feat: add cross-language Spector tests for dollar-sign query params and discriminator without subtypes

.chronus/changes/feat-cross-language-spector-tests-2026-4-29-13-38-16.md

@@ -0,0 +1,7 @@
+---
+changeKind: feature
+packages:
+  - "@typespec/http-specs"
+---
+
+add test for discriminator model without subtypes and query params with `$` prefixes

packages/http-client-js/.testignore

@@ -13,3 +13,7 @@ type/union/discriminated
 # Multipart - https://github.com/microsoft/typespec/issues/9155
 
 payload/multipart
+
+# Body root issues - https://github.com/microsoft/typespec/issues/10877
+
+parameters/body-root

packages/http-specs/spec-summary.md

@@ -1455,6 +1455,22 @@ Expected request body:
 { "name": "foo" }
 ```
 
+### Parameters_BodyRoot_nested
+
+- Endpoint: `post /parameters/body-root/nested`
+
+Test case for a `@bodyRoot` parameter nested inside a wrapper model.
+
+Emitters must resolve the accessor path through the wrapper (e.g.
+`body.bodyRootParameters`) rather than referencing the property name
+directly.
+
+Expected request body:
+
+```json
+{ "category": "widget", "linkType": "hard", "wasSuccessful": true }
+```
+
 ### Parameters_CollectionFormat_Header_csv
 
 - Endpoint: `get /parameters/collection-format/header/csv`
@@ -1534,6 +1550,18 @@ Second request path:
 
 Expect to handle a constant value for query and mock api returns nothing
 
+### Parameters_Query_SpecialChar_dollarSign
+
+- Endpoint: `get /parameters/query/special-char/dollarSign`
+
+Send a request with a dollar-sign prefixed`$filter` query parameter.
+
+Expected query parameter:
+
+- `$filter` = "status eq 'active'"
+
+Expected response status code: 204
+
 ### Parameters_Spread_Alias_spreadAsRequestBody
 
 - Endpoint: `put /parameters/spread/alias/request-body`
@@ -6226,6 +6254,18 @@ Expected response body:
 { "wingspan": 1, "kind": "sparrow" }
 ```
 
+### Type_Model_Inheritance_SingleDiscriminator_getNoSubtypesModel
+
+- Endpoint: `get /type/model/inheritance/single-discriminator/no-subtypes/model`
+
+Generate and receive a discriminated model that has no defined subtypes.
+The base model declares a discriminator but no models extend it.
+Expected response body:
+
+```json
+{ "kind": "salmon", "size": 10 }
+```
+
 ### Type_Model_Inheritance_SingleDiscriminator_getRecursiveModel
 
 - Endpoint: `get /type/model/inheritance/single-discriminator/recursivemodel`
@@ -6278,6 +6318,17 @@ Expected input body:
 { "wingspan": 1, "kind": "sparrow" }
 ```
 
+### Type_Model_Inheritance_SingleDiscriminator_putNoSubtypesModel
+
+- Endpoint: `put /type/model/inheritance/single-discriminator/no-subtypes/model`
+
+Send a discriminated model that has no defined subtypes.
+Expected input body:
+
+```json
+{ "kind": "salmon", "size": 10 }
+```
+
 ### Type_Model_Inheritance_SingleDiscriminator_putRecursiveModel
 
 - Endpoint: `put /type/model/inheritance/single-discriminator/recursivemodel`

packages/http-specs/specs/parameters/body-root/main.tsp

@@ -0,0 +1,36 @@
+import "@typespec/http";
+import "@typespec/spector";
+
+using Http;
+using Spector;
+
+@doc("Test for @bodyRoot parameter patterns.")
+@scenarioService("/parameters/body-root")
+namespace Parameters.BodyRoot;
+
+model BodyRootModel {
+  category?: string;
+  linkType?: string;
+  wasSuccessful?: boolean;
+}
+
+@scenario
+@scenarioDoc("""
+  Test case for a \`@bodyRoot\` parameter nested inside a wrapper model.
+
+  Emitters must resolve the accessor path through the wrapper (e.g.
+  \`body.bodyRootParameters\`) rather than referencing the property name
+  directly.
+
+  Expected request body:
+  \`\`\`json
+  { "category": "widget", "linkType": "hard", "wasSuccessful": true }
+  \`\`\`
+  """)
+@route("/nested")
+@post
+op nested(
+  body: {
+    @bodyRoot bodyRootParameters: BodyRootModel;
+  },
+): NoContentResponse;

packages/http-specs/specs/parameters/body-root/mockapi.ts

@@ -0,0 +1,19 @@
+import { json, passOnSuccess, ScenarioMockApi } from "@typespec/spec-api";
+
+export const Scenarios: Record<string, ScenarioMockApi> = {};
+
+Scenarios.Parameters_BodyRoot_nested = passOnSuccess({
+  uri: "/parameters/body-root/nested",
+  method: "post",
+  request: {
+    body: json({
+      category: "widget",
+      linkType: "hard",
+      wasSuccessful: true,
+    }),
+  },
+  response: {
+    status: 204,
+  },
+  kind: "MockApiDefinition",
+});

packages/http-specs/specs/parameters/query/main.tsp

@@ -20,3 +20,23 @@ interface Constant {
     queryParam: "constantValue",
   ): void;
 }
+
+@doc("Special char query parameter verification")
+@route("/special-char")
+interface SpecialChar {
+  @scenario
+  @scenarioDoc("""
+    Send a request with a dollar-sign prefixed`$filter` query parameter.
+
+    Expected query parameter:
+    - `$filter` = "status eq 'active'"
+
+    Expected response status code: 204
+    """)
+  @route("/dollarSign")
+  @get
+  dollarSign(
+    @query("$filter")
+    filter: string,
+  ): void;
+}

packages/http-specs/specs/parameters/query/mockapi.ts

@@ -13,3 +13,15 @@ Scenarios.Parameters_Query_Constant_post = passOnSuccess({
   },
   kind: "MockApiDefinition",
 });
+
+Scenarios.Parameters_Query_SpecialChar_dollarSign = passOnSuccess({
+  uri: "/parameters/query/special-char/dollar-sign",
+  method: "get",
+  request: {
+    query: { $filter: "status eq 'active'" },
+  },
+  response: {
+    status: 204,
+  },
+  kind: "MockApiDefinition",
+});

packages/http-specs/specs/type/model/inheritance/single-discriminator/main.tsp

@@ -49,6 +49,13 @@ model TRex extends Dinosaur {
   kind: "t-rex";
 }
 
+@doc("A discriminated model with no defined subtypes. The discriminator is declared but no models extend it.")
+@discriminator("kind")
+model Fish {
+  kind: string;
+  size: int32;
+}
+
 @scenario
 @route("/model")
 @scenarioDoc("""
@@ -170,3 +177,28 @@ op getWrongDiscriminator(): Bird;
   """)
 @get
 op getLegacyModel(): Dinosaur;
+
+@scenario
+@route("/no-subtypes/model")
+@scenarioDoc("""
+  Generate and receive a discriminated model that has no defined subtypes.
+  The base model declares a discriminator but no models extend it.
+  Expected response body:
+  ```json
+  {"kind": "salmon", "size": 10}
+  ```
+  """)
+@get
+op getNoSubtypesModel(): Fish;
+
+@scenario
+@route("/no-subtypes/model")
+@scenarioDoc("""
+  Send a discriminated model that has no defined subtypes.
+  Expected input body:
+  ```json
+  {"kind": "salmon", "size": 10}
+  ```
+  """)
+@put
+op putNoSubtypesModel(@body input: Fish): NoContentResponse;

packages/http-specs/specs/type/model/inheritance/single-discriminator/mockapi.ts

@@ -101,3 +101,31 @@ Scenarios.Type_Model_Inheritance_SingleDiscriminator_getLegacyModel = passOnSucc
   },
   kind: "MockApiDefinition",
 });
+
+const noSubtypesBody = {
+  kind: "salmon",
+  size: 10,
+};
+
+Scenarios.Type_Model_Inheritance_SingleDiscriminator_getNoSubtypesModel = passOnSuccess({
+  uri: "/type/model/inheritance/single-discriminator/no-subtypes/model",
+  method: "get",
+  request: {},
+  response: {
+    status: 200,
+    body: json(noSubtypesBody),
+  },
+  kind: "MockApiDefinition",
+});
+
+Scenarios.Type_Model_Inheritance_SingleDiscriminator_putNoSubtypesModel = passOnSuccess({
+  uri: "/type/model/inheritance/single-discriminator/no-subtypes/model",
+  method: "put",
+  request: {
+    body: json(noSubtypesBody),
+  },
+  response: {
+    status: 204,
+  },
+  kind: "MockApiDefinition",
+});