feat(openapi3): add @pageItems decorator when x-ms-list-page-items extension is present

[Copilot]

The OpenAPI importer wasn't generating the @pageItems decorator for array properties annotated with x-ms-list-page-items: true.

Changes

• Modified getDecoratorsForSchema to detect x-ms-list-page-items: true and add @pageItems decorator
• Both @extension and @pageItems decorators are now applied when the extension is present
• Added test coverage for true/false/absent cases

Example

Input OpenAPI:

WidgetList:
  type: object
  properties:
    value:
      type: array
      items:
        $ref: '#/components/schemas/Widget'
      x-ms-list-page-items: true

Generated TypeSpec:

model WidgetList {
  @extension("x-ms-list-page-items", true) @pageItems value: Widget[];
}

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Add support for importing the pageItems decorator based on the relevant OpenAPI extension</issue_title>
<issue_description>### Clear and concise description of the problem

Related https://github.com/microsoft/openai-openapi-pr/issues/568

Based on the following OpenAPI description, we should get the following TypeSpec definition imported

openapi: 3.0.0
info:
  title: Widget Service
  version: 0.0.0
tags:
  - name: Widgets
paths:
  /widgets:
    get:
      operationId: Widgets_list
      description: List widgets
      parameters: []
      responses:
        '200':
          description: The request has succeeded.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/WidgetList'
        default:
          description: An unexpected error response.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
      tags:
        - Widgets
    post:
      operationId: Widgets_create
      description: Create a widget
      parameters: []
      responses:
        '200':
          description: The request has succeeded.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Widget'
        default:
          description: An unexpected error response.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
      tags:
        - Widgets
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/Widget'
  /widgets/{id}:
    get:
      operationId: Widgets_read
      description: Read widgets
      parameters:
        - name: id
          in: path
          required: true
          schema:
            type: string
            readOnly: true
      responses:
        '200':
          description: The request has succeeded.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Widget'
        default:
          description: An unexpected error response.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
      tags:
        - Widgets
    patch:
      operationId: Widgets_update
      description: Update a widget
      parameters:
        - name: id
          in: path
          required: true
          schema:
            type: string
            readOnly: true
      responses:
        '200':
          description: The request has succeeded.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Widget'
        default:
          description: An unexpected error response.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
      tags:
        - Widgets
      requestBody:
        required: true
        content:
          application/merge-patch+json:
            schema:
              $ref: '#/components/schemas/WidgetMergePatchUpdate'
    delete:
      operationId: Widgets_delete
      description: Delete a widget
      parameters:
        - name: id
          in: path
          required: true
          schema:
            type: string
            readOnly: true
      responses:
        '204':
          description: 'There is no content to send for this request, but the headers may be useful. '
        default:
          description: An unexpected error response.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
      tags:
        - Widgets
  /widgets/{id}/analyze:
    post:
      operationId: Widgets_analyze
      description: Analyze a widget
      parameters:
        - name: id
          in: path
          required: true
          schema:
            type: string
            readOnly: true
      responses:
        '200':
          description: The request has succeeded.
          content:
            text/plain:
              schema:
                type: string
        default:
          description: An unexpected error response.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
      tags:
        - Widgets
components:
  schemas:
    Error:
      type: object
      required:
        - code
        - message
      properties:
        code:
          type: integer
          format: int32
        message:
          type: string
    Widget:
      type: object
      required:
        - id
        - weight
        - color
      properties:
        id:
          type: string
          readOnly: true
        weight:
          type: integer
          format: int32
        color:
          type: strin...

</details>



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- Fixes microsoft/typespec#9614

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commit: 513ee13

[github-actions]

All changed packages have been documented.

• ✅ @typespec/openapi3

Show changes

@typespec/openapi3 - feature ✏️

importer - Add support for x-ms-list-page-items extension to @pageItems decorator

[azure-sdk]

You can try these changes here

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