, byte* pointer, long length, long capacity, FileAccess access) : base(pointer, length, capacity, access)
             {

src/coreclr/System.Private.CoreLib/src/System/Reflection/RuntimeConstructorInfo.CoreCLR.cs

@@ -16,18 +16,18 @@ namespace System.Reflection
     internal sealed partial class RuntimeConstructorInfo : ConstructorInfo, IRuntimeMethodInfo
     {
         #region Private Data Members
-        private volatile RuntimeType m_declaringType;
-        private RuntimeTypeCache m_reflectedTypeCache;
+        private readonly RuntimeType m_declaringType;
+        private readonly RuntimeTypeCache m_reflectedTypeCache;
         private string? m_toString;
         private ParameterInfo[]? m_parameters; // Created lazily when GetParameters() is called.
-#pragma warning disable CA1823, 414, 169
+#pragma warning disable CA1823, 414, 169, IDE0044
         private object? _empty1; // These empties are used to ensure that RuntimeConstructorInfo and RuntimeMethodInfo are have a layout which is sufficiently similar
         private object? _empty2;
         private object? _empty3;
-#pragma warning restore CA1823, 414, 169
-        private IntPtr m_handle;
-        private MethodAttributes m_methodAttributes;
-        private BindingFlags m_bindingFlags;
+#pragma warning restore CA1823, 414, 169, IDE0044
+        private readonly IntPtr m_handle;
+        private readonly MethodAttributes m_methodAttributes;
+        private readonly BindingFlags m_bindingFlags;
         private Signature? m_signature;
         private ConstructorInvoker? m_invoker;
 

src/coreclr/System.Private.CoreLib/src/System/Reflection/RuntimeEventInfo.cs

@@ -11,17 +11,17 @@ namespace System.Reflection
     internal sealed unsafe class RuntimeEventInfo : EventInfo
     {
         #region Private Data Members
-        private int m_token;
-        private EventAttributes m_flags;
+        private readonly int m_token;
+        private readonly EventAttributes m_flags;
         private string? m_name;
-        private void* m_utf8name;
-        private RuntimeTypeCache m_reflectedTypeCache;
-        private RuntimeMethodInfo? m_addMethod;
-        private RuntimeMethodInfo? m_removeMethod;
-        private RuntimeMethodInfo? m_raiseMethod;
-        private MethodInfo[]? m_otherMethod;
-        private RuntimeType m_declaringType;
-        private BindingFlags m_bindingFlags;
+        private readonly void* m_utf8name;
+        private readonly RuntimeTypeCache m_reflectedTypeCache;
+        private readonly RuntimeMethodInfo? m_addMethod;
+        private readonly RuntimeMethodInfo? m_removeMethod;
+        private readonly RuntimeMethodInfo? m_raiseMethod;
+        private readonly MethodInfo[]? m_otherMethod;
+        private readonly RuntimeType m_declaringType;
+        private readonly BindingFlags m_bindingFlags;
         #endregion
 
         #region Constructor

src/coreclr/System.Private.CoreLib/src/System/Reflection/RuntimeFieldInfo.cs

@@ -9,9 +9,9 @@ namespace System.Reflection
     internal abstract class RuntimeFieldInfo : FieldInfo
     {
         #region Private Data Members
-        private BindingFlags m_bindingFlags;
-        protected RuntimeTypeCache m_reflectedTypeCache;
-        protected RuntimeType m_declaringType;
+        private readonly BindingFlags m_bindingFlags;
+        protected readonly RuntimeTypeCache m_reflectedTypeCache;
+        protected readonly RuntimeType m_declaringType;
         #endregion
 
         #region Constructor

src/coreclr/System.Private.CoreLib/src/System/Reflection/RuntimeMethodInfo.CoreCLR.cs

@@ -16,17 +16,17 @@ namespace System.Reflection
     internal sealed partial class RuntimeMethodInfo : MethodInfo, IRuntimeMethodInfo
     {
         #region Private Data Members
-        private IntPtr m_handle;
-        private RuntimeTypeCache m_reflectedTypeCache;
+        private readonly IntPtr m_handle;
+        private readonly RuntimeTypeCache m_reflectedTypeCache;
         private string? m_name;
         private string? m_toString;
         private ParameterInfo[]? m_parameters;
         private ParameterInfo? m_returnParameter;
-        private BindingFlags m_bindingFlags;
-        private MethodAttributes m_methodAttributes;
+        private readonly BindingFlags m_bindingFlags;
+        private readonly MethodAttributes m_methodAttributes;
         private Signature? m_signature;
-        private RuntimeType m_declaringType;
-        private object? m_keepalive;
+        private readonly RuntimeType m_declaringType;
+        private readonly object? m_keepalive;
         private MethodInvoker? m_invoker;
 
         internal InvocationFlags InvocationFlags

src/coreclr/System.Private.CoreLib/src/System/Reflection/RuntimeModule.cs

@@ -337,11 +337,11 @@ public override void GetPEKind(out PortableExecutableKinds peKind, out ImageFile
 #pragma warning disable CA1823, 169
         // If you add any data members, you need to update the native declaration ReflectModuleBaseObject.
         private RuntimeType m_runtimeType;
-        private RuntimeAssembly m_runtimeAssembly;
-        private IntPtr m_pRefClass;
-        private IntPtr m_pData;
-        private IntPtr m_pGlobals;
-        private IntPtr m_pFields;
+        private readonly RuntimeAssembly m_runtimeAssembly;
+        private readonly IntPtr m_pRefClass;
+        private readonly IntPtr m_pData;
+        private readonly IntPtr m_pGlobals;
+        private readonly IntPtr m_pFields;
 #pragma warning restore CA1823, 169
         #endregion
 

src/coreclr/System.Private.CoreLib/src/System/Reflection/RuntimeParameterInfo.cs

@@ -107,13 +107,13 @@ private static ParameterInfo[] GetParameters(
         #endregion
 
         #region Private Data Members
-        private int m_tkParamDef;
-        private MetadataImport m_scope;
-        private Signature? m_signature;
+        private readonly int m_tkParamDef;
+        private readonly MetadataImport m_scope;
+        private readonly Signature? m_signature;
         private volatile bool m_nameIsCached;
         private readonly bool m_noMetadata;
         private bool m_noDefaultValue;
-        private MethodBase? m_originalMember;
+        private readonly MethodBase? m_originalMember;
         #endregion
 
         #region Internal Properties

src/coreclr/System.Private.CoreLib/src/System/Reflection/RuntimePropertyInfo.cs

@@ -13,16 +13,16 @@ namespace System.Reflection
     internal sealed unsafe class RuntimePropertyInfo : PropertyInfo
     {
         #region Private Data Members
-        private int m_token;
+        private readonly int m_token;
         private string? m_name;
-        private void* m_utf8name;
-        private PropertyAttributes m_flags;
-        private RuntimeTypeCache m_reflectedTypeCache;
-        private RuntimeMethodInfo? m_getterMethod;
-        private RuntimeMethodInfo? m_setterMethod;
-        private MethodInfo[]? m_otherMethod;
-        private RuntimeType m_declaringType;
-        private BindingFlags m_bindingFlags;
+        private readonly void* m_utf8name;
+        private readonly PropertyAttributes m_flags;
+        private readonly RuntimeTypeCache m_reflectedTypeCache;
+        private readonly RuntimeMethodInfo? m_getterMethod;
+        private readonly RuntimeMethodInfo? m_setterMethod;
+        private readonly MethodInfo[]? m_otherMethod;
+        private readonly RuntimeType m_declaringType;
+        private readonly BindingFlags m_bindingFlags;
         private Signature? m_signature;
         private ParameterInfo[]? m_parameters;
         #endregion

src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/RuntimeHelpers.CoreCLR.cs

@@ -381,7 +381,7 @@ private static unsafe void DispatchTailCalls(
             }
         }
 
-#pragma warning disable 0414
+#pragma warning disable 0414, IDE0044
         // Type that represents a managed view of the unmanaged GCFrame
         // data structure in coreclr. The type layouts between the two should match.
         internal unsafe ref struct GCFrameRegistration
@@ -401,7 +401,7 @@ public GCFrameRegistration(void* allocation, uint elemCount, bool areByRefs = tr
                 m_MaybeInterior = areByRefs ? 1 : 0;
             }
         }
-#pragma warning restore 0414
+#pragma warning restore 0414, IDE0044
 
         [MethodImpl(MethodImplOptions.InternalCall)]
         internal static extern unsafe void RegisterForGCReporting(GCFrameRegistration* pRegistration);