I think you'll find this is fixed in recent versions of pandoc. It's always helpful if you say which version you're running when reporting an issue, but I infer it's an older version, because with the current version I get breaks in the right places. See:

https://pandoc.org/try/?params=%7B%22text%22%3A%22%25+Test+file+one%5Cn%5Cn%60unbroken+line+of+code%60+and%5Cn%60unbroken+line+of+code%60+and%5Cn%60unbroken+line+of+code%60+and%5Cn%60unbroken+line+of+code%60+and%5Cn%60unbroken+line+of+code%60+and%5Cn%60unbroken+line+of+code%60+and%5Cn%60unbroken+line+of+code%60+and%5Cn%60unbroken+line+of+code%60+and%5Cn%22%2C%22to%22%3A%22html5%22%2C%22from%22%3A%22markdown%22%2C%22standalone%22%3Afalse%2C%22embed-resources%22%3Afalse%2C%22table-of-contents%22%3Afalse%2C%22number-sections%22%3Afalse%2C%22citeproc%22%3Afalse%2C%22html-math-method%22%3A%22plain%22%2C%22wrap%22%3A%22auto%22%2C%22highlight-style%22%3Anull%2C%22files%22%3A%7B%7D%2C%22template%22%3Anull%7D

If you don't want to upgrade, there's a simple solution for you:

--wrap=preserve

This will preserve the line breaks in the source markdown instead of automatically rewrapping.



> On Sep 19, 2022, at 2:21 AM, Ian Allen <ida...-4AaKEnNpRjew5LPnMra/2Q@public.gmane.org> wrote:
>
> This is my input using inline verbatim backticks:
> ~~~~~
> % Test file one
>
> `unbroken line of code` and
> `unbroken line of code` and
> `unbroken line of code` and
> `unbroken line of code` and
> `unbroken line of code` and
> `unbroken line of code` and
> `unbroken line of code` and
> `unbroken line of code` and
> ~~~~~
> Command line: `pandoc -s i.md -o i.html`
>
> In the HTML output, pandoc inserts unhelpful newlines in the middle of the code elements (excerpt from `i.html` output file):
> ~~~~~
> <p><code>unbroken line of code</code> and <code>unbroken line of
> code</code> and <code>unbroken line of code</code> and <code>unbroken
> line of code</code> and <code>unbroken line of code</code> and
> <code>unbroken line of code</code> and <code>unbroken line of
> code</code> and <code>unbroken line of code</code> and</p>
> ~~~~~
> Pandoc uses `code{white-space: pre-wrap;}` to format code, and so my browser [preserves the newlines](https://developer.mozilla.org/en-US/docs/Web/CSS/white-space) that pandoc unhelpfully added:
> ~~~~~
> unbroken line of code and unbroken line of
> code and unbroken line of code and unbroken
> line of code and unbroken line of code and unbroken line of code and unbroken line of
> code and unbroken line of code and
> ~~~~~
> This is not pretty and I can't imagine anyone would want this output with the added newlines placed there randomly by pandoc. I did not add those newlines. (I can't protect the spaces by with backslashes inside a verbatim element; the backslashes are treated literally.)
>
> What I want is pandoc HTML output that does not add extra newlines in the middle of code elements. For example, this would work as HTML output:
> ~~~~~
> <p><code>unbroken line of code</code> and <code>unbroken line of code</code>
> and <code>unbroken line of code</code> and <code>unbroken line of code</code>
> and <code>unbroken line of code</code> and <code>unbroken line of code</code>
> and <code>unbroken line of code</code> and <code>unbroken line of code</code>
> and</p>
> ~~~~~
> Then I would be able to choose between `code{white-space: pre-wrap;}` and `code{white-space: pre;}` to format the code elements:
> ~~~~~
> `this is a standard pandoc verbatim element that wraps on output` but
> `this is one that I can tag and use my own CSS not to wrap`{.mycode}
> ~~~~~
> For the wish list: I wish that there were a clean way to write inline verbatim elements that could distinguish between `pre-wrap` and `pre` without having to tag them all with `{.mycode}`. I have teaching materials full of inline verbatim example shell command lines (such as `ls -l /usr/bin`) and I don't want newlines inserted into the middle of those examples, and I don't want them to wrap on output, either.
>
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