Fix fields named 'read'

crates/bindings-csharp/BSATN.Codegen/Type.cs

@@ -1,5 +1,14 @@
 namespace SpacetimeDB.Codegen;
 
+// Generate code to implement serialization to the BSATN format (https://spacetimedb.com/docs/bsatn).
+// C# doesn't support static methods in interfaces, so instead we declare a zero-sized `struct` type that implements
+// the serialization interface (IReadWrite) for us.
+//
+// See BSATN.Runtime for the support code referenced by code generation,
+// and see Codegen.Tests/fixtures/*/snapshots for examples of generated code.
+// Also, if you set <EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles> in a csproj,
+// you can find the generated code in obj/Debug/*/generated/SpacetimeDB.BSATN.Codegen.
+
 using System.Collections.Immutable;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.CSharp;
@@ -27,6 +36,14 @@ namespace SpacetimeDB.Codegen;
 /// <param name="BSATNName">The name of the BSATN struct for the type.</param>
 public abstract record TypeUse(string Name, string BSATNName)
 {
+    internal static string BSATN_FIELD_SUFFIX = "RW";
+
+    /// <summary>
+    /// The name of the static field containing an IReadWrite in the IReadWrite struct associated with this type.
+    /// We make sure this is different from the field name so that collisions cannot occur.
+    /// </summary>
+    public static string BsatnFieldSuffix => $"{BSATN_FIELD_SUFFIX}";
+
     /// <summary>
     /// Parse a type use for a member.
     /// </summary>
@@ -330,14 +347,20 @@ IEnumerable<MemberDeclaration> members
         var visStr = SyntaxFacts.GetText(visibility);
         return string.Join(
             "\n        ",
-            members.Select(m => $"{visStr} static readonly {m.Type.BSATNName} {m.Name} = new();")
+            members.Select(m =>
+                $"{visStr} static readonly {m.Type.BSATNName} {m.Name}{TypeUse.BsatnFieldSuffix} = new();"
+            )
         );
     }
 
     public static string GenerateDefs(IEnumerable<MemberDeclaration> members) =>
         string.Join(
             ",\n                ",
-            members.Select(m => $"new(nameof({m.Name}), {m.Name}.GetAlgebraicType(registrar))")
+            // we can't use nameof(m.Type.BsatnFieldName) because the bsatn field name differs from the logical name
+            // assigned in the type.
+            members.Select(m =>
+                $"new(\"{m.Name}\", {m.Name}{TypeUse.BsatnFieldSuffix}.GetAlgebraicType(registrar))"
+            )
         );
 }
 
@@ -450,8 +473,6 @@ public Scope.Extensions ToExtensions()
         var extensions = new Scope.Extensions(Scope, FullName);
 
         var bsatnDecls = Members.Cast<MemberDeclaration>();
-        var fieldNames = bsatnDecls.Select(m => m.Name);
-        var fieldNamesAndIds = fieldNames.Select((name, i) => (name, i));
 
         extensions.BaseTypes.Add($"System.IEquatable<{ShortName}>");
 
@@ -480,8 +501,8 @@ public override string ToString() =>
                     return reader.ReadByte() switch {
                         {{string.Join(
                             "\n            ",
-                            fieldNames.Select((name, i) =>
-                                $"{i} => new {name}({name}.Read(reader)),"
+                            bsatnDecls.Select((m, i) =>
+                                $"{i} => new {m.Name}({m.Name}{TypeUse.BsatnFieldSuffix}.Read(reader)),"
                             )
                         )}}
                         _ => throw new System.InvalidOperationException("Invalid tag value, this state should be unreachable.")
@@ -492,12 +513,12 @@ public override string ToString() =>
             switch (value) {
             {{string.Join(
                 "\n",
-                fieldNames.Select((name, i) => $"""
-                            case {name}(var inner):
-                                writer.Write((byte){i});
-                                {name}.Write(writer, inner);
-                                break;
-                """))}}
+                bsatnDecls.Select((m, i) => $"""
+                                                            case {m.Name}(var inner):
+                                                                writer.Write((byte){i});
+                                                                {m.Name}{TypeUse.BsatnFieldSuffix}.Write(writer, inner);
+                                                                break;
+                                                """))}}
                         }
             """;
 
@@ -530,14 +551,14 @@ public override string ToString() =>
                 public void ReadFields(System.IO.BinaryReader reader) {
             {{string.Join(
                     "\n",
-                    fieldNames.Select(name => $"        {name} = BSATN.{name}.Read(reader);")
+                    bsatnDecls.Select(m => $"        {m.Name} = BSATN.{m.Name}{TypeUse.BsatnFieldSuffix}.Read(reader);")
                 )}}
                 }
 
                 public void WriteFields(System.IO.BinaryWriter writer) {
             {{string.Join(
                     "\n",
-                    fieldNames.Select(name => $"        BSATN.{name}.Write(writer, {name});")
+                    bsatnDecls.Select(m => $"        BSATN.{m.Name}{TypeUse.BsatnFieldSuffix}.Write(writer, {m.Name});")
                 )}}
                 }
 
@@ -557,7 +578,7 @@ object SpacetimeDB.BSATN.IStructuralReadWrite.GetSerializer() {
                 public override string ToString() =>
                     $"{{ShortName}} {{start}} {{string.Join(
                         ", ",
-                        fieldNames.Select(name => $$"""{{name}} = {SpacetimeDB.BSATN.StringUtil.GenericToString({{name}})}""")
+                        bsatnDecls.Select(m => $$"""{{m.Name}} = {SpacetimeDB.BSATN.StringUtil.GenericToString({{m.Name}})}""")
                     )}} {{end}}";
             """
             );

crates/bindings-csharp/Codegen.Tests/fixtures/client/snapshots/Type#CustomClass.verified.cs

@@ -6,14 +6,14 @@ partial struct CustomClass : System.IEquatable<CustomClass>, SpacetimeDB.BSATN.I
 {
     public void ReadFields(System.IO.BinaryReader reader)
     {
-        IntField = BSATN.IntField.Read(reader);
-        StringField = BSATN.StringField.Read(reader);
+        IntField = BSATN.IntFieldRW.Read(reader);
+        StringField = BSATN.StringFieldRW.Read(reader);
     }
 
     public void WriteFields(System.IO.BinaryWriter writer)
     {
-        BSATN.IntField.Write(writer, IntField);
-        BSATN.StringField.Write(writer, StringField);
+        BSATN.IntFieldRW.Write(writer, IntField);
+        BSATN.StringFieldRW.Write(writer, StringField);
     }
 
     object SpacetimeDB.BSATN.IStructuralReadWrite.GetSerializer()
@@ -26,8 +26,8 @@ public override string ToString() =>
 
     public readonly partial struct BSATN : SpacetimeDB.BSATN.IReadWrite<CustomClass>
     {
-        internal static readonly SpacetimeDB.BSATN.I32 IntField = new();
-        internal static readonly SpacetimeDB.BSATN.String StringField = new();
+        internal static readonly SpacetimeDB.BSATN.I32 IntFieldRW = new();
+        internal static readonly SpacetimeDB.BSATN.String StringFieldRW = new();
 
         public CustomClass Read(System.IO.BinaryReader reader)
         {
@@ -47,8 +47,8 @@ SpacetimeDB.BSATN.ITypeRegistrar registrar
             registrar.RegisterType<CustomClass>(_ => new SpacetimeDB.BSATN.AlgebraicType.Product(
                 new SpacetimeDB.BSATN.AggregateElement[]
                 {
-                    new(nameof(IntField), IntField.GetAlgebraicType(registrar)),
-                    new(nameof(StringField), StringField.GetAlgebraicType(registrar))
+                    new("IntField", IntFieldRW.GetAlgebraicType(registrar)),
+                    new("StringField", StringFieldRW.GetAlgebraicType(registrar))
                 }
             ));
 

crates/bindings-csharp/Codegen.Tests/fixtures/client/snapshots/Type#CustomStruct.verified.cs

@@ -8,14 +8,14 @@ partial struct CustomStruct
 {
     public void ReadFields(System.IO.BinaryReader reader)
     {
-        IntField = BSATN.IntField.Read(reader);
-        StringField = BSATN.StringField.Read(reader);
+        IntField = BSATN.IntFieldRW.Read(reader);
+        StringField = BSATN.StringFieldRW.Read(reader);
     }
 
     public void WriteFields(System.IO.BinaryWriter writer)
     {
-        BSATN.IntField.Write(writer, IntField);
-        BSATN.StringField.Write(writer, StringField);
+        BSATN.IntFieldRW.Write(writer, IntField);
+        BSATN.StringFieldRW.Write(writer, StringField);
     }
 
     object SpacetimeDB.BSATN.IStructuralReadWrite.GetSerializer()
@@ -28,8 +28,8 @@ public override string ToString() =>
 
     public readonly partial struct BSATN : SpacetimeDB.BSATN.IReadWrite<CustomStruct>
     {
-        internal static readonly SpacetimeDB.BSATN.I32 IntField = new();
-        internal static readonly SpacetimeDB.BSATN.String StringField = new();
+        internal static readonly SpacetimeDB.BSATN.I32 IntFieldRW = new();
+        internal static readonly SpacetimeDB.BSATN.String StringFieldRW = new();
 
         public CustomStruct Read(System.IO.BinaryReader reader)
         {
@@ -49,8 +49,8 @@ SpacetimeDB.BSATN.ITypeRegistrar registrar
             registrar.RegisterType<CustomStruct>(_ => new SpacetimeDB.BSATN.AlgebraicType.Product(
                 new SpacetimeDB.BSATN.AggregateElement[]
                 {
-                    new(nameof(IntField), IntField.GetAlgebraicType(registrar)),
-                    new(nameof(StringField), StringField.GetAlgebraicType(registrar))
+                    new("IntField", IntFieldRW.GetAlgebraicType(registrar)),
+                    new("StringField", StringFieldRW.GetAlgebraicType(registrar))
                 }
             ));
 

crates/bindings-csharp/Codegen.Tests/fixtures/client/snapshots/Type#CustomTaggedEnum.verified.cs

@@ -18,15 +18,15 @@ public override string ToString() =>
 
     public readonly partial struct BSATN : SpacetimeDB.BSATN.IReadWrite<CustomTaggedEnum>
     {
-        internal static readonly SpacetimeDB.BSATN.I32 IntVariant = new();
-        internal static readonly SpacetimeDB.BSATN.String StringVariant = new();
+        internal static readonly SpacetimeDB.BSATN.I32 IntVariantRW = new();
+        internal static readonly SpacetimeDB.BSATN.String StringVariantRW = new();
 
         public CustomTaggedEnum Read(System.IO.BinaryReader reader)
         {
             return reader.ReadByte() switch
             {
-                0 => new IntVariant(IntVariant.Read(reader)),
-                1 => new StringVariant(StringVariant.Read(reader)),
+                0 => new IntVariant(IntVariantRW.Read(reader)),
+                1 => new StringVariant(StringVariantRW.Read(reader)),
                 _
                     => throw new System.InvalidOperationException(
                         "Invalid tag value, this state should be unreachable."
@@ -40,11 +40,11 @@ public void Write(System.IO.BinaryWriter writer, CustomTaggedEnum value)
             {
                 case IntVariant(var inner):
                     writer.Write((byte)0);
-                    IntVariant.Write(writer, inner);
+                    IntVariantRW.Write(writer, inner);
                     break;
                 case StringVariant(var inner):
                     writer.Write((byte)1);
-                    StringVariant.Write(writer, inner);
+                    StringVariantRW.Write(writer, inner);
                     break;
             }
         }
@@ -55,8 +55,8 @@ SpacetimeDB.BSATN.ITypeRegistrar registrar
             registrar.RegisterType<CustomTaggedEnum>(_ => new SpacetimeDB.BSATN.AlgebraicType.Sum(
                 new SpacetimeDB.BSATN.AggregateElement[]
                 {
-                    new(nameof(IntVariant), IntVariant.GetAlgebraicType(registrar)),
-                    new(nameof(StringVariant), StringVariant.GetAlgebraicType(registrar))
+                    new("IntVariant", IntVariantRW.GetAlgebraicType(registrar)),
+                    new("StringVariant", StringVariantRW.GetAlgebraicType(registrar))
                 }
             ));