Bump jmustache 1.15 -> 1.16

[bachorp]

Superseeds #19575, resolves #20375.

I applied the following logic to adjust our templates to jmustache's changed semantics.

import re
from pathlib import Path

for file in filter(
    lambda p: p.is_file()
    and not p.name.endswith(".jar.mustache")
    and not p.name.endswith(".war.mustache"),
    Path("modules/openapi-generator/src/main/resources").glob("**/*.mustache"),
):
    # I don't know how jmustache behaves with trailing whitespace, but this does not occur.
    assert not re.match(r"^ *\{\{>[^\}]+\}\} +$",
                        file.read_text(), flags=re.MULTILINE)
    file.write_text(
        # add comment to avoid standalone mode
        re.sub(
            r"^ +\{\{>[^\}]+\}\}$",
            lambda m: m.group(0) + "{{! prevent indent}}",
            # add newline to non-indented standalones (except at start of file)
            re.sub(
                r"^\{\{>[^\}]+\}\}\n",
                lambda m: m.group(0) if m.start(0) == 0 else m.group(0) + "\n",
                file.read_text(),
                flags=re.MULTILINE,
            ),
            flags=re.MULTILINE,
        )
    )

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 WSL)
  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.

[wing328]

@bachorp thanks for the pr

can you please pm me via Slack when you've time to discuss this?

[bachorp]

@wing328 Sure. Please send me an invite. The link on the website is expired.

[wing328]

can you try https://join.slack.com/t/openapi-generator/shared_invite/zt-38mcfd9x2-DuLqQ_x1BPnjRSSShrcmPA ?

[wing328]

thanks for your awesome work

lgtm after reviewing the change locally

let's give it a try

[Mattias-Sehlstedt]

@wing328 Is it intentional that this PR will make annotations float one step above the class definition?

To me it looks really odd, but since it has been applied in a lot of places I am wondering if it actually is intentional?

Edit: Was due to having the old jmustache version

[bachorp]

No. The changes to the templates are expected to cancel out with the bump of jmustache. If templates have been written against the old version of jmustache, they might need to be updated (which is why there was still a change of the output).