[BUG] enum issue when using generated dart

[boojongmin]

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• What's the version of OpenAPI Generator used?
• Have you search for related issues/PRs?
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Description

I meet a bug when using a generated dart source.

because json serializer can't serialize enum type directly.
so I modify code like below image.(add '.value')

would you fix this bug?

openapi-generator version

4.1.3

OpenAPI declaration file content or url

[wing328]

so I modify code like below image.(add '.value')

@boojongmin can you please file a PR with the suggested fix?

dart2 templates can be found in https://github.com/OpenAPITools/openapi-generator/tree/master/modules/openapi-generator/src/main/resources/dart2

[b1rdG]

Hi,

On the version 4.3.1 the serialize function delegate on dart convert library json.encode(). It return an error because serializing this enums because the enum is not "encodable" (is not a number, boolean, string, null, list or a map), so the encode() method looks for a toJson() on the Object passed:

  /// If [toEncodable] is omitted, it defaults to a function that returns the
  /// result of calling `.toJson()` on the unencodable object.

And, the enum objects doesn't have this method...

[b1rdG]

Hi I created a PR #6111

[agilob]

This should be closed @b1rdG @wing328