prevent carry over for @clientName

.chronus/changes/prevent-carry-over-2024-2-13-14-34-30.md

@@ -0,0 +1,7 @@
+---
+changeKind: fix
+packages:
+  - "@azure-tools/typespec-client-generator-core"
+---
+
+prevent carry over for `@clientName`

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

@@ -1,5 +1,7 @@
 import {
+  AugmentDecoratorStatementNode,
   DecoratorContext,
+  DecoratorExpressionNode,
   DecoratorFunction,
   EmitContext,
   Enum,
@@ -16,6 +18,7 @@ import {
   Union,
   getNamespaceFullName,
   getProjectedName,
+  ignoreDiagnostics,
   isService,
   isTemplateDeclaration,
   isTemplateDeclarationOrInstance,
@@ -818,6 +821,27 @@ export function $clientName(
   value: string,
   scope?: LanguageScopes
 ) {
+  // workaround for current lack of functionality in compiler
+  // https://github.com/microsoft/typespec/issues/2717
+  if (entity.kind === "Model" || entity.kind === "Operation") {
+    if ((context.decoratorTarget as Node).kind === SyntaxKind.AugmentDecoratorStatement) {
+      if (
+        ignoreDiagnostics(
+          context.program.checker.resolveTypeReference(
+            (context.decoratorTarget as AugmentDecoratorStatementNode).targetType
+          )
+        ) !== entity
+      ) {
+        return;
+      }
+    }
+    if ((context.decoratorTarget as Node).kind === SyntaxKind.DecoratorExpression) {
+      if ((context.decoratorTarget as DecoratorExpressionNode).parent !== entity.node) {
+        return;
+      }
+    }
+  }
+
   setScopedDecoratorData(context, $clientName, clientNameKey, entity, value, scope);
 }
 

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

@@ -13,6 +13,7 @@ import { beforeEach, describe, it } from "vitest";
 import {
   getAccess,
   getClient,
+  getClientNameOverride,
   getOperationGroup,
   getUsage,
   listClients,
@@ -2350,4 +2351,68 @@ describe("typespec-client-generator-core: decorators", () => {
       });
     });
   });
+
+  describe("@clientName", () => {
+    it("carry over", async () => {
+      const { Test1, Test2, func1, func2 } = (await runner.compile(`
+        @service({})
+        @test namespace MyService {
+          @test
+          @clientName("Test1Rename")
+          model Test1{}
+
+          @test
+          model Test2 is Test1{}
+
+          @test
+          @route("/func1")
+          @clientName("func1Rename")
+          op func1(): void;
+
+          @test
+          @route("/func2")
+          op func2 is func1;
+        }
+      `)) as { Test1: Model; Test2: Model; func1: Operation; func2: Operation };
+
+      strictEqual(getClientNameOverride(runner.context, Test1), "Test1Rename");
+      strictEqual(getClientNameOverride(runner.context, Test2), undefined);
+      strictEqual(getClientNameOverride(runner.context, func1), "func1Rename");
+      strictEqual(getClientNameOverride(runner.context, func2), undefined);
+    });
+
+    it("augment carry over", async () => {
+      const { Test1, Test2, func1, func2 } = (await runner.compileWithCustomization(
+        `
+        @service({})
+        @test namespace MyService {
+          @test
+          model Test1{}
+
+          @test
+          model Test2 is Test1{}
+
+          @test
+          @route("/func1")
+          op func1(): void;
+
+          @test
+          @route("/func2")
+          op func2 is func1;
+        }
+      `,
+        `
+        namespace Customizations;
+
+        @@clientName(MyService.Test1, "Test1Rename");
+        @@clientName(MyService.func1, "func1Rename");
+      `
+      )) as { Test1: Model; Test2: Model; func1: Operation; func2: Operation };
+
+      strictEqual(getClientNameOverride(runner.context, Test1), "Test1Rename");
+      strictEqual(getClientNameOverride(runner.context, Test2), undefined);
+      strictEqual(getClientNameOverride(runner.context, func1), "func1Rename");
+      strictEqual(getClientNameOverride(runner.context, func2), undefined);
+    });
+  });
 });