Add pipe-delimited extensible union array test case to encode/array spec

[Copilot]

Adding ArrayEncoding test case with enum

• Add Color enum definition to main.tsp
• Add PipeDelimitedArrayEnumElementProperty model with enum array
• Add pipeDelimitedEnumElement operation with proper scenario documentation
• Update mockapi.ts to add server-side test for the new enum scenario
• Run build and tests to validate changes
• Verify all scenarios and mock APIs are valid
• Convert Color from enum to extensible union per review feedback
• Update documentation to correctly reference extensible union
• Add changelog entry using pnpm change add
• Run pnpm format to ensure code formatting is correct

Original prompt

---

This section details on the original issue you should resolve

<issue_title>http-specs, add test case for ArrayEncoding with enum</issue_title>
<issue_description>Add a new test case op pipeDelimitedEnumElement(@body body: PipeDelimitedArrayEnumElementProperty): PipeDelimitedArrayEnumElementProperty;) to https://github.com/microsoft/typespec/blob/main/packages/http-specs/specs/encode/array/main.tsp

The scenario on wire would be same as pipeDelimited.

Just the type be e.g.

model PipeDelimitedArrayEnumElementProperty {
  @encode(ArrayEncoding.pipeDelimited)
  value: Color[];
}
```</issue_description>

## Comments on the Issue (you are @copilot in this section)

<comments>
</comments>

• Fixes http-specs, add test case for ArrayEncoding with enum #9329

---

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commit: 36029ef

[weidongxu-microsoft]

@copilot

Please add changelog
pnpm change add

[Copilot]

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[Copilot]

@copilot

Please add changelog
...

Added changelog entry in commit aab8d3a.

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  • Triggering command: /usr/local/bin/node node /home/REDACTED/work/typespec/typespec/website/node_modules/.bin/../astro/astro.js build node nts/�� ebsite/src/content/docs/docs/emitters/openapi3/reference . node_modules/@npmcli/run-script/../../website/src/content/docs/docs/emitters/protobuf/reference --import @typespec/librar-c ents/reference sh -c astro check --minimumFailingSeverity hint && ast--filter node .0_tmp_3357/node_modules/pnpm/dist/node-gyp-bin/node -p . && pnpm lish node /snap/bin/sh node (dns block)

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[weidongxu-microsoft]

@copilot

run pnpm format

double check instructions in https://github.com/microsoft/typespec/blob/main/.github/prompts/testserver-generation.md

[github-actions]

All changed packages have been documented.

• ✅ @typespec/http-specs

Show changes

@typespec/http-specs - feature ✏️

Add test case for ArrayEncoding with extensible union

[Copilot]

@copilot

run pnpm format
...

Format has been applied (commit bf398ef). All validation checks pass:

• ✅ pnpm build
• ✅ pnpm validate-mock-apis
• ✅ pnpm regen-docs

The implementation follows the testserver-generation.md guidelines.

Warning

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I tried to connect to the following addresses, but was blocked by firewall rules:

• telemetry.astro.build
  • Triggering command: /usr/local/bin/node node /home/REDACTED/work/typespec/typespec/website/node_modules/.bin/../astro/astro.js build sh cal/�� ebsite/src/content/docs/docs/emitters/openapi3/reference sed pec/node_modules/.bin/node warn-as-error --sh sh /bin/esbuild node p/no�� validate-scenarios /bin/esbuild .0_tmp_3350/node_modules/pnpm/dist/node-gyp-bin/node /library-linter sh node tools/pnpm/10.23tsx ./.scripts/regen-compiler-docs.ts tp/reference (dns block)

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[tadelesh]

Replaced with #9390.