Add test cases for @clientDefaultValue decorator (#3635)

- [x] Create new directory for client-default-value test cases
- [x] Add test case 1: @clientDefaultValue for model property
- [x] Add test case 2: @clientDefaultValue for operation parameter
- [x] Add test case 3: @clientDefaultValue for first path segment in
multi-segment path
- [x] Add main.tsp file with all test scenarios
- [x] Add mockapi.ts file with mock API definitions
- [x] Fix mockapi.ts to use correct format (query instead of params,
json() helper, correct scenario names)
- [x] Fix suppress directive placement to be directly above decorators
- [x] Make segment1 parameter required (not optional)
- [x] Fix changelog location to .chronus/changes/ directory
- [x] Add backticks around decorator references in documentation
- [x] Update spec-summary.md with client-default-value documentation
- [x] Fix Prettier formatting for spec-summary.md
- [x] Fix code formatting with Prettier
- [x] Run final code review - No issues found
- [x] Run security checks - No vulnerabilities found

## Summary

Successfully added three comprehensive test cases for the
`@clientDefaultValue` decorator:

### Test Case 1: Model Property
- Tests `@clientDefaultValue` on model properties
- Includes numeric (timeout=30), string (tier="standard"), and boolean
(retry=true) default values
- Uses PUT operation with request/response body validation

### Test Case 2: Operation Parameter  
- Tests `@clientDefaultValue` on operation parameters
- Includes query parameters with default values (pageSize=10,
format="json")
- Uses GET operation with query parameter validation

### Test Case 3: Path Parameter with Multiple Segments
- Tests `@clientDefaultValue` on the first path segment in a 2-segment
path
- Path structure: `/path-parameter/{segment1}/{segment2}`
- First segment has default value "default-segment1" and is required
- Second segment is required without default

All test cases follow existing repository patterns and conventions.

<!-- START COPILOT ORIGINAL PROMPT -->



<details>

<summary>Original prompt</summary>

> 
> ----
> 
> *This section details on the original issue you should resolve*
> 
> <issue_title>[spector] add new case for decorator
`@clientDefaultValue`</issue_title>
> <issue_description>Context:
> 
> `@clientDefaultValue` definition is here
https://github.com/Azure/typespec-azure/blob/32292dabd9a4741b02a211fe3838a7279961f690/website/src/content/docs/docs/libraries/typespec-client-generator-core/reference/decorators.md?plain=1#L1154-L1168
> 
> Goal:
> Add test case in folder
https://github.com/Azure/typespec-azure/tree/main/packages/azure-http-specs/specs/azure/client-generator-core
> 
> Ask:
> - Add 3 cases:
> 1. for model property
> 2. for operation parameter
> 3. this case has 2 path segments and add client default value for
first path segment.</issue_description>
> 
> ## Comments on the Issue (you are @copilot in this section)
> 
> <comments>
> </comments>
> 


</details>



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- Fixes #3633

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---------

Co-authored-by: copilot-swe-agent[bot] <[email protected]>
Co-authored-by: msyyc <[email protected]>
Co-authored-by: Yuchao Yan <[email protected]>
Co-authored-by: tadelesh <[email protected]>

Author: 3 people

.chronus/changes/add-clientdefaultvalue-test-cases-2025-12-11.md

@@ -0,0 +1,7 @@
+---
+changeKind: feature
+packages:
+  - "@azure-tools/azure-http-specs"
+---
+
+Add test cases for `@clientDefaultValue` decorator.

packages/azure-http-specs/spec-summary.md

@@ -316,6 +316,59 @@ client.getStandalone();
 client.deleteStandalone();
 ```
 
+### Azure_ClientGenerator_Core_ClientDefaultValue_getOperationParameter
+
+- Endpoint: `get /azure/client-generator-core/client-default-value/operation-parameter`
+
+Test case 2: `@clientDefaultValue` for operation parameter.
+This scenario tests that client default values are correctly applied to operation parameters.
+
+Expected query parameter:
+name: "test"
+pageSize: 10 (default)
+format: "json" (default)
+
+Expected response: 204 No Content
+
+### Azure_ClientGenerator_Core_ClientDefaultValue_getPathParameter
+
+- Endpoint: `get /azure/client-generator-core/client-default-value/path-parameter/{segment1}/{segment2}`
+
+Test case 3: `@clientDefaultValue` for first path segment.
+This scenario has 2 path segments and tests client default value on the first segment.
+
+Expected path parameters:
+segment1: "default-segment1" (default)
+segment2: "segment2"
+
+Expected response: 204 No Content
+
+### Azure_ClientGenerator_Core_ClientDefaultValue_putModelProperty
+
+- Endpoint: `put /azure/client-generator-core/client-default-value/model-property`
+
+Test case 1: `@clientDefaultValue` for model property.
+This scenario tests that client default values are correctly applied to model properties.
+
+Expected input body:
+
+```json
+{
+  "name": "test"
+}
+```
+
+Expected response body:
+
+```json
+{
+  "name": "test",
+  "timeout": 30,
+  "tier": "standard",
+  "retry": true
+}
+```
+
 ### Azure_ClientGenerator_Core_ClientLocation_MoveMethodParameterToClient
 
 - Endpoint: `get /azure/client-generator-core/client-location/blob`

packages/azure-http-specs/specs/azure/client-generator-core/client-default-value/main.tsp

@@ -0,0 +1,116 @@
+import "@typespec/http";
+import "@typespec/spector";
+import "@azure-tools/typespec-client-generator-core";
+
+using Http;
+using Azure.ClientGenerator.Core;
+using Spector;
+
+@doc("Test for `@clientDefaultValue` decorator.")
+@scenarioService("/azure/client-generator-core/client-default-value")
+@global.Azure.ClientGenerator.Core.clientNamespace(
+  "azure.clientgenerator.core.clientdefaultvalue",
+  "java"
+)
+@global.Azure.ClientGenerator.Core.clientNamespace(
+  "specs.azure.clientgenerator.core.clientdefaultvalue",
+  "python"
+)
+namespace _Specs_.Azure.ClientGenerator.Core.ClientDefaultValue;
+
+@doc("Model with client default values on properties.")
+model ModelWithDefaultValues {
+  @doc("Name property with no default value.")
+  name: string;
+
+  #suppress "@azure-tools/typespec-azure-core/no-legacy-usage" "Testing legacy decorator"
+  @doc("Timeout property with client default value of 30.")
+  @global.Azure.ClientGenerator.Core.Legacy.clientDefaultValue(30)
+  timeout?: int32;
+
+  #suppress "@azure-tools/typespec-azure-core/no-legacy-usage" "Testing legacy decorator"
+  @doc("Tier property with client default value of 'standard'.")
+  @global.Azure.ClientGenerator.Core.Legacy.clientDefaultValue("standard")
+  tier?: string;
+
+  #suppress "@azure-tools/typespec-azure-core/no-legacy-usage" "Testing legacy decorator"
+  @doc("Retry property with client default value of true.")
+  @global.Azure.ClientGenerator.Core.Legacy.clientDefaultValue(true)
+  retry?: boolean;
+}
+
+@scenario
+@route("/model-property")
+@scenarioDoc("""
+  Test case 1: `@clientDefaultValue` for model property.
+  This scenario tests that client default values are correctly applied to model properties.
+  
+  Expected input body:
+  ```json
+  {
+    "name": "test"
+  }
+  ```
+  
+  Expected response body:
+  ```json
+  {
+    "name": "test",
+    "timeout": 30,
+    "tier": "standard",
+    "retry": true
+  }
+  ```
+  """)
+@put
+op putModelProperty(@body body: ModelWithDefaultValues): ModelWithDefaultValues;
+
+@scenario
+@route("/operation-parameter")
+@scenarioDoc("""
+  Test case 2: `@clientDefaultValue` for operation parameter.
+  This scenario tests that client default values are correctly applied to operation parameters.
+  
+  Expected query parameter:
+  name: "test"
+  pageSize: 10 (default)
+  format: "json" (default)
+  
+  Expected response: 204 No Content
+  """)
+@get
+op getOperationParameter(
+  @query name: string,
+
+  #suppress "@azure-tools/typespec-azure-core/no-legacy-usage" "Testing legacy decorator"
+  @global.Azure.ClientGenerator.Core.Legacy.clientDefaultValue(10)
+  @query
+  pageSize?: int32,
+
+  #suppress "@azure-tools/typespec-azure-core/no-legacy-usage" "Testing legacy decorator"
+  @global.Azure.ClientGenerator.Core.Legacy.clientDefaultValue("json")
+  @query
+  format?: string,
+): void;
+
+@scenario
+@route("/path-parameter/{segment1}/{segment2}")
+@scenarioDoc("""
+  Test case 3: `@clientDefaultValue` for first path segment.
+  This scenario has 2 path segments and tests client default value on the first segment.
+  
+  Expected path parameters:
+  segment1: "default-segment1" (default)
+  segment2: "segment2"
+  
+  Expected response: 204 No Content
+  """)
+@get
+op getPathParameter(
+  #suppress "@azure-tools/typespec-azure-core/no-legacy-usage" "Testing legacy decorator"
+  @global.Azure.ClientGenerator.Core.Legacy.clientDefaultValue("default-segment1")
+  @path
+  segment1: string,
+
+  @path segment2: string,
+): void;

packages/azure-http-specs/specs/azure/client-generator-core/client-default-value/mockapi.ts

@@ -0,0 +1,55 @@
+import { json, passOnSuccess, ScenarioMockApi } from "@typespec/spec-api";
+
+export const Scenarios: Record<string, ScenarioMockApi> = {};
+
+Scenarios.Azure_ClientGenerator_Core_ClientDefaultValue_putModelProperty = passOnSuccess([
+  {
+    uri: "/azure/client-generator-core/client-default-value/model-property",
+    method: "put",
+    request: {
+      body: json({
+        name: "test",
+      }),
+    },
+    response: {
+      status: 200,
+      body: json({
+        name: "test",
+        timeout: 30,
+        tier: "standard",
+        retry: true,
+      }),
+    },
+    kind: "MockApiDefinition",
+  },
+]);
+
+Scenarios.Azure_ClientGenerator_Core_ClientDefaultValue_getOperationParameter = passOnSuccess([
+  {
+    uri: "/azure/client-generator-core/client-default-value/operation-parameter",
+    method: "get",
+    request: {
+      query: {
+        name: "test",
+        pageSize: 10,
+        format: "json",
+      },
+    },
+    response: {
+      status: 204,
+    },
+    kind: "MockApiDefinition",
+  },
+]);
+
+Scenarios.Azure_ClientGenerator_Core_ClientDefaultValue_getPathParameter = passOnSuccess([
+  {
+    uri: "/azure/client-generator-core/client-default-value/path-parameter/default-segment1/segment2",
+    method: "get",
+    request: {},
+    response: {
+      status: 204,
+    },
+    kind: "MockApiDefinition",
+  },
+]);