Add spector case for extensible enum with special word member names

.chronus/changes/copilot-add-special-words-enum-2026-02-26-12-04-50.md

@@ -0,0 +1,7 @@
+---
+changeKind: feature
+packages:
+  - "@typespec/http-specs"
+---
+
+Add spector case for extensible enum with special word member names

packages/http-specs/spec-summary.md

@@ -3977,6 +3977,13 @@ Expected header parameters:
 
 Check we recognize Repeatability-Request-ID and Repeatability-First-Sent.
 
+### SpecialWords_ExtensibleStrings_putExtensibleStringValue
+
+- Endpoint: `put /special-words/extensible-strings/string`
+
+Verify that enum members with special word names can be sent and received properly.
+Send 'class' and expect the same value back.
+
 ### SpecialWords_ModelProperties_dictMethods
 
 - Endpoint: `get /special-words/model-properties/dict-methods`

packages/http-specs/specs/special-words/main.tsp

@@ -289,3 +289,58 @@ namespace ModelProperties {
   @route("list")
   op withList(@body body: ModelWithList): void;
 }
+
+/**
+ * Verify enum member names that are special words using extensible enum (union).
+ */
+union ExtensibleString {
+  string,
+  and: "and",
+  as: "as",
+  assert: "assert",
+  async: "async",
+  await: "await",
+  break: "break",
+  class: "class",
+  constructor: "constructor",
+  continue: "continue",
+  def: "def",
+  del: "del",
+  elif: "elif",
+  `else`: "else",
+  except: "except",
+  exec: "exec",
+  finally: "finally",
+  for: "for",
+  from: "from",
+  global: "global",
+  `if`: "if",
+  `import`: "import",
+  in: "in",
+  `is`: "is",
+  lambda: "lambda",
+  not: "not",
+  or: "or",
+  pass: "pass",
+  raise: "raise",
+  `return`: "return",
+  try: "try",
+  while: "while",
+  with: "with",
+  yield: "yield",
+}
+
+/**
+ * Verify enum member names that are special words.
+ */
+@route("/extensible-strings")
+interface ExtensibleStrings {
+  @scenario
+  @scenarioDoc("""
+    Verify that enum members with special word names can be sent and received properly.
+    Send 'class' and expect the same value back.
+    """)
+  @put
+  @route("/string")
+  putExtensibleStringValue(@body body: ExtensibleString): ExtensibleString;
+}

packages/http-specs/specs/special-words/mockapi.ts

@@ -1,4 +1,4 @@
-import { json, passOnSuccess, ScenarioMockApi } from "@typespec/spec-api";
+import { json, MockRequest, passOnSuccess, ScenarioMockApi } from "@typespec/spec-api";
 
 export const Scenarios: Record<string, ScenarioMockApi> = {};
 
@@ -419,3 +419,22 @@ Scenarios.SpecialWords_Parameters_cancellationToken = createParametersTests(
   },
   "cancellationToken",
 );
+
+Scenarios.SpecialWords_ExtensibleStrings_putExtensibleStringValue = passOnSuccess({
+  uri: `/special-words/extensible-strings/string`,
+  method: "put",
+  request: {
+    body: json("class"),
+  },
+  response: {
+    status: 200,
+    body: json("class"),
+  },
+  handler: (req: MockRequest) => {
+    return {
+      status: 200,
+      body: json(req.body),
+    };
+  },
+  kind: "MockApiDefinition",
+});