[csharp] Use the provided 'sourceFolder' property to generate the test folder

[Starkie]

Hi all!

This issue is regarding the csharp-netcore generator. There is a bit of an inconsistency in how the test folders are generated when the sourceFolder property is provided. For example:

• Set the option sourceFolder to anything other than src.
  • In this case, I left it empty: --additional-properties=sourceFolder=""
• Generate the client
• See that the client was generated in the provided sourceFolder... but the tests where generated in src:
  

In the AbstractCSharpCodegen.java, there is a TODO a few years old saying that a separate option for testFolder could be added:

openapi-generator/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractCSharpCodegen.java

Lines 73 to 75 in 8551b0a

	// TODO: Add option for test folder output location. Nice to allow e.g. ./test instead of ./src.
	// This would require updating relative paths (e.g. path to main project file in test project file)
	protected String testFolder = sourceFolder;

Until that is implemented, I created a little workaround, assigning the provided sourceFolder parameter to the testFolder.

With this change, the projects are generated as expected:

Related issue: #1390

PR checklist

• Read the contribution guidelines.
• Pull Request title clearly describes the work in the pull request and Pull Request description provides details about how to validate the work. Missing information here may result in delayed response from the community.
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  ./mvnw clean package 
  ./bin/generate-samples.sh
  ./bin/utils/export_docs_generators.sh
  

  Commit all changed files.
  This is important, as CI jobs will verify all generator outputs of your HEAD commit as it would merge with master.
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  • @mandrean @frankyjuang @shibayan @Blackclaws @lucamazzanti

[Starkie]

I executed the given commands and there were no changes.

./mvnw clean package 
./bin/generate-samples.sh
./bin/utils/export_docs_generators.sh

[Blackclaws]

While I'll say that this doesn't really affect much and could be merged as is, I'd still also vote for just "doing it right" in the first place. Ergo implementing a testFolder additionalProperty and using that to set the location.

[wing328]

Let's go with this and later consider the testFolder option/additional-properties when there's a demand for it.