Disable default and ambient attribute at runtime with a feature switch (dotnet#100416)

LakshanF · matouskozak · commit e01c4a4f6188 · 2024-04-30T10:59:46.000+02:00
* Disable default and ambient attribute at runtime with a feature switch

* throwing at the getter at runtime
diff --git a/src/libraries/System.ComponentModel.TypeConverter/src/Resources/Strings.resx b/src/libraries/System.ComponentModel.TypeConverter/src/Resources/Strings.resx
@@ -106,6 +106,9 @@
   <data name="NullableConverterBadCtorArg" xml:space="preserve">
     <value>The specified type is not a nullable type.</value>
   </data>
+  <data name="RuntimeInstanceNotAllowed" xml:space="preserve">
+    <value>Runtime instantiation of this attribute is not allowed.</value>
+  </data>
   <data name="Text" xml:space="preserve">
     <value>(Text)</value>
   </data>
diff --git a/src/libraries/System.ComponentModel.TypeConverter/src/System/ComponentModel/AmbientValueAttribute.cs b/src/libraries/System.ComponentModel.TypeConverter/src/System/ComponentModel/AmbientValueAttribute.cs
@@ -1,6 +1,8 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.ComponentModel.Design;
+using System.Diagnostics;
 using System.Diagnostics.CodeAnalysis;
 
 namespace System.ComponentModel
@@ -12,6 +14,11 @@ namespace System.ComponentModel
     [AttributeUsage(AttributeTargets.All)]
     public sealed class AmbientValueAttribute : Attribute
     {
+        /// <summary>
+        /// This is the default value.
+        /// </summary>
+        private object? _value;
+
         /// <summary>
         /// Initializes a new instance of the <see cref='System.ComponentModel.AmbientValueAttribute'/> class, converting the
         /// specified value to the specified type, and using the U.S. English culture as the
@@ -22,9 +29,15 @@ public AmbientValueAttribute([DynamicallyAccessedMembers(DynamicallyAccessedMemb
         {
             // The try/catch here is because attributes should never throw exceptions. We would fail to
             // load an otherwise normal class.
+
+            if (!IDesignerHost.IsSupported)
+            {
+                return;
+            }
+
             try
             {
-                Value = TypeDescriptor.GetConverter(type).ConvertFromInvariantString(value);
+                _value = TypeDescriptor.GetConverter(type).ConvertFromInvariantString(value);
             }
             catch
             {
@@ -37,7 +50,7 @@ public AmbientValueAttribute([DynamicallyAccessedMembers(DynamicallyAccessedMemb
         /// </summary>
         public AmbientValueAttribute(char value)
         {
-            Value = value;
+            _value = value;
         }
 
         /// <summary>
@@ -46,7 +59,7 @@ public AmbientValueAttribute(char value)
         /// </summary>
         public AmbientValueAttribute(byte value)
         {
-            Value = value;
+            _value = value;
         }
 
         /// <summary>
@@ -55,7 +68,7 @@ public AmbientValueAttribute(byte value)
         /// </summary>
         public AmbientValueAttribute(short value)
         {
-            Value = value;
+            _value = value;
         }
 
         /// <summary>
@@ -64,7 +77,7 @@ public AmbientValueAttribute(short value)
         /// </summary>
         public AmbientValueAttribute(int value)
         {
-            Value = value;
+            _value = value;
         }
 
         /// <summary>
@@ -73,7 +86,7 @@ public AmbientValueAttribute(int value)
         /// </summary>
         public AmbientValueAttribute(long value)
         {
-            Value = value;
+            _value = value;
         }
 
         /// <summary>
@@ -82,7 +95,7 @@ public AmbientValueAttribute(long value)
         /// </summary>
         public AmbientValueAttribute(float value)
         {
-            Value = value;
+            _value = value;
         }
 
         /// <summary>
@@ -91,7 +104,7 @@ public AmbientValueAttribute(float value)
         /// </summary>
         public AmbientValueAttribute(double value)
         {
-            Value = value;
+            _value = value;
         }
 
         /// <summary>
@@ -100,15 +113,15 @@ public AmbientValueAttribute(double value)
         /// </summary>
         public AmbientValueAttribute(bool value)
         {
-            Value = value;
+            _value = value;
         }
 
         /// <summary>
         /// Initializes a new instance of the <see cref='System.ComponentModel.AmbientValueAttribute'/> class using a <see cref='string'/>.
         /// </summary>
         public AmbientValueAttribute(string? value)
         {
-            Value = value;
+            _value = value;
         }
 
         /// <summary>
@@ -117,13 +130,22 @@ public AmbientValueAttribute(string? value)
         /// </summary>
         public AmbientValueAttribute(object? value)
         {
-            Value = value;
+            _value = value;
         }
 
         /// <summary>
         /// Gets the ambient value of the property this attribute is bound to.
         /// </summary>
-        public object? Value { get; }
+        public object? Value {
+            get
+            {
+                if (!IDesignerHost.IsSupported)
+                {
+                    throw new ArgumentException(SR.RuntimeInstanceNotAllowed);
+                }
+                return _value;
+            }
+        }
 
         public override bool Equals([NotNullWhen(true)] object? obj)
         {
diff --git a/src/libraries/System.Private.CoreLib/src/Resources/Strings.resx b/src/libraries/System.Private.CoreLib/src/Resources/Strings.resx
@@ -3359,6 +3359,9 @@
   <data name="RFLCT_Targ_StatMethReqTarg" xml:space="preserve">
     <value>Non-static method requires a target.</value>
   </data>
+  <data name="RuntimeInstanceNotAllowed" xml:space="preserve">
+    <value>Runtime instantiation of this attribute is not allowed.</value>
+  </data>
   <data name="RuntimeWrappedException" xml:space="preserve">
     <value>An object that does not derive from System.Exception has been wrapped in a RuntimeWrappedException.</value>
   </data>
@@ -4313,4 +4316,4 @@
   <data name="WasmThreads_BlockingWaitNotSupportedOnJSInterop" xml:space="preserve">
     <value>Blocking wait is not supported on the JS interop threads.</value>
   </data>
-</root>
+</root>
diff --git a/src/libraries/System.Private.CoreLib/src/System/ComponentModel/DefaultValueAttribute.cs b/src/libraries/System.Private.CoreLib/src/System/ComponentModel/DefaultValueAttribute.cs
@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Diagnostics;
 using System.Diagnostics.CodeAnalysis;
 using System.Globalization;
 using System.Reflection;
@@ -22,6 +23,9 @@ public class DefaultValueAttribute : Attribute
         // Delegate ad hoc created 'TypeDescriptor.ConvertFromInvariantString' reflection object cache
         private static object? s_convertFromInvariantString;
 
+        [FeatureSwitchDefinition("System.ComponentModel.DefaultValueAttribute.IsSupported")]
+        internal static bool IsSupported => AppContext.TryGetSwitch("System.ComponentModel.DefaultValueAttribute.IsSupported", out bool isSupported) ? isSupported : true;
+
         /// <summary>
         /// Initializes a new instance of the <see cref='DefaultValueAttribute'/>
         /// class, converting the specified value to the specified type, and using the U.S. English
@@ -35,6 +39,12 @@ public DefaultValueAttribute(
             // The null check and try/catch here are because attributes should never throw exceptions.
             // We would fail to load an otherwise normal class.
 
+            if (!IsSupported)
+            {
+                Debug.Assert(!IsSupported, "Runtime instantiation of this attribute is not allowed.");
+                return;
+            }
+
             if (type == null)
             {
                 return;
@@ -229,7 +239,18 @@ public DefaultValueAttribute(ulong value)
         /// <summary>
         /// Gets the default value of the property this attribute is bound to.
         /// </summary>
-        public virtual object? Value => _value;
+        public virtual object? Value
+        {
+            get
+            {
+                if (!IsSupported)
+                {
+                    throw new ArgumentException(SR.RuntimeInstanceNotAllowed);
+                }
+                return _value;
+            }
+        }
+
 
         public override bool Equals([NotNullWhen(true)] object? obj)
         {

Original file line number	Diff line number	Diff line change
`@@ -1,6 +1,8 @@`
`1`	`1`	`// Licensed to the .NET Foundation under one or more agreements.`
`2`	`2`	`// The .NET Foundation licenses this file to you under the MIT license.`
`3`	`3`
	`4`	`+using System.ComponentModel.Design;`
	`5`	`+using System.Diagnostics;`
`4`	`6`	`using System.Diagnostics.CodeAnalysis;`
`5`	`7`
`6`	`8`	`namespace System.ComponentModel`
`@@ -12,6 +14,11 @@ namespace System.ComponentModel`
`12`	`14`	`[AttributeUsage(AttributeTargets.All)]`
`13`	`15`	`public sealed class AmbientValueAttribute : Attribute`
`14`	`16`	`{`
	`17`	`+ /// <summary>`
	`18`	`+ /// This is the default value.`
	`19`	`+ /// </summary>`
	`20`	`+ private object? _value;`
	`21`	`+`
`15`	`22`	`/// <summary>`
`16`	`23`	`/// Initializes a new instance of the <see cref='System.ComponentModel.AmbientValueAttribute'/> class, converting the`
`17`	`24`	`/// specified value to the specified type, and using the U.S. English culture as the`
`@@ -22,9 +29,15 @@ public AmbientValueAttribute([DynamicallyAccessedMembers(DynamicallyAccessedMemb`
`22`	`29`	`{`
`23`	`30`	`// The try/catch here is because attributes should never throw exceptions. We would fail to`
`24`	`31`	`// load an otherwise normal class.`
	`32`	`+`
	`33`	`+ if (!IDesignerHost.IsSupported)`
	`34`	`+ {`
	`35`	`+ return;`
	`36`	`+ }`
	`37`	`+`
`25`	`38`	`try`
`26`	`39`	`{`
`27`		`- Value = TypeDescriptor.GetConverter(type).ConvertFromInvariantString(value);`
	`40`	`+ _value = TypeDescriptor.GetConverter(type).ConvertFromInvariantString(value);`
`28`	`41`	`}`
`29`	`42`	`catch`
`30`	`43`	`{`
`@@ -37,7 +50,7 @@ public AmbientValueAttribute([DynamicallyAccessedMembers(DynamicallyAccessedMemb`
`37`	`50`	`/// </summary>`
`38`	`51`	`public AmbientValueAttribute(char value)`
`39`	`52`	`{`
`40`		`- Value = value;`
	`53`	`+ _value = value;`
`41`	`54`	`}`
`42`	`55`
`43`	`56`	`/// <summary>`
`@@ -46,7 +59,7 @@ public AmbientValueAttribute(char value)`
`46`	`59`	`/// </summary>`
`47`	`60`	`public AmbientValueAttribute(byte value)`
`48`	`61`	`{`
`49`		`- Value = value;`
	`62`	`+ _value = value;`
`50`	`63`	`}`
`51`	`64`
`52`	`65`	`/// <summary>`
`@@ -55,7 +68,7 @@ public AmbientValueAttribute(byte value)`
`55`	`68`	`/// </summary>`
`56`	`69`	`public AmbientValueAttribute(short value)`
`57`	`70`	`{`
`58`		`- Value = value;`
	`71`	`+ _value = value;`
`59`	`72`	`}`
`60`	`73`
`61`	`74`	`/// <summary>`
`@@ -64,7 +77,7 @@ public AmbientValueAttribute(short value)`
`64`	`77`	`/// </summary>`
`65`	`78`	`public AmbientValueAttribute(int value)`
`66`	`79`	`{`
`67`		`- Value = value;`
	`80`	`+ _value = value;`
`68`	`81`	`}`
`69`	`82`
`70`	`83`	`/// <summary>`
`@@ -73,7 +86,7 @@ public AmbientValueAttribute(int value)`
`73`	`86`	`/// </summary>`
`74`	`87`	`public AmbientValueAttribute(long value)`
`75`	`88`	`{`
`76`		`- Value = value;`
	`89`	`+ _value = value;`
`77`	`90`	`}`
`78`	`91`
`79`	`92`	`/// <summary>`
`@@ -82,7 +95,7 @@ public AmbientValueAttribute(long value)`
`82`	`95`	`/// </summary>`
`83`	`96`	`public AmbientValueAttribute(float value)`
`84`	`97`	`{`
`85`		`- Value = value;`
	`98`	`+ _value = value;`
`86`	`99`	`}`
`87`	`100`
`88`	`101`	`/// <summary>`
`@@ -91,7 +104,7 @@ public AmbientValueAttribute(float value)`
`91`	`104`	`/// </summary>`
`92`	`105`	`public AmbientValueAttribute(double value)`
`93`	`106`	`{`
`94`		`- Value = value;`
	`107`	`+ _value = value;`
`95`	`108`	`}`
`96`	`109`
`97`	`110`	`/// <summary>`
`@@ -100,15 +113,15 @@ public AmbientValueAttribute(double value)`
`100`	`113`	`/// </summary>`
`101`	`114`	`public AmbientValueAttribute(bool value)`
`102`	`115`	`{`
`103`		`- Value = value;`
	`116`	`+ _value = value;`
`104`	`117`	`}`
`105`	`118`
`106`	`119`	`/// <summary>`
`107`	`120`	`/// Initializes a new instance of the <see cref='System.ComponentModel.AmbientValueAttribute'/> class using a <see cref='string'/>.`
`108`	`121`	`/// </summary>`
`109`	`122`	`public AmbientValueAttribute(string? value)`
`110`	`123`	`{`
`111`		`- Value = value;`
	`124`	`+ _value = value;`
`112`	`125`	`}`
`113`	`126`
`114`	`127`	`/// <summary>`
`@@ -117,13 +130,22 @@ public AmbientValueAttribute(string? value)`
`117`	`130`	`/// </summary>`
`118`	`131`	`public AmbientValueAttribute(object? value)`
`119`	`132`	`{`
`120`		`- Value = value;`
	`133`	`+ _value = value;`
`121`	`134`	`}`
`122`	`135`
`123`	`136`	`/// <summary>`
`124`	`137`	`/// Gets the ambient value of the property this attribute is bound to.`
`125`	`138`	`/// </summary>`
`126`		`- public object? Value { get; }`
	`139`	`+ public object? Value {`
	`140`	`+ get`
	`141`	`+ {`
	`142`	`+ if (!IDesignerHost.IsSupported)`
	`143`	`+ {`
	`144`	`+ throw new ArgumentException(SR.RuntimeInstanceNotAllowed);`
	`145`	`+ }`
	`146`	`+ return _value;`
	`147`	`+ }`
	`148`	`+ }`
`127`	`149`
`128`	`150`	`public override bool Equals([NotNullWhen(true)] object? obj)`
`129`	`151`	`{`