fixes crahes with some recursive patterns (#281)

Cecilifier.Core.Tests/Tests/Unit/PatternExpressionTests.cs

@@ -119,11 +119,36 @@ private static IEnumerable RecursivePatternsTestScenarios()
  { TestName = "Multiple Properties" };
 
  // Issue #281
- // yield return new TestCaseData(
- // "void M(object o) { var r = o is System.Uri { Host.Length: 10 }; }",
- // "TODO: //DEFINE EXPECTATION")
- // {
- // TestName = "Property (MemberAccessExpression)"
- // };
+ yield return new TestCaseData(
+ "void M(object o) { var r = o is System.Uri { Host.Length: 10 }; }",
+ """
+ //var r = o is System.Uri { Host.Length: 10 };
+ \s+var l_r_\d+ = new VariableDefinition\(assembly.MainModule.TypeSystem.Boolean\);
+ \s+m_M_\d+.Body.Variables.Add\(l_r_\d+\);
+ \s+il_M_\d+.Emit\(OpCodes.Ldarg_1\);
+ \s+var l_tmp_\d+ = new VariableDefinition\(assembly.MainModule.ImportReference\(typeof\(System.Uri\)\)\);
+ \s+m_M_\d+.Body.Variables.Add\(l_tmp_\d+\);
+ \s+var ldc_I4_0_\d+ = il_M_\d+.Create\(OpCodes.Ldc_I4_0\);
+ \s+var nop_\d+ = il_M_\d+.Create\(OpCodes.Nop\);
+ (\s+il_M_\d+\.Emit\(OpCodes\.)Isinst, assembly.MainModule.ImportReference\(typeof\(System.Uri\)\)\);
+ \1Stloc, l_tmp_\d+\);
+ \1Ldloc, l_tmp_\d+\);
+ \1Brfalse_S, ldc_I4_0_\d+\);
+ \1Ldloc, l_tmp_\d+\);
+ \1Callvirt, .+ImportReference\(.+ResolveMethod\(typeof\(System.Uri\), "get_Host",.+\)\)\);
+ \1Callvirt, .+ImportReference\(.+ResolveMethod\(typeof\(System.String\), "get_Length",.+\)\)\);
+ \1Ldc_I4, 10\);
+ \1Bne_Un, ldc_I4_0_\d+\);
+ \1Ldc_I4_1\);
+ \1Br_S, nop_\d+\);
+ \s+il_M_\d+.Append\(ldc_I4_0_\d+\);
+ \s+il_M_\d+.Append\(nop_\d+\);
+ \1Stloc, l_r_\d+\);
+ \1Ret\);
+ \s+//End of local function.
+ """)
+ {
+ TestName = "Property (MemberAccessExpression)"
+ };
  }
 }

Cecilifier.Core/AST/ExpressionVisitor.cs

@@ -871,7 +871,7 @@ public override void VisitRecursivePattern(RecursivePatternSyntax node)
  Context.EmitCilInstruction(ilVar, OpCodes.Ldloc, localVar);
  pattern.Accept(this);
 
- var comparisonType = Context.SemanticModel.GetSymbolInfo(pattern.NameColon.Name).Symbol.GetMemberType();
+ var comparisonType = Context.SemanticModel.GetSymbolInfo(pattern.NameColon?.Name ?? pattern.ExpressionColon?.Expression).Symbol.GetMemberType();
  var opEquality = comparisonType.GetMembers().FirstOrDefault(m => m.Kind == SymbolKind.Method && m.Name == "op_Equality");
  if (opEquality != null)
  {
@@ -1231,7 +1231,7 @@ private void ProcessProperty(SimpleNameSyntax node, IPropertySymbol propertySymb
  {
  propertySymbol.EnsurePropertyExists(Context, node);
 
- if (!propertySymbol.IsStatic && !node.IsQualifiedAccessToTypeOrMember())
+ if (!propertySymbol.IsStatic && node.IsMemberAccessThroughImplicitThis())
  {
  // if this is an *unqualified* access we need to load *this*
  Context.EmitCilInstruction(ilVar, OpCodes.Ldarg_0);

Cecilifier.Core/AST/SyntaxWalkerBase.cs

@@ -466,7 +466,7 @@ protected void ProcessField(string ilVar, SimpleNameSyntax node, IFieldSymbol fi
 
  var fieldDeclarationVariable = fieldSymbol.EnsureFieldExists(Context, node);
 
- if (!fieldSymbol.IsStatic && !node.IsQualifiedAccessToTypeOrMember())
+ if (!fieldSymbol.IsStatic && node.IsMemberAccessThroughImplicitThis())
  Context.EmitCilInstruction(ilVar, OpCodes.Ldarg_0);
 
  if (HandleLoadAddressOnStorage(ilVar, fieldSymbol.Type, node, fieldSymbol.IsStatic ? OpCodes.Ldsflda : OpCodes.Ldflda, fieldSymbol.Name, VariableMemberKind.Field, fieldSymbol.ContainingType.ToDisplayString()))

Cecilifier.Core/Extensions/SyntaxNodeExtensions.cs

@@ -23,12 +23,13 @@ public static class SyntaxNodeExtensions
  /// 1. in, `Foo f = new NS.Foo();`, `Foo` : Foo f => Unqualified, NS.Foo => Qualified
  /// 2. `o.field ?? otherField`, otherField => Unqualified, `field` in `o.field` => Qualified
  /// </remarks>
- public static bool IsQualifiedAccessToTypeOrMember(this SimpleNameSyntax node) => node.Parent switch
+ public static bool IsMemberAccessThroughImplicitThis(this SyntaxNode node) => node.Parent switch
  {
- MemberAccessExpressionSyntax mae => mae.Name == node,
- MemberBindingExpressionSyntax mbe => mbe.Name == node, // A MemberBindExpression represents `?.` in the null conditional operator, for instance, `o?.member`
- NameColonSyntax => true, // A NameColon syntax represents the `Length: 42` in an expression like `o as string { Length: 42 }`. In this case, `Length` is equivalent to `o.Length`
- _ => false
+ MemberAccessExpressionSyntax mae => mae.Name != node && mae.IsMemberAccessThroughImplicitThis(),
+ MemberBindingExpressionSyntax mbe => mbe.Name != node, // A MemberBindExpression represents `?.` in the null conditional operator, for instance, `o?.member`
+ NameColonSyntax => false, // A NameColon syntax represents the `Length: 42` in an expression like `o as string { Length: 42 }`. In this case, `Length` is equivalent to `o.Length`
+ ExpressionColonSyntax => false, // `o as Uri { Host.Length : 10 }`. Parent of `Host.Length` (which is equivalent to `o.Host.Length`) is an ExpressionColonSyntax
+ _ => true
  };
 
  /// <summary>