fix cran malformat error

[elena-krismer]

I couldn't reproduce the error, but here’s what I discovered:

In some cases, tryCatchseems to struggle with capturing errors from C-level functions. Additionally, the error from curl::curl_fetch_memory() isn't being handled properly (see the screenshot below). The error message appears similar, but it's not exactly the same.

• I came across a related issue where curl encountered testing problems in specific environments, which may be relevant: Stub response from curl_fetch_memory() jeroen/curl#257.

The error message suggests the url is invalid, so for now, I’ve added an extra validation test to check the URL’s format before proceeding. It seems the issue might stem from some unusual behavior in the interaction between R and C functions, where the original URL possibly "gets lost."

[jpquast]

@elena-krismer It is great that you managed to reproduce a similar error message. That helped me to figure out what was actually going on. I assumed the error came from httr::GET but it actually came from httr::http_error as you can see from your screenshot.
In brief, the function handles errors that arise during requests correctly, but if the error is not a standard response error but actually an error with one of the functions then the httr::http_error function tries to retrieve information from a "URL" that is the error message. So I added some code that handles request errors separately from function errors. This should fix it.

[jpquast]

Everything looks good currently. I will wait until the tests passed and merge it into the developer. Then I bump the version and write the cran_comments.