immutable option and readonly arrays about openapi-typescript

[drwpow]

Would love a PR for this! My suggestion is to first write the failing test in test/transform/schema-object/array.test.ts for the expected syntax, then get it to pass (without getting the other tests to fail).

I am unfamiliar with the typescript factory API. I was trying to search for some documentation, is there any documentation of the typescript factory API?

Not really; it’s all pretty much trial-and-error. That’s why the granular unit tests exist for every function; it makes it easier to start small when building the AST. Then work upwards until you’re at the entire schema level. Fortunately, the TS factory API has good types (as one would hope), so it also helps guide you in the right direction if you look at the function signatures (and of course, copy from other parts of the code)