[Dart2]: improved error reporting

[ircecho]

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@ircecho (2017/07) @swipesight (2018/09)

Description of the PR

(details of the change, additional tests that have been done, reference to the issue for tracking, etc)

Fixed catch in ApiClient to properly display exceptions and errors.

Original error is gobbled, overshadowed by exception in catch block.

Unhandled exception:
type '_TypeError' is not a subtype of type 'Exception'
#0      ApiClient._deserialize (file:///.../lib/api_client.dart:226:78)
#1      ApiClient.deserialize (file:///.../lib/api_client.dart:238:12)
...

becomes

type '_InternalLinkedHashMap<String, dynamic>' is not a subtype of type 'Map<String, Map<String, dynamic>>'
#0      new ArticleRepresentation.fromJson (file:///.../lib/model/article_representation.dart:85:59)
#1      ArticleRepresentation.listFromJson.<anonymous closure> (file:///.../lib/model/article_representation.dart:128:87)
...

Original error is visible properly.

[wing328]

Thanks for the PR but your commit (as shown in the Commits tab) is not linked to your Github account, which means this PR won't count as your contribution in https://github.com/OpenAPITools/openapi-generator/graphs/contributors.

Let me know if you need help fixing it.

Ref: https://github.com/OpenAPITools/openapi-generator/wiki/FAQ#how-can-i-update-commits-that-are-not-linked-to-my-github-account

[ircecho]

@wing328 Fixed.

[wing328]

@ircecho looks good now.

May I know if you've dartfmt installed locally in your machine? If yes, can you run the following to setup an environment variable:

export DART_FMT_PATH=/usr/local/bin/dart

and then update the samples again so that the Dart code will have better format.

(This is a new feature we added recently. Please let us know if you've any feedback)

[ircecho]

@wing328 Fixed.

My only suggestion to this feature would be to use dartfmt automatically, if it is available in the path. I thought that was the case which is why I did not bother to check. Anyways, now the formatting should be fine.

[wing328]

@ircecho thanks for the suggestion. Later we may update the logic to search for dartfmt in the path (Windows, Mac, Linux) and use it automatically if found.

[ghost]

Nice catch!