[BUG] [Go-server] invalid composite literal type string

[vingarzan]

The patch does an alternative initialization of a Go-lang variable, such that a custom pre-check and multiple alternative := initialization would be needed in the mustache template. This fixes #17373 which would generate invalid code like:

  nameParam := string{} // error: "invalid composite literal type string"

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.
• Run the following to build the project and update samples:

  ./mvnw clean package || exit
  ./bin/generate-samples.sh ./bin/configs/*.yaml || exit
  ./bin/utils/export_docs_generators.sh || exit
  

  (For Windows users, please run the script in Git BASH)
  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.
  These must match the expectations made by your contribution.
  You may regenerate an individual generator by passing the relevant config(s) as an argument to the script, for example ./bin/generate-samples.sh bin/configs/java*.
  IMPORTANT: Do NOT purge/delete any folders/files (e.g. tests) when regenerating the samples as manually written tests may be removed.
• File the PR against the correct branch: master (upcoming 7.x.0 minor release - breaking changes with fallbacks), 8.0.x (breaking changes without fallbacks)
• If your PR is targeting a particular programming language, @mention the technical committee members, so they are more likely to review the pull request.

@antihax @grokify @kemokemo @jirikuncar @ph4r5h4d @lwj5

[wing328]

thanks for the PR.

what about adding a test or 2 to the test spec (modules/openapi-generator/src/test/resources/3_0/go-server/petstore.yaml) and regenerate the samples so that the issue is covered moving forward?

[vingarzan]

TBH, I'm super new to this project and quite rusty in Java, so I have no clue where/what to add. Maybe if we'd add to the PetStore example some data structure which would trigger this?

[wing328]

i added some tests via #20474

and tested your change locally to confirm the fix.

thanks for the PR.

will merge #20474 after merging your fix.