Fixed NullReferenceException when decompiling a switch over a boolean variable that includes a default case.

ICSharpCode.Decompiler/Ast/AstBuilder.cs

@@ -76,7 +76,7 @@ namespace ICSharpCode.Decompiler.Ast
 
 			TypeDefinition type = member as TypeDefinition;
 			if (type != null) {
-				if (type.DeclaringType != null) {
+				if (type.DeclaringType != null) {
 					if (settings.AnonymousMethods && IsClosureType(type))
 						return true;
 					if (settings.YieldReturn && YieldReturnDecompiler.IsCompilerGeneratorEnumerator(type))
@@ -91,12 +91,12 @@ namespace ICSharpCode.Decompiler.Ast
 			
 			FieldDefinition field = member as FieldDefinition;
 			if (field != null) {
-				if (field.IsCompilerGenerated()) {
+				if (field.IsCompilerGenerated()) {
 					if (settings.AnonymousMethods && IsAnonymousMethodCacheField(field))
-						return true;
+						return true;
 					if (settings.AutomaticProperties && IsAutomaticPropertyBackingField(field))
-						return true;
-					if (settings.SwitchStatementOnString && IsSwitchOnStringCache(field))
+						return true;
+					if (settings.SwitchStatementOnString && IsSwitchOnStringCache(field))
 						return true;
 				}
 				// event-fields are not [CompilerGenerated]
@@ -107,24 +107,24 @@ namespace ICSharpCode.Decompiler.Ast
 			return false;
 		}
 
-		static bool IsSwitchOnStringCache(FieldDefinition field)
-		{
-			return field.Name.StartsWith("<>f__switch", StringComparison.Ordinal);
+		static bool IsSwitchOnStringCache(FieldDefinition field)
+		{
+			return field.Name.StartsWith("<>f__switch", StringComparison.Ordinal);
 		}
 
-		static bool IsAutomaticPropertyBackingField(FieldDefinition field)
-		{
-			return field.HasGeneratedName() && field.Name.EndsWith("BackingField", StringComparison.Ordinal);
+		static bool IsAutomaticPropertyBackingField(FieldDefinition field)
+		{
+			return field.HasGeneratedName() && field.Name.EndsWith("BackingField", StringComparison.Ordinal);
 		}
 
-		static bool IsAnonymousMethodCacheField(FieldDefinition field)
-		{
-			return field.Name.StartsWith("CS$<>", StringComparison.Ordinal) || field.Name.StartsWith("<>f__am", StringComparison.Ordinal);
+		static bool IsAnonymousMethodCacheField(FieldDefinition field)
+		{
+			return field.Name.StartsWith("CS$<>", StringComparison.Ordinal) || field.Name.StartsWith("<>f__am", StringComparison.Ordinal);
 		}
 
-		static bool IsClosureType(TypeDefinition type)
-		{
-			return type.HasGeneratedName() && type.IsCompilerGenerated() && (type.Name.Contains("DisplayClass") || type.Name.Contains("AnonStorey"));
+		static bool IsClosureType(TypeDefinition type)
+		{
+			return type.HasGeneratedName() && type.IsCompilerGenerated() && (type.Name.Contains("DisplayClass") || type.Name.Contains("AnonStorey"));
 		}
 		
 		/// <summary>

ICSharpCode.Decompiler/Ast/AstMethodBodyBuilder.cs

@@ -175,7 +175,13 @@ namespace ICSharpCode.Decompiler.Ast
 				};
 			} else if (node is ILSwitch) {
 				ILSwitch ilSwitch = (ILSwitch)node;
-				if (TypeAnalysis.IsBoolean(ilSwitch.Condition.InferredType) && ilSwitch.CaseBlocks.SelectMany(cb => cb.Values).Any(val => val != 0 && val != 1)) {
+				if (TypeAnalysis.IsBoolean(ilSwitch.Condition.InferredType) && (
+					from cb in ilSwitch.CaseBlocks
+					where cb.Values != null
+					from val in cb.Values
+					select val
+				).Any(val => val != 0 && val != 1))
+				{
 					// If switch cases contain values other then 0 and 1, force the condition to be non-boolean
 					ilSwitch.Condition.ExpectedType = typeSystem.Int32;
 				}

ICSharpCode.Decompiler/Tests/Switch.cs

@@ -74,4 +74,16 @@ public static class Switch
 				return "Default";
 		}
 	}
+	
+	public static string SwitchOverBool(bool b)
+	{
+		switch (b) {
+			case true:
+				return bool.TrueString;
+			case false:
+				return bool.FalseString;
+			default:
+				return null;
+		}
+	}
 }