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• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
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Description

In typescript-fetch and java native there have to be serializers for date-time parameters. In the dotnetcore generator the correct serialization is already done.

openapi-generator version

OpenAPI declaration file content or url

openapi: 3.0.3
info:
  title: date-test
  version: 1.0.0
paths:
  /test:
    get:
      operationId: test
      parameters:
        - name: a
          in: query
          schema:
            type: string
            format: date-time
      responses:
        '200':
          description: OK
          content:
            text/plain:
              schema:
                type: string

Generation Details

Generate typescript with typescript-fetch, generate java with native and java8.

Steps to reproduce

Related issues/PRs

Suggest a fix

Typescript:

In the generated method queryString in runtime.ts there has to be an additional handling of Date like

if (value instanceof Date) {
    return `${encodeURIComponent(fullKey)}=${encodeURIComponent(value.toISOString())}`;
}

Java:
In the generated method valueToString there has to be used a serializer like

if (value instanceof OffsetDateTime) {
      return ((OffsetDateTime) value).format(DateTimeFormatter.ISO_OFFSET_DATE_TIME);
}