refactor(http-client-csharp): do not flatten property in emitter (#4449)

Per discussion, we thought we should not flatten properties in emitter,
to keep it as simple as possible.
The flattening logic should be implemented in generator.

part of Azure/autorest.csharp#4788

---------

Co-authored-by: Mingzhe Huang (from Dev Box) <mingzhehuang@microsoft.com>

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

@@ -133,24 +133,20 @@ export function fromSdkModelType(
       ? fromSdkType(modelType.additionalProperties, context, typeMap)
       : undefined;
 
-    const propertiesDict = new Map<SdkModelPropertyType, InputModelProperty[]>();
+    const propertiesDict = new Map<SdkModelPropertyType, InputModelProperty>();
     for (const property of modelType.properties) {
       if (property.kind !== "property") {
         continue;
       }
-      const ourProperties = fromSdkModelProperty(
-        property,
-        {
-          ModelName: modelTypeName,
-          Usage: modelType.usage,
-        } as LiteralTypeContext,
-        [],
-      );
-      propertiesDict.set(property, ourProperties);
+      const ourProperty = fromSdkModelProperty(property, {
+        ModelName: modelTypeName,
+        Usage: modelType.usage,
+      } as LiteralTypeContext);
+      propertiesDict.set(property, ourProperty);
     }
 
     inputModelType.discriminatorProperty = modelType.discriminatorProperty
-      ? propertiesDict.get(modelType.discriminatorProperty)![0]
+      ? propertiesDict.get(modelType.discriminatorProperty)
       : undefined;
 
     inputModelType.baseModel = modelType.baseModel
@@ -174,56 +170,37 @@ export function fromSdkModelType(
   function fromSdkModelProperty(
     property: SdkBodyModelPropertyType,
     literalTypeContext: LiteralTypeContext,
-    flattenedNamePrefixes: string[],
-  ): InputModelProperty[] {
-    // TODO -- we should consolidate the flatten somewhere else
-    if (!property.flatten) {
-      /* remove this when https://github.com/Azure/typespec-azure/issues/1483 and https://github.com/Azure/typespec-azure/issues/1488 are resolved. */
-      let targetType = property.type;
-      if (targetType.kind === "model") {
-        const body = targetType.properties.find((x) => x.kind === "body");
-        if (body) targetType = body.type;
-      }
-
-      const serializedName = property.serializedName;
-      literalTypeContext.PropertyName = serializedName;
-
-      const modelProperty: InputModelProperty = {
-        kind: property.kind,
-        name: property.name,
-        serializedName: serializedName,
-        description: property.description,
-        type: fromSdkType(
-          targetType,
-          context,
-          typeMap,
-          property.discriminator ? undefined : literalTypeContext, // this is a workaround because the type of discriminator property in derived models is always literal and we wrap literal into enums, which leads to a lot of extra enum types, adding this check to avoid them
-        ),
-        optional: property.optional,
-        readOnly: isReadOnly(property), // TODO -- we might pass the visibility through and then check if there is only read to know if this is readonly
-        discriminator: property.discriminator,
-        flattenedNames:
-          flattenedNamePrefixes.length > 0
-            ? flattenedNamePrefixes.concat(property.name)
-            : undefined,
-        decorators: property.decorators,
-        crossLanguageDefinitionId: property.crossLanguageDefinitionId,
-      };
-
-      return [modelProperty];
+  ): InputModelProperty {
+    /* remove this when https://github.com/Azure/typespec-azure/issues/1483 and https://github.com/Azure/typespec-azure/issues/1488 are resolved. */
+    let targetType = property.type;
+    if (targetType.kind === "model") {
+      const body = targetType.properties.find((x) => x.kind === "body");
+      if (body) targetType = body.type;
     }
 
-    const flattenedProperties: InputModelProperty[] = [];
-    const childPropertiesToFlatten = (property.type as SdkModelType).properties;
-    const newFlattenedNamePrefixes = flattenedNamePrefixes.concat(property.serializedName);
-    for (const childProperty of childPropertiesToFlatten) {
-      if (childProperty.kind !== "property") continue;
-      flattenedProperties.push(
-        ...fromSdkModelProperty(childProperty, literalTypeContext, newFlattenedNamePrefixes),
-      );
-    }
+    const serializedName = property.serializedName;
+    literalTypeContext.PropertyName = serializedName;
+
+    const modelProperty: InputModelProperty = {
+      kind: property.kind,
+      name: property.name,
+      serializedName: serializedName,
+      description: property.description,
+      type: fromSdkType(
+        targetType,
+        context,
+        typeMap,
+        property.discriminator ? undefined : literalTypeContext, // this is a workaround because the type of discriminator property in derived models is always literal and we wrap literal into enums, which leads to a lot of extra enum types, adding this check to avoid them
+      ),
+      optional: property.optional,
+      readOnly: isReadOnly(property), // TODO -- we might pass the visibility through and then check if there is only read to know if this is readonly
+      discriminator: property.discriminator,
+      flatten: property.flatten,
+      decorators: property.decorators,
+      crossLanguageDefinitionId: property.crossLanguageDefinitionId,
+    };
 
-    return flattenedProperties;
+    return modelProperty;
   }
 }
 

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

@@ -106,7 +106,7 @@ export interface InputModelProperty extends InputTypeBase {
   readOnly: boolean;
   discriminator: boolean;
   crossLanguageDefinitionId: string;
-  flattenedNames?: string[]; // TODO -- remove this when we are ready to move the flatten handling from emitter to the generator
+  flatten: boolean;
 }
 
 export function isInputModelType(type: InputType): type is InputModelType {

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

@@ -1,13 +1,14 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
 
+using System;
 using System.Collections.Generic;
 
 namespace Microsoft.Generator.CSharp.Input
 {
     public class InputModelProperty
     {
-        public InputModelProperty(string name, string serializedName, string? description, InputType type, bool isRequired, bool isReadOnly, bool isDiscriminator, IReadOnlyList<string>? flattenedNames = null)
+        public InputModelProperty(string name, string serializedName, string? description, InputType type, bool isRequired, bool isReadOnly, bool isDiscriminator)
         {
             Name = name;
             SerializedName = serializedName;
@@ -16,7 +17,6 @@ public InputModelProperty(string name, string serializedName, string? descriptio
             IsRequired = isRequired;
             IsReadOnly = isReadOnly;
             IsDiscriminator = isDiscriminator;
-            FlattenedNames = flattenedNames ?? [];
         }
 
         public string Name { get; }
@@ -27,7 +27,6 @@ public InputModelProperty(string name, string serializedName, string? descriptio
         public bool IsReadOnly { get; }
         public bool IsDiscriminator { get; }
         public InputModelType? EnclosingType { get; internal set; }
-        public IReadOnlyList<string> FlattenedNames { get; }
         public IReadOnlyList<InputDecoratorInfo> Decorators { get; internal set; } = new List<InputDecoratorInfo>();
     }
 }

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

@@ -103,8 +103,7 @@ internal set
                             DiscriminatorProperty.Type,
                             DiscriminatorProperty.IsRequired,
                             DiscriminatorProperty.IsReadOnly,
-                            DiscriminatorProperty.IsDiscriminator,
-                            DiscriminatorProperty.FlattenedNames),
+                            DiscriminatorProperty.IsDiscriminator),
                         new Dictionary<string, InputModelType>(),
                         null,
                         false)

packages/http-client-csharp/generator/Microsoft.Generator.CSharp.Input/src/InputTypes/Serialization/TypeSpecInputModelPropertyConverter.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;
@@ -33,7 +33,6 @@ private static InputModelProperty ReadInputModelProperty(ref Utf8JsonReader read
             bool isOptional = false;
             bool isDiscriminator = false;
             IReadOnlyList<InputDecoratorInfo>? decorators = null;
-            IReadOnlyList<string>? flattenedNames = null;
 
             while (reader.TokenType != JsonTokenType.EndObject)
             {
@@ -45,8 +44,7 @@ private static InputModelProperty ReadInputModelProperty(ref Utf8JsonReader read
                     || reader.TryReadBoolean("readOnly", ref isReadOnly)
                     || reader.TryReadBoolean("optional", ref isOptional)
                     || reader.TryReadBoolean("discriminator", ref isDiscriminator)
-                    || reader.TryReadWithConverter("decorators", options, ref decorators)
-                    || reader.TryReadWithConverter("flattenNames", options, ref flattenedNames);
+                    || reader.TryReadWithConverter("decorators", options, ref decorators);
 
                 if (!isKnownProperty)
                 {
@@ -59,7 +57,7 @@ private static InputModelProperty ReadInputModelProperty(ref Utf8JsonReader read
             // description = BuilderHelpers.EscapeXmlDocDescription(description);
             propertyType = propertyType ?? throw new JsonException($"{nameof(InputModelProperty)} must have a property type.");
 
-            var property = new InputModelProperty(name, serializedName ?? name, description, propertyType, !isOptional, isReadOnly, isDiscriminator, flattenedNames) { Decorators = decorators ?? [] };
+            var property = new InputModelProperty(name, serializedName ?? name, description, propertyType, !isOptional, isReadOnly, isDiscriminator) { Decorators = decorators ?? [] };
             if (id != null)
             {
                 resolver.AddReference(id, property);

packages/http-client-csharp/generator/Microsoft.Generator.CSharp/test/common/InputFactory.cs

@@ -146,8 +146,7 @@ public static InputModelProperty Property(
                 type,
                 isRequired,
                 isReadOnly,
-                isDiscriminator,
-                null);
+                isDiscriminator);
         }
 
         public static InputModelType Model(

packages/http-client-csharp/generator/TestProjects/CadlRanch/http/authentication/api-key/tspCodeModel.json

@@ -27,6 +27,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Authentication.ApiKey.InvalidAuth.error"
     }

packages/http-client-csharp/generator/TestProjects/CadlRanch/http/authentication/http/custom/tspCodeModel.json

@@ -27,6 +27,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Authentication.Http.Custom.InvalidAuth.error"
     }

packages/http-client-csharp/generator/TestProjects/CadlRanch/http/authentication/oauth2/tspCodeModel.json

@@ -27,6 +27,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Authentication.OAuth2.InvalidAuth.error"
     }

packages/http-client-csharp/generator/TestProjects/CadlRanch/http/client/naming/tspCodeModel.json

@@ -118,6 +118,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Client.Naming.Property.ClientNameModel.defaultName"
     }
@@ -147,6 +148,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Client.Naming.Property.LanguageClientNameModel.defaultName"
     }
@@ -176,6 +178,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Client.Naming.Property.ClientNameAndJsonEncodedNameModel.defaultName"
     }
@@ -205,6 +208,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Client.Naming.Model.ModelWithClientClientName.defaultName"
     }
@@ -234,6 +238,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Client.Naming.Model.ModelWithLanguageClientName.defaultName"
     }

packages/http-client-csharp/generator/TestProjects/CadlRanch/http/encode/bytes/tspCodeModel.json

@@ -28,6 +28,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Encode.Bytes.DefaultBytesProperty.value"
     }
@@ -57,6 +58,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Encode.Bytes.Base64BytesProperty.value"
     }
@@ -86,6 +88,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Encode.Bytes.Base64urlBytesProperty.value"
     }
@@ -130,6 +133,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Encode.Bytes.Base64urlArrayBytesProperty.value"
     }

packages/http-client-csharp/generator/TestProjects/CadlRanch/http/encode/datetime/tspCodeModel.json

@@ -35,6 +35,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Encode.Datetime.DefaultDatetimeProperty.value"
     }
@@ -71,6 +72,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Encode.Datetime.Rfc3339DatetimeProperty.value"
     }
@@ -107,6 +109,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Encode.Datetime.Rfc7231DatetimeProperty.value"
     }
@@ -143,6 +146,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Encode.Datetime.UnixTimestampDatetimeProperty.value"
     }
@@ -201,6 +205,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Encode.Datetime.UnixTimestampArrayDatetimeProperty.value"
     }

packages/http-client-csharp/generator/TestProjects/CadlRanch/http/encode/duration/tspCodeModel.json

@@ -35,6 +35,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Encode.Duration.Property.DefaultDurationProperty.value"
     }
@@ -71,6 +72,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Encode.Duration.Property.ISO8601DurationProperty.value"
     }
@@ -107,6 +109,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Encode.Duration.Property.Int32SecondsDurationProperty.value"
     }
@@ -143,6 +146,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Encode.Duration.Property.FloatSecondsDurationProperty.value"
     }
@@ -179,6 +183,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Encode.Duration.Property.Float64SecondsDurationProperty.value"
     }
@@ -237,6 +242,7 @@
      "optional": false,
      "readOnly": false,
      "discriminator": false,
+     "flatten": false,
      "decorators": [],
      "crossLanguageDefinitionId": "Encode.Duration.Property.FloatSecondsDurationArrayProperty.value"
     }