sync emitter/generator changes from Azure/autorest.csharp#4800 (#3548)

packages/http-client-csharp/emitter/src/lib/converter.ts

@@ -273,20 +273,18 @@ function fromUnionType(
   models: Map<string, InputModelType>,
   enums: Map<string, InputEnumType>
 ): InputUnionType | InputType {
-  const itemTypes: InputType[] = [];
+  const variantTypes: InputType[] = [];
   for (const value of union.values) {
-    const inputType = fromSdkType(value, context, models, enums);
-    itemTypes.push(inputType);
+    const variantType = fromSdkType(value, context, models, enums);
+    variantTypes.push(variantType);
   }
 
-  return itemTypes.length > 1
-    ? {
-        Kind: InputTypeKind.Union,
-        Name: InputTypeKind.Union,
-        UnionItemTypes: itemTypes,
-        IsNullable: false,
-      }
-    : itemTypes[0];
+  return {
+    Kind: "union",
+    Name: union.name,
+    VariantTypes: variantTypes,
+    IsNullable: false,
+  };
 }
 
 function fromSdkConstantType(

packages/http-client-csharp/emitter/src/lib/operation.ts

@@ -132,7 +132,7 @@ export function loadOperation(
     if (isInputLiteralType(contentTypeParameter.Type)) {
       mediaTypes.push(contentTypeParameter.DefaultValue?.Value);
     } else if (isInputUnionType(contentTypeParameter.Type)) {
-      for (const unionItem of contentTypeParameter.Type.UnionItemTypes) {
+      for (const unionItem of contentTypeParameter.Type.VariantTypes) {
         if (isInputLiteralType(unionItem)) {
           mediaTypes.push(unionItem.Value as string);
         } else {

packages/http-client-csharp/emitter/src/type/input-type-kind.ts

@@ -2,7 +2,6 @@
 // Licensed under the MIT License. See License.txt in the project root for license information.
 
 export enum InputTypeKind {
-  Union = "Union",
   Model = "Model",
   Array = "Array",
   Dictionary = "Dictionary",

packages/http-client-csharp/emitter/src/type/input-type.ts

@@ -61,13 +61,13 @@ export interface InputDurationType extends InputTypeBase {
 }
 
 export interface InputUnionType extends InputTypeBase {
-  Kind: InputTypeKind.Union; // TODO -- will change to TCGC value in future refactor
-  Name: InputTypeKind.Union; // union type does not really have a name right now, we just use its kind
-  UnionItemTypes: InputType[];
+  Kind: "union";
+  Name: string;
+  VariantTypes: InputType[];
 }
 
 export function isInputUnionType(type: InputType): type is InputUnionType {
-  return type.Kind === InputTypeKind.Union;
+  return type.Kind === "union";
 }
 
 export interface InputModelType extends InputTypeBase {

packages/http-client-csharp/generator/Microsoft.Generator.CSharp.ClientModel/src/ScmTypeFactory.cs

@@ -21,7 +21,7 @@ internal class ScmTypeFactory : TypeFactory
         public override CSharpType CreateCSharpType(InputType inputType) => inputType switch
         {
             InputLiteralType literalType => CSharpType.FromLiteral(CreateCSharpType(literalType.ValueType), literalType.Value),
-            InputUnionType unionType => CSharpType.FromUnion(unionType.UnionItemTypes.Select(CreateCSharpType).ToArray(), unionType.IsNullable),
+            InputUnionType unionType => CSharpType.FromUnion(unionType.VariantTypes.Select(CreateCSharpType).ToArray(), unionType.IsNullable),
             InputListType { IsEmbeddingsVector: true } listType => new CSharpType(typeof(ReadOnlyMemory<>), listType.IsNullable, CreateCSharpType(listType.ElementType)),
             InputListType listType => new CSharpType(typeof(IList<>), listType.IsNullable, CreateCSharpType(listType.ElementType)),
             InputDictionaryType dictionaryType => new CSharpType(typeof(IDictionary<,>), inputType.IsNullable, typeof(string), CreateCSharpType(dictionaryType.ValueType)),

packages/http-client-csharp/generator/Microsoft.Generator.CSharp.Input/src/InputTypes/ExampleMockValueBuilder.cs

@@ -63,7 +63,7 @@ private static InputParameterExample BuildParameterExample(InputParameter parame
                     // when it is constant, it could have DefaultValue
                     value = InputExampleValue.Value(parameter.Type, parameter.DefaultValue.Value);
                 }
-                else if (parameter.Type is InputUnionType unionType && unionType.UnionItemTypes.First() is InputLiteralType literalType)
+                else if (parameter.Type is InputUnionType unionType && unionType.VariantTypes[0] is InputLiteralType literalType)
                 {
                     // or it could be a union of literal types
                     value = InputExampleValue.Value(parameter.Type, literalType.Value);
@@ -106,7 +106,7 @@ private static InputParameterExample BuildParameterExample(InputParameter parame
             InputPrimitiveType primitiveType => BuildPrimitiveExampleValue(primitiveType, hint),
             InputLiteralType literalType => InputExampleValue.Value(literalType, literalType.Value),
             InputModelType modelType => BuildModelExampleValue(modelType, useAllParameters, visitedModels),
-            InputUnionType unionType => BuildExampleValue(unionType.UnionItemTypes.First(), hint, useAllParameters, visitedModels),
+            InputUnionType unionType => BuildExampleValue(unionType.VariantTypes[0], hint, useAllParameters, visitedModels),
             InputDateTimeType dateTimeType => BuildDateTimeExampleValue(dateTimeType),
             InputDurationType durationType => BuildDurationExampleValue(durationType),
             _ => InputExampleValue.Object(type, new Dictionary<string, InputExampleValue>())

packages/http-client-csharp/generator/Microsoft.Generator.CSharp.Input/src/InputTypes/InputUnionType.cs

@@ -7,11 +7,11 @@ namespace Microsoft.Generator.CSharp.Input
 {
     public class InputUnionType : InputType
     {
-        public InputUnionType(string name, IReadOnlyList<InputType> unionItemTypes, bool isNullable) : base(name, isNullable)
+        public InputUnionType(string name, IReadOnlyList<InputType> variantTypes, bool isNullable) : base(name, isNullable)
         {
-            UnionItemTypes = unionItemTypes;
+            VariantTypes = variantTypes;
         }
 
-        public IReadOnlyList<InputType> UnionItemTypes { get; }
+        public IReadOnlyList<InputType> VariantTypes { get; internal set; }
     }
 }

packages/http-client-csharp/generator/Microsoft.Generator.CSharp.Input/src/InputTypes/Serialization/TypeSpecInputModelTypeConverter.cs

@@ -32,19 +32,8 @@ public static InputModelType CreateModelType(ref Utf8JsonReader reader, string?
 
             id = id ?? throw new JsonException();
 
-            // skip every other property until we have a name
-            while (name == null)
-            {
-                var hasName = reader.TryReadString(nameof(InputModelType.Name), ref name);
-                if (!hasName)
-                {
-                    reader.SkipProperty();
-                }
-            }
-            name = name ?? throw new JsonException("Model must have name");
-
             // create an empty model to resolve circular references
-            var model = new InputModelType(name, null, null, null, null, InputModelTypeUsage.None, null!, null, new List<InputModelType>(), null, null, null, false);
+            var model = new InputModelType(name!, null, null, null, null, InputModelTypeUsage.None, null!, null, new List<InputModelType>(), null, null, null, false);
             resolver.AddReference(id, model);
 
             bool isNullable = false;
@@ -62,7 +51,8 @@ public static InputModelType CreateModelType(ref Utf8JsonReader reader, string?
             // read all possible properties and throw away the unknown properties
             while (reader.TokenType != JsonTokenType.EndObject)
             {
-                var isKnownProperty = reader.TryReadBoolean(nameof(InputModelType.IsNullable), ref isNullable)
+                var isKnownProperty = reader.TryReadString(nameof(InputModelType.Name), ref name)
+                    || reader.TryReadBoolean(nameof(InputModelType.IsNullable), ref isNullable)
                     || reader.TryReadString(nameof(InputModelType.Namespace), ref ns)
                     || reader.TryReadString(nameof(InputModelType.Accessibility), ref accessibility)
                     || reader.TryReadString(nameof(InputModelType.Deprecated), ref deprecated)

packages/http-client-csharp/generator/Microsoft.Generator.CSharp.Input/src/InputTypes/Serialization/TypeSpecInputTypeConverter.cs

@@ -50,7 +50,7 @@ private InputType CreateObject(ref Utf8JsonReader reader, JsonSerializerOptions
         }
 
         private const string LiteralKind = "constant";
-        private const string UnionKind = "Union";
+        private const string UnionKind = "union";
         private const string ModelKind = "Model";
         private const string EnumKind = "enum";
         private const string ArrayKind = "Array";

packages/http-client-csharp/generator/Microsoft.Generator.CSharp.Input/src/InputTypes/Serialization/TypeSpecInputUnionTypeConverter.cs

@@ -1,4 +1,4 @@
-// Copyright (c) Microsoft Corporation. All rights reserved.
+// Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
 
 using System;
@@ -24,59 +24,39 @@ public override void Write(Utf8JsonWriter writer, InputUnionType value, JsonSeri
 
         public static InputUnionType CreateInputUnionType(ref Utf8JsonReader reader, string? id, string? name, JsonSerializerOptions options, ReferenceResolver resolver)
         {
-            var isFirstProperty = id == null;
+            if (id == null)
+            {
+                reader.TryReadReferenceId(ref id);
+            }
+
+            id = id ?? throw new JsonException();
+
+            // create an empty model to resolve circular references
+            var union = new InputUnionType(null!, null!, false);
+            resolver.AddReference(id, union);
+
             bool isNullable = false;
-            var unionItemTypes = new List<InputType>();
+            IReadOnlyList<InputType>? variantTypes = null;
             while (reader.TokenType != JsonTokenType.EndObject)
             {
-                var isKnownProperty = reader.TryReadReferenceId(ref isFirstProperty, ref id)
-                    || reader.TryReadString(nameof(InputUnionType.Name), ref name)
+                var isKnownProperty = reader.TryReadString(nameof(InputUnionType.Name), ref name)
+                    || reader.TryReadWithConverter(nameof(InputUnionType.VariantTypes), options, ref variantTypes)
                     || reader.TryReadBoolean(nameof(InputUnionType.IsNullable), ref isNullable);
 
-                if (isKnownProperty)
-                {
-                    continue;
-                }
-
-                if (reader.GetString() == nameof(InputUnionType.UnionItemTypes))
-                {
-                    reader.Read();
-                    CreateUnionItemTypes(ref reader, unionItemTypes, options);
-                }
-                else
+                if (!isKnownProperty)
                 {
                     reader.SkipProperty();
                 }
             }
 
-            name = name ?? throw new JsonException($"{nameof(InputLiteralType)} must have a name.");
-            if (unionItemTypes == null || unionItemTypes.Count == 0)
+            union.Name = name ?? throw new JsonException($"{nameof(InputLiteralType)} must have a name.");
+            if (variantTypes == null || variantTypes.Count == 0)
             {
                 throw new JsonException("Union must have a least one union type");
             }
-
-            var unionType = new InputUnionType(name, unionItemTypes, isNullable);
-            if (id != null)
-            {
-                resolver.AddReference(id, unionType);
-            }
-            return unionType;
-        }
-
-        private static void CreateUnionItemTypes(ref Utf8JsonReader reader, ICollection<InputType> itemTypes, JsonSerializerOptions options)
-        {
-            if (reader.TokenType != JsonTokenType.StartArray)
-            {
-                throw new JsonException();
-            }
-            reader.Read();
-
-            while (reader.TokenType != JsonTokenType.EndArray)
-            {
-                var type = reader.ReadWithConverter<InputType>(options);
-                itemTypes.Add(type ?? throw new JsonException($"null {nameof(InputType)} isn't allowed"));
-            }
-            reader.Read();
+            union.VariantTypes = variantTypes;
+            union.IsNullable = isNullable;
+            return union;
         }
     }
 }

packages/http-client-csharp/generator/TestProjects/Local/Unbranded-TypeSpec/tspCodeModel.json

@@ -428,9 +428,9 @@
      "Description": "required Union",
      "Type": {
       "$id": "64",
-      "Kind": "Union",
-      "Name": "Union",
-      "UnionItemTypes": [
+      "Kind": "union",
+      "Name": "ThingRequiredUnion",
+      "VariantTypes": [
        {
         "$id": "65",
         "Kind": "string",