[swift6] Change JSONEncodable protocol to always return String

[x-sheep]

By no longer using Any as a type, we can assert that all parameter dictionaries are Sendable. This allows upgrading Alamofire to the latest version.

Fixes #20398

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[x-sheep]

I don't know why the test is failing. It seems the test output itself is broken?

/Users/vagrant/.asdf/installs/ruby/3.3.7/lib/ruby/gems/3.3.0/gems/xcpretty-0.4.0/lib/xcpretty/parser.rb:366:in `parse': uninitialized constant XCPretty::Parser::ERB (NameError)

        formatter.format_failing_test($2, $3, ERB::Util.html_escape($4), $1)
                                              ^^^
	from /Users/vagrant/.asdf/installs/ruby/3.3.7/lib/ruby/gems/3.3.0/gems/xcpretty-0.4.0/lib/xcpretty/formatters/formatter.rb:88:in `pretty_format'

[4brunu]

Hi @x-sheep, thanks for creating this PR, this is a nice contribution.

By building this locally I got the following errors:

/Users/OpenAPI/Developer/Github/openapi-generator/samples/client/petstore/swift6/asyncAwaitLibrary/Sources/PetstoreClient/Infrastructure/URLSessionImplementations.swift:707:1: error: instance method 'encode(request:with:)' has different argument labels from those required by protocol 'ParameterEncoding' ('encode(_:with:)')
432 | 
433 | public protocol ParameterEncoding {
434 |     func encode(_ urlRequest: URLRequest, with parameters: [String: any Sendable]?) throws -> URLRequest
    |          `- note: requirement 'encode(_:with:)' declared here
435 | }
436 | 
    :
705 | }
706 | 
707 | extension JSONDataEncoding: ParameterEncoding {}
    | `- error: instance method 'encode(request:with:)' has different argument labels from those required by protocol 'ParameterEncoding' ('encode(_:with:)')
708 | 
709 | public enum OpenAPIInterceptorRetry {

/Users/OpenAPI/Developer/Github/openapi-generator/samples/client/petstore/swift6/asyncAwaitLibrary/Sources/PetstoreClient/Infrastructure/JSONDataEncoding.swift:30:17: note: 'encode(request:with:)' declared here
28 |     ///
29 |     /// - returns: The encoded request.
30 |     public func encode(request: URLRequest, with parameters: [String: any Sendable]?) -> URLRequest {
   |                 `- note: 'encode(request:with:)' declared here
31 |         var urlRequest = request
32 | 
/Users/OpenAPI/Developer/Github/openapi-generator/samples/client/petstore/swift6/asyncAwaitLibrary/Sources/PetstoreClient/Infrastructure/URLSessionImplementations.swift:707:1: error: instance method 'encode(request:with:)' has different argument labels from those required by protocol 'ParameterEncoding' ('encode(_:with:)')
432 | 
433 | public protocol ParameterEncoding {
434 |     func encode(_ urlRequest: URLRequest, with parameters: [String: any Sendable]?) throws -> URLRequest
    |          `- note: requirement 'encode(_:with:)' declared here
435 | }
436 | 
    :
705 | }
706 | 
707 | extension JSONDataEncoding: ParameterEncoding {}
    | `- error: instance method 'encode(request:with:)' has different argument labels from those required by protocol 'ParameterEncoding' ('encode(_:with:)')
708 | 
709 | public enum OpenAPIInterceptorRetry {

/Users/OpenAPI/Developer/Github/openapi-generator/samples/client/petstore/swift6/asyncAwaitLibrary/Sources/PetstoreClient/Infrastructure/JSONDataEncoding.swift:30:17: note: 'encode(request:with:)' declared here
28 |     ///
29 |     /// - returns: The encoded request.
30 |     public func encode(request: URLRequest, with parameters: [String: any Sendable]?) -> URLRequest {
   |                 `- note: 'encode(request:with:)' declared here
31 |         var urlRequest = request
32 | 
[3/3] Compiling PetstoreClient URLSessionImplementations.swift

[4brunu]

Since we are having some problems with the server returning some errors, you can try to build the sample projects locally by commenting the following lines (please don't commit this change).

openapi-generator/samples/client/petstore/swift6/swift6_test_all.sh

Lines 6 to 15 in 1eb8c58

	# example project with unit tests
	(cd $DIRECTORY/alamofireLibrary/SwaggerClientTests/ && ./run_xcodebuild.sh)
	(cd $DIRECTORY/apiNonStaticMethod/SwaggerClientTests/ && ./run_xcodebuild.sh)
	(cd $DIRECTORY/asyncAwaitLibrary/SwaggerClientTests/ && ./run_xcodebuild.sh)
	# (cd $DIRECTORY/combineLibrary/SwaggerClientTests/ && ./run_xcodebuild.sh)
	(cd $DIRECTORY/combineDeferredLibrary/SwaggerClientTests/ && ./run_xcodebuild.sh)
	(cd $DIRECTORY/default/SwaggerClientTests/ && ./run_xcodebuild.sh)
	# (cd $DIRECTORY/promisekitLibrary/SwaggerClientTests/ && ./run_xcodebuild.sh)
	(cd $DIRECTORY/rxswiftLibrary/SwaggerClientTests/ && ./run_xcodebuild.sh)
	(cd $DIRECTORY/urlsessionLibrary/SwaggerClientTests/ && ./run_xcodebuild.sh)

And then you can run the following command in the terminal to build all the swift sample projects.
sh swift6_test_all.sh

[4brunu]

Now it builds locally.
Looks good to me 👍
Thanks for this awesome contribution.
We are open to contributions.
Do you see other areas where the Swift 6 generator needs improvement?

[wing328]

@x-sheep thanks for the PR

when you've time, can you please PM me via Slack for a quick chat?

https://join.slack.com/t/openapi-generator/shared_invite/zt-2wmkn4s8g-n19PJ99Y6Vei74WMUIehQA