Add CSV encoding tests for enum and extensible enum arrays

.chronus/changes/copilot-add-enum-array-test-2026-0-15-14-32-1.md

@@ -0,0 +1,7 @@
+---
+changeKind: feature
+packages:
+  - "@typespec/http-specs"
+---
+
+Add array encoding test for enum and extensible enum arrays.

packages/http-specs/spec-summary.md

@@ -138,6 +138,174 @@ Expected response body:
 }
 ```
 
+### Encode_Array_Property_enumCommaDelimited
+
+- Endpoint: `post /encode/array/property/enum/comma-delimited`
+
+Test operation with request and response model contains an enum array property with commaDelimited encode.
+Expected request body:
+
+```json
+{
+  "value": "blue,red,green"
+}
+```
+
+Expected response body:
+
+```json
+{
+  "value": "blue,red,green"
+}
+```
+
+### Encode_Array_Property_enumNewlineDelimited
+
+- Endpoint: `post /encode/array/property/enum/newline-delimited`
+
+Test operation with request and response model contains an enum array property with newlineDelimited encode.
+Expected request body:
+
+```json
+{
+  "value": "blue\nred\ngreen"
+}
+```
+
+Expected response body:
+
+```json
+{
+  "value": "blue\nred\ngreen"
+}
+```
+
+### Encode_Array_Property_enumPipeDelimited
+
+- Endpoint: `post /encode/array/property/enum/pipe-delimited`
+
+Test operation with request and response model contains an enum array property with pipeDelimited encode.
+Expected request body:
+
+```json
+{
+  "value": "blue|red|green"
+}
+```
+
+Expected response body:
+
+```json
+{
+  "value": "blue|red|green"
+}
+```
+
+### Encode_Array_Property_enumSpaceDelimited
+
+- Endpoint: `post /encode/array/property/enum/space-delimited`
+
+Test operation with request and response model contains an enum array property with spaceDelimited encode.
+Expected request body:
+
+```json
+{
+  "value": "blue red green"
+}
+```
+
+Expected response body:
+
+```json
+{
+  "value": "blue red green"
+}
+```
+
+### Encode_Array_Property_extensibleEnumCommaDelimited
+
+- Endpoint: `post /encode/array/property/extensible-enum/comma-delimited`
+
+Test operation with request and response model contains an extensible enum (union) array property with commaDelimited encode.
+Expected request body:
+
+```json
+{
+  "value": "blue,red,green"
+}
+```
+
+Expected response body:
+
+```json
+{
+  "value": "blue,red,green"
+}
+```
+
+### Encode_Array_Property_extensibleEnumNewlineDelimited
+
+- Endpoint: `post /encode/array/property/extensible-enum/newline-delimited`
+
+Test operation with request and response model contains an extensible enum (union) array property with newlineDelimited encode.
+Expected request body:
+
+```json
+{
+  "value": "blue\nred\ngreen"
+}
+```
+
+Expected response body:
+
+```json
+{
+  "value": "blue\nred\ngreen"
+}
+```
+
+### Encode_Array_Property_extensibleEnumPipeDelimited
+
+- Endpoint: `post /encode/array/property/extensible-enum/pipe-delimited`
+
+Test operation with request and response model contains an extensible enum (union) array property with pipeDelimited encode.
+Expected request body:
+
+```json
+{
+  "value": "blue|red|green"
+}
+```
+
+Expected response body:
+
+```json
+{
+  "value": "blue|red|green"
+}
+```
+
+### Encode_Array_Property_extensibleEnumSpaceDelimited
+
+- Endpoint: `post /encode/array/property/extensible-enum/space-delimited`
+
+Test operation with request and response model contains an extensible enum (union) array property with spaceDelimited encode.
+Expected request body:
+
+```json
+{
+  "value": "blue red green"
+}
+```
+
+Expected response body:
+
+```json
+{
+  "value": "blue red green"
+}
+```
+
 ### Encode_Array_Property_newlineDelimited
 
 - Endpoint: `post /encode/array/property/newline-delimited`