[dart-dio-next] Don't use encodeCollectionQueryParameter on maps

[ahmednfwela]

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CC: @jaumard @josh-burton @amondnet @sbu-WBT @kuhnroyal @agilob

[kuhnroyal]

There doesn't seem to be a sample for this. What are you expecting to be serialized when you pass a map as parameter?

[agilob]

What are the consequences of encoding maps and not encoding maps?

[kuhnroyal]

Well, currently it throws an error. So we can:

1. not specifically handle it (that what the current changes do)
2. somehow encode it but this probably requires full deepObject support, I don't see this happening soon

So I am fine with just not handling it and let it run through the old encodeQueryParameter. Not sure what the output is but it won't throw.

[ahmednfwela]

using encodeQueryParameter returns a raw map that is then passed to dio, and dio handles it correctly as expected in the form of:
field[key]=value

[agilob]

Would be nice to have a test or sample to persist this behaviour

[kuhnroyal]

Please attach a spec snippet for this, we need to add this to the sample spec and add tests.

[agilob]

Since encoding map is a quite common scenario, should existing spec be updated to include maps?

[kuhnroyal]

Yea, I was thinking here: https://github.com/OpenAPITools/openapi-generator/blob/master/modules/openapi-generator/src/test/resources/3_0/petstore-with-fake-endpoints-models-for-testing.yaml#L1048
@wing328 What do you think?

[wing328]

Yes, please update https://github.com/OpenAPITools/openapi-generator/blob/master/modules/openapi-generator/src/test/resources/3_0/petstore-with-fake-endpoints-models-for-testing.yaml#L1048 with more test cases.

[wing328]

As discussed, let's add test cases in a separate PR as we would like to include this PR in the upcoming v5.2.1 release this weekend.

[agilob]

Opened PR #10154