[tcgc] add UsageFlags.MultipartFormData and deprecate `.isFormDataTyp…

…e` (#502)

.chronus/changes/formdata_usage-2024-2-22-14-50-1.md

@@ -0,0 +1,7 @@
+---
+changeKind: feature
+packages:
+  - "@azure-tools/typespec-client-generator-core"
+---
+
+add UsageFlags.MultipartFormData to represent whether a model is used as form data

packages/typespec-client-generator-core/src/decorators.ts

@@ -524,12 +524,12 @@ export function $convenientAPI(
 
 export function shouldGenerateProtocol(context: TCGCContext, entity: Operation): boolean {
   const value = getScopedDecoratorData(context, protocolAPIKey, entity);
-  return value ?? !!context.generateProtocolMethods;
+  return value ?? Boolean(context.generateProtocolMethods);
 }
 
 export function shouldGenerateConvenient(context: TCGCContext, entity: Operation): boolean {
   const value = getScopedDecoratorData(context, convenientAPIKey, entity);
-  return value ?? !!context.generateConvenienceMethods;
+  return value ?? Boolean(context.generateConvenienceMethods);
 }
 
 const excludeKey = createStateSymbol("exclude");

packages/typespec-client-generator-core/src/interfaces.ts

@@ -271,6 +271,9 @@ export interface SdkModelType extends SdkTypeBase {
   kind: "model";
   properties: SdkModelPropertyType[];
   name: string;
+  /**
+   * @deprecated This property is deprecated. Check the bitwise and value of UsageFlags.MultipartFormData nad the `.usage` property on this model
+   */
   isFormDataType: boolean;
   /**
    * @deprecated This property is deprecated. You should not need to check whether a model is an error model.
@@ -540,5 +543,8 @@ export enum UsageFlags {
   Input = 1 << 1,
   Output = 1 << 2,
   ApiVersionEnum = 1 << 3,
+  // Input will also be set when JsonMergePatch is set
   JsonMergePatch = 1 << 4,
+  // Input will also be set when MultipartFormData is set
+  MultipartFormData = 1 << 5,
 }

packages/typespec-client-generator-core/src/internal-utils.ts

@@ -29,6 +29,7 @@ import {
 } from "./interfaces.js";
 import {
   getCrossLanguageDefinitionId,
+  getEffectivePayloadType,
   getHttpOperationWithCache,
   isApiVersion,
 } from "./public-utils.js";
@@ -288,7 +289,7 @@ export function getAllResponseBodies(responses: Record<number, SdkHttpResponse>)
 export function isNullable(type: Type | SdkServiceOperation): boolean {
   if (type.kind === "Union") {
     if (getNonNullOptions(type).length < type.variants.size) return true;
-    return !!ignoreDiagnostics(getUnionAsEnum(type))?.nullable;
+    return Boolean(ignoreDiagnostics(getUnionAsEnum(type))?.nullable);
   }
   if (type.kind === "http") {
     return getAllResponseBodiesAndNonBodyExists(type.responses).nonBodyExists;
@@ -304,3 +305,24 @@ export function isNullable(type: Type | SdkServiceOperation): boolean {
 export function createGeneratedName(type: Namespace | Operation, suffix: string): string {
   return `${getCrossLanguageDefinitionId(type).split(".").at(-1)}${suffix}`;
 }
+
+function isOperationBodyType(context: TCGCContext, type: Type, operation?: Operation): boolean {
+  if (type.kind !== "Model") return false;
+  if (!isHttpOperation(context, operation)) return false;
+  const httpBody = operation
+    ? getHttpOperationWithCache(context, operation).parameters.body
+    : undefined;
+  return Boolean(
+    httpBody &&
+      httpBody.type.kind === "Model" &&
+      getEffectivePayloadType(context, httpBody.type) === getEffectivePayloadType(context, type)
+  );
+}
+
+export function isMultipartFormData(
+  context: TCGCContext,
+  type: Type,
+  operation?: Operation
+): boolean {
+  return isMultipartOperation(context, operation) && isOperationBodyType(context, type, operation);
+}

packages/typespec-client-generator-core/src/types.ts

@@ -92,7 +92,7 @@ import {
   getSdkTypeBaseHelper,
   intOrFloat,
   isAzureCoreModel,
-  isHttpOperation,
+  isMultipartFormData,
   isMultipartOperation,
   isNullable,
   updateWithApiVersionInformation,
@@ -498,18 +498,6 @@ function addDiscriminatorToModelType(
   return diagnostics.wrap(undefined);
 }
 
-function isOperationBodyType(context: TCGCContext, type: Model, operation?: Operation): boolean {
-  if (!isHttpOperation(context, operation)) return false;
-  const httpBody = operation
-    ? getHttpOperationWithCache(context, operation).parameters.body
-    : undefined;
-  return (
-    !!httpBody &&
-    httpBody.type.kind === "Model" &&
-    getEffectivePayloadType(context, httpBody.type) === type
-  );
-}
-
 export function getSdkModel(
   context: TCGCContext,
   type: Model,
@@ -543,8 +531,7 @@ export function getSdkModelWithDiagnostics(
       usage: UsageFlags.None, // dummy value since we need to update models map before we can set this
       crossLanguageDefinitionId: getCrossLanguageDefinitionId(type),
       apiVersions: getAvailableApiVersions(context, type),
-      isFormDataType:
-        isMultipartOperation(context, operation) && isOperationBodyType(context, type, operation),
+      isFormDataType: isMultipartFormData(context, type, operation),
       isError: isErrorModel(context.program, type),
     };
     updateModelsMap(context, type, sdkType, operation);
@@ -1364,6 +1351,11 @@ function updateTypesFromOperation(
         });
       }
     }
+    if (isMultipartFormData(context, httpBody.type, operation)) {
+      bodies.forEach((body) => {
+        updateUsageOfModel(context, UsageFlags.MultipartFormData, body);
+      });
+    }
   }
   for (const response of httpOperation.responses) {
     for (const innerResponse of response.responses) {
@@ -1468,9 +1460,10 @@ function verifyNoConflictingMultipartModelUsage(
   const diagnostics = createDiagnosticCollector();
   for (const [operation, modelMap] of context.operationModelsMap!) {
     for (const [type, sdkType] of modelMap.entries()) {
+      const isMultipartFormData = (sdkType.usage & UsageFlags.MultipartFormData) > 0;
       if (
         sdkType.kind === "model" &&
-        sdkType.isFormDataType !== isMultipartOperation(context, operation)
+        isMultipartFormData !== isMultipartOperation(context, operation)
       ) {
         // This means we have a model that is used both for formdata input and for regular body input
         diagnostics.add(

packages/typespec-client-generator-core/test/types.test.ts

@@ -2791,7 +2791,9 @@ describe("typespec-client-generator-core: types", () => {
       strictEqual(models.length, 1);
       const model = models[0];
       strictEqual(model.kind, "model");
+      // eslint-disable-next-line deprecation/deprecation
       strictEqual(model.isFormDataType, true);
+      ok((model.usage & UsageFlags.MultipartFormData) > 0);
       strictEqual(model.name, "MultiPartRequest");
       strictEqual(model.properties.length, 2);
       const id = model.properties.find((x) => x.name === "id");
@@ -2841,7 +2843,9 @@ describe("typespec-client-generator-core: types", () => {
       const modelA = models.find((x) => x.name === "A");
       ok(modelA);
       strictEqual(modelA.kind, "model");
+      // eslint-disable-next-line deprecation/deprecation
       strictEqual(modelA.isFormDataType, true);
+      ok((modelA.usage & UsageFlags.MultipartFormData) > 0);
       strictEqual(modelA.properties.length, 1);
       const modelAProp = modelA.properties[0];
       strictEqual(modelAProp.kind, "property");
@@ -2850,7 +2854,9 @@ describe("typespec-client-generator-core: types", () => {
       const modelB = models.find((x) => x.name === "B");
       ok(modelB);
       strictEqual(modelB.kind, "model");
+      // eslint-disable-next-line deprecation/deprecation
       strictEqual(modelB.isFormDataType, false);
+      ok((modelB.usage & UsageFlags.MultipartFormData) === 0);
       strictEqual(modelB.properties.length, 1);
       strictEqual(modelB.properties[0].type.kind, "bytes");
     });
@@ -2935,12 +2941,16 @@ describe("typespec-client-generator-core: types", () => {
 
       const pictureWrapper = models.find((x) => x.name === "PictureWrapper");
       ok(pictureWrapper);
+      // eslint-disable-next-line deprecation/deprecation
       strictEqual(pictureWrapper.isFormDataType, true);
+      ok((pictureWrapper.usage & UsageFlags.MultipartFormData) > 0);
 
       const errorResponse = models.find((x) => x.name === "ErrorResponse");
       ok(errorResponse);
       strictEqual(errorResponse.kind, "model");
+      // eslint-disable-next-line deprecation/deprecation
       strictEqual(errorResponse.isFormDataType, false);
+      ok((errorResponse.usage & UsageFlags.MultipartFormData) === 0);
     });
   });
   describe("SdkTupleType", () => {