Fix decompilation of auto properties with explicit implementation

ICSharpCode.Decompiler.Tests/TestCases/Pretty/PropertiesAndEvents.cs

@@ -56,15 +56,9 @@ namespace ICSharpCode.Decompiler.Tests.TestCases.Pretty
 		{
 			private EventHandler Changed;
 
-			private int backingField;
-
 			int IChange.Property {
-				get {
-					return backingField;
-				}
-				set {
-					backingField = value;
-				}
+				get;
+				set;
 			}
 
 			event EventHandler IChange.Changed {

ICSharpCode.Decompiler.Tests/TestCases/Pretty/PropertiesAndEvents.il

@@ -10,9 +10,9 @@
 }
 .assembly PropertiesAndEvents
 {
+  .custom instance void [mscorlib]System.Runtime.CompilerServices.CompilationRelaxationsAttribute::.ctor(int32) = ( 01 00 08 00 00 00 00 00 ) 
   .custom instance void [mscorlib]System.Runtime.CompilerServices.RuntimeCompatibilityAttribute::.ctor() = ( 01 00 01 00 54 02 16 57 72 61 70 4E 6F 6E 45 78   // ....T..WrapNonEx
                                                                                                              63 65 70 74 69 6F 6E 54 68 72 6F 77 73 01 )       // ceptionThrows.
-  .custom instance void [mscorlib]System.Runtime.CompilerServices.CompilationRelaxationsAttribute::.ctor(int32) = ( 01 00 08 00 00 00 00 00 ) 
   .permissionset reqmin
              = {[mscorlib]System.Security.Permissions.SecurityPermissionAttribute = {property bool 'SkipVerification' = bool(true)}}
   .hash algorithm 0x00008004
@@ -303,35 +303,36 @@
          implements ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/IChange
   {
     .field private class [mscorlib]System.EventHandler Changed
-    .field private int32 backingField
+    .field private int32 '<ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.Property>k__BackingField'
+    .custom instance void [mscorlib]System.Runtime.CompilerServices.CompilerGeneratedAttribute::.ctor() = ( 01 00 00 00 ) 
     .method private hidebysig newslot specialname virtual final 
             instance int32  ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.get_Property() cil managed
     {
+      .custom instance void [mscorlib]System.Runtime.CompilerServices.CompilerGeneratedAttribute::.ctor() = ( 01 00 00 00 ) 
       .override ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/IChange::get_Property
-      // Code size       12 (0xc)
+      // Code size       11 (0xb)
       .maxstack  1
       .locals init (int32 V_0)
-      IL_0000:  nop
-      IL_0001:  ldarg.0
-      IL_0002:  ldfld      int32 ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/Change::backingField
-      IL_0007:  stloc.0
-      IL_0008:  br.s       IL_000a
+      IL_0000:  ldarg.0
+      IL_0001:  ldfld      int32 ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/Change::'<ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.Property>k__BackingField'
+      IL_0006:  stloc.0
+      IL_0007:  br.s       IL_0009
 
-      IL_000a:  ldloc.0
-      IL_000b:  ret
+      IL_0009:  ldloc.0
+      IL_000a:  ret
     } // end of method Change::ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.get_Property
 
     .method private hidebysig newslot specialname virtual final 
             instance void  ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.set_Property(int32 'value') cil managed
     {
+      .custom instance void [mscorlib]System.Runtime.CompilerServices.CompilerGeneratedAttribute::.ctor() = ( 01 00 00 00 ) 
       .override ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/IChange::set_Property
-      // Code size       9 (0x9)
+      // Code size       8 (0x8)
       .maxstack  8
-      IL_0000:  nop
-      IL_0001:  ldarg.0
-      IL_0002:  ldarg.1
-      IL_0003:  stfld      int32 ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/Change::backingField
-      IL_0008:  ret
+      IL_0000:  ldarg.0
+      IL_0001:  ldarg.1
+      IL_0002:  stfld      int32 ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/Change::'<ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.Property>k__BackingField'
+      IL_0007:  ret
     } // end of method Change::ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.set_Property
 
     .method private hidebysig newslot specialname virtual final 

ICSharpCode.Decompiler.Tests/TestCases/Pretty/PropertiesAndEvents.opt.il

@@ -10,9 +10,9 @@
 }
 .assembly PropertiesAndEvents.opt
 {
+  .custom instance void [mscorlib]System.Runtime.CompilerServices.CompilationRelaxationsAttribute::.ctor(int32) = ( 01 00 08 00 00 00 00 00 ) 
   .custom instance void [mscorlib]System.Runtime.CompilerServices.RuntimeCompatibilityAttribute::.ctor() = ( 01 00 01 00 54 02 16 57 72 61 70 4E 6F 6E 45 78   // ....T..WrapNonEx
                                                                                                              63 65 70 74 69 6F 6E 54 68 72 6F 77 73 01 )       // ceptionThrows.
-  .custom instance void [mscorlib]System.Runtime.CompilerServices.CompilationRelaxationsAttribute::.ctor(int32) = ( 01 00 08 00 00 00 00 00 ) 
   .permissionset reqmin
              = {[mscorlib]System.Security.Permissions.SecurityPermissionAttribute = {property bool 'SkipVerification' = bool(true)}}
   .hash algorithm 0x00008004
@@ -287,27 +287,30 @@
          implements ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/IChange
   {
     .field private class [mscorlib]System.EventHandler Changed
-    .field private int32 backingField
+    .field private int32 '<ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.Property>k__BackingField'
+    .custom instance void [mscorlib]System.Runtime.CompilerServices.CompilerGeneratedAttribute::.ctor() = ( 01 00 00 00 ) 
     .method private hidebysig newslot specialname virtual final 
             instance int32  ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.get_Property() cil managed
     {
+      .custom instance void [mscorlib]System.Runtime.CompilerServices.CompilerGeneratedAttribute::.ctor() = ( 01 00 00 00 ) 
       .override ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/IChange::get_Property
       // Code size       7 (0x7)
       .maxstack  8
       IL_0000:  ldarg.0
-      IL_0001:  ldfld      int32 ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/Change::backingField
+      IL_0001:  ldfld      int32 ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/Change::'<ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.Property>k__BackingField'
       IL_0006:  ret
     } // end of method Change::ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.get_Property
 
     .method private hidebysig newslot specialname virtual final 
             instance void  ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.set_Property(int32 'value') cil managed
     {
+      .custom instance void [mscorlib]System.Runtime.CompilerServices.CompilerGeneratedAttribute::.ctor() = ( 01 00 00 00 ) 
       .override ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/IChange::set_Property
       // Code size       8 (0x8)
       .maxstack  8
       IL_0000:  ldarg.0
       IL_0001:  ldarg.1
-      IL_0002:  stfld      int32 ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/Change::backingField
+      IL_0002:  stfld      int32 ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/Change::'<ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.Property>k__BackingField'
       IL_0007:  ret
     } // end of method Change::ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.set_Property
 

ICSharpCode.Decompiler.Tests/TestCases/Pretty/PropertiesAndEvents.opt.roslyn.il

@@ -300,27 +300,30 @@
          implements ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/IChange
   {
     .field private class [mscorlib]System.EventHandler Changed
-    .field private int32 backingField
+    .field private int32 '<ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.Property>k__BackingField'
+    .custom instance void [mscorlib]System.Runtime.CompilerServices.CompilerGeneratedAttribute::.ctor() = ( 01 00 00 00 ) 
     .method private hidebysig newslot specialname virtual final 
             instance int32  ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.get_Property() cil managed
     {
+      .custom instance void [mscorlib]System.Runtime.CompilerServices.CompilerGeneratedAttribute::.ctor() = ( 01 00 00 00 ) 
       .override ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/IChange::get_Property
       // Code size       7 (0x7)
       .maxstack  8
       IL_0000:  ldarg.0
-      IL_0001:  ldfld      int32 ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/Change::backingField
+      IL_0001:  ldfld      int32 ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/Change::'<ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.Property>k__BackingField'
       IL_0006:  ret
     } // end of method Change::ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.get_Property
 
     .method private hidebysig newslot specialname virtual final 
             instance void  ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.set_Property(int32 'value') cil managed
     {
+      .custom instance void [mscorlib]System.Runtime.CompilerServices.CompilerGeneratedAttribute::.ctor() = ( 01 00 00 00 ) 
       .override ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/IChange::set_Property
       // Code size       8 (0x8)
       .maxstack  8
       IL_0000:  ldarg.0
       IL_0001:  ldarg.1
-      IL_0002:  stfld      int32 ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/Change::backingField
+      IL_0002:  stfld      int32 ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/Change::'<ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.Property>k__BackingField'
       IL_0007:  ret
     } // end of method Change::ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.set_Property
 

ICSharpCode.Decompiler.Tests/TestCases/Pretty/PropertiesAndEvents.roslyn.il

@@ -308,35 +308,32 @@
          implements ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/IChange
   {
     .field private class [mscorlib]System.EventHandler Changed
-    .field private int32 backingField
+    .field private int32 '<ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.Property>k__BackingField'
+    .custom instance void [mscorlib]System.Runtime.CompilerServices.CompilerGeneratedAttribute::.ctor() = ( 01 00 00 00 ) 
+    .custom instance void [mscorlib]System.Diagnostics.DebuggerBrowsableAttribute::.ctor(valuetype [mscorlib]System.Diagnostics.DebuggerBrowsableState) = ( 01 00 00 00 00 00 00 00 ) 
     .method private hidebysig newslot specialname virtual final 
             instance int32  ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.get_Property() cil managed
     {
+      .custom instance void [mscorlib]System.Runtime.CompilerServices.CompilerGeneratedAttribute::.ctor() = ( 01 00 00 00 ) 
       .override ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/IChange::get_Property
-      // Code size       12 (0xc)
-      .maxstack  1
-      .locals init (int32 V_0)
-      IL_0000:  nop
-      IL_0001:  ldarg.0
-      IL_0002:  ldfld      int32 ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/Change::backingField
-      IL_0007:  stloc.0
-      IL_0008:  br.s       IL_000a
-
-      IL_000a:  ldloc.0
-      IL_000b:  ret
+      // Code size       7 (0x7)
+      .maxstack  8
+      IL_0000:  ldarg.0
+      IL_0001:  ldfld      int32 ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/Change::'<ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.Property>k__BackingField'
+      IL_0006:  ret
     } // end of method Change::ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.get_Property
 
     .method private hidebysig newslot specialname virtual final 
             instance void  ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.set_Property(int32 'value') cil managed
     {
+      .custom instance void [mscorlib]System.Runtime.CompilerServices.CompilerGeneratedAttribute::.ctor() = ( 01 00 00 00 ) 
       .override ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/IChange::set_Property
-      // Code size       9 (0x9)
+      // Code size       8 (0x8)
       .maxstack  8
-      IL_0000:  nop
-      IL_0001:  ldarg.0
-      IL_0002:  ldarg.1
-      IL_0003:  stfld      int32 ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/Change::backingField
-      IL_0008:  ret
+      IL_0000:  ldarg.0
+      IL_0001:  ldarg.1
+      IL_0002:  stfld      int32 ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents/Change::'<ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.Property>k__BackingField'
+      IL_0007:  ret
     } // end of method Change::ICSharpCode.Decompiler.Tests.TestCases.Pretty.PropertiesAndEvents.IChange.set_Property
 
     .method private hidebysig newslot specialname virtual final 

ICSharpCode.Decompiler/CSharp/Transforms/PatternStatementTransform.cs

@@ -488,8 +488,6 @@ namespace ICSharpCode.Decompiler.CSharp.Transforms
 
 		PropertyDeclaration TransformAutomaticProperties(PropertyDeclaration property)
 		{
-			if (!property.PrivateImplementationType.IsNull)
-				return null;
 			PropertyDefinition cecilProperty = context.TypeSystem.GetCecil(property.GetSymbol() as IProperty) as PropertyDefinition;
 			if (cecilProperty == null || cecilProperty.GetMethod == null)
 				return null;