[TCGC] Extend isExactName to clients, methods, and enum values

.chronus/changes/tcgc-extend-isexactname-2026-5-21-7-57-0.md

@@ -0,0 +1,7 @@
+---
+changeKind: feature
+packages:
+  - "@azure-tools/typespec-client-generator-core"
+---
+
+Extend `isExactName` to additional SDK types whose names can be changed by `@clientName`: `SdkClientType`, `SdkServiceMethodBase` (and its derived method kinds), and `SdkEnumValueType`. Also fixed `SdkClientType.name` to strip the internal `exact()` marker.

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

@@ -33,7 +33,7 @@ import {
 } from "./internal-utils.js";
 import { createDiagnostic } from "./lib.js";
 import { createSdkMethods, getSdkMethodParameter } from "./methods.js";
-import { getCrossLanguageDefinitionId } from "./public-utils.js";
+import { getCrossLanguageDefinitionId, getLibraryName, isExactClientName } from "./public-utils.js";
 import { getSdkBuiltInType, getSdkCredentialParameter, getTypeSpecBuiltInType } from "./types.js";
 
 function getEndpointTypeFromSingleServer<
@@ -190,17 +190,15 @@ export function createSdkClientType<TServiceOperation extends SdkServiceOperatio
 ): [SdkClientType<TServiceOperation>, readonly Diagnostic[]] {
   const diagnostics = createDiagnosticCollector();
   let name = client.name;
-  if (client.type) {
-    const override = getClientNameOverride(context, client.type);
-    if (override) {
-      name = override;
-    }
+  if (client.type && getClientNameOverride(context, client.type)) {
+    name = getLibraryName(context, client.type);
   }
   const clientType = getActualClientType(client);
   const sdkClientType: SdkClientType<TServiceOperation> = {
     __raw: client,
     kind: "client",
     name,
+    isExactName: client.type ? isExactClientName(context, client.type) : false,
     doc: client.type ? getClientDoc(context, client.type) : undefined,
     summary: client.type ? getSummary(context.program, client.type) : undefined,
     methods: [],

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

@@ -208,6 +208,8 @@ export interface SdkClientType<
   kind: "client";
   /** Name of the client. */
   name: string;
+  /** Whether name should be used exactly as-is, without casing transformations. */
+  isExactName: boolean;
   /** Full qualified namespace. */
   namespace: string;
   /** Document for the type. */
@@ -480,6 +482,8 @@ export interface SdkEnumValueType<
 > extends SdkTypeBase {
   kind: "enumvalue";
   name: string;
+  /** Whether name should be used exactly as-is, without casing transformations. */
+  isExactName: boolean;
   value: string | number;
   enumType: SdkEnumType;
   valueType: TValueType;
@@ -1000,6 +1004,8 @@ interface SdkServiceMethodBase<
 > extends DecoratedType {
   __raw?: Operation;
   name: string;
+  /** Whether name should be used exactly as-is, without casing transformations. */
+  isExactName: boolean;
   /** Whether the type has public or private accessibility */
   access: AccessFlags;
   /** API versions supported for current type. */

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

@@ -80,6 +80,7 @@ import {
   getCrossLanguageDefinitionId,
   getHttpOperationWithCache,
   getLibraryName,
+  isExactClientName,
 } from "./public-utils.js";
 import {
   getClientTypeWithDiagnostics,
@@ -736,6 +737,7 @@ export function getSdkBasicServiceMethod<TServiceOperation extends SdkServiceOpe
     __raw: operation,
     kind: "basic",
     name,
+    isExactName: isExactClientName(context, operation),
     access: getAccess(context, operation) ?? "public",
     parameters: methodParameters,
     doc: getClientDoc(context, operation),

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

@@ -1018,6 +1018,7 @@ function getSdkEnumValueWithDiagnostics(
   return diagnostics.wrap({
     ...diagnostics.pipe(getSdkTypeBaseHelper(context, type, "enumvalue")),
     name: getLibraryName(context, type),
+    isExactName: isExactClientName(context, type),
     value: type.value ?? type.name,
     enumType,
     valueType: enumType.valueType,
@@ -1081,6 +1082,7 @@ function getSdkUnionEnumValues(
     values.push({
       ...diagnostics.pipe(getSdkTypeBaseHelper(context, member.type, "enumvalue")),
       name: name ? name : `${member.value}`,
+      isExactName: isExactClientName(context, member.type),
       value: member.value,
       valueType: enumType.valueType,
       enumType,

packages/typespec-client-generator-core/test/functions/exact.test.ts

@@ -213,6 +213,65 @@ describe("exact", () => {
       const client = sdkPackage.clients[0];
       const method = client.methods[0];
       strictEqual(method.name, "my_exact_op");
+      strictEqual(method.isExactName, true);
+    });
+  });
+
+  describe("exact naming on enum values", () => {
+    it("marks enum value name as exact via exact()", async () => {
+      const { program } = await SimpleBaseTester.compile(
+        createClientCustomizationInput(
+          `
+          @service
+          namespace MyService;
+
+          enum Status {
+            Active,
+            Inactive,
+          }
+
+          op get(@query status: Status): void;
+          `,
+          `
+          #suppress "experimental-feature" "testing exact"
+          @@clientName(MyService.Status.Active, exact("my_active_value"));
+          `,
+        ),
+      );
+
+      const context = await createSdkContextForTester(program);
+      const sdkPackage = context.sdkPackage;
+      const enumType = sdkPackage.enums[0];
+      const activeValue = enumType.values.find((v) => v.name === "my_active_value");
+      strictEqual(activeValue?.isExactName, true);
+      const inactiveValue = enumType.values.find((v) => v.name === "Inactive");
+      strictEqual(inactiveValue?.isExactName, false);
+    });
+  });
+
+  describe("exact naming on clients", () => {
+    it("marks client name as exact via exact()", async () => {
+      const { program } = await SimpleBaseTester.compile(
+        createClientCustomizationInput(
+          `
+          @service
+          namespace MyService;
+
+          @route("/test")
+          op testOp(): void;
+          `,
+          `
+          #suppress "experimental-feature" "testing exact"
+          @@clientName(MyService, exact("my_exact_client"));
+          `,
+        ),
+      );
+
+      const context = await createSdkContextForTester(program);
+      const sdkPackage = context.sdkPackage;
+      const client = sdkPackage.clients[0];
+      strictEqual(client.name, "my_exact_client");
+      strictEqual(client.isExactName, true);
     });
   });
 });