DOI breaking and hyphenation

Just now I encountered a situation where a DOI, entered with \doi, was cut across lines and a hyphen inserted at the break, turning

10.1016/j.ijheatfluidflow.2008.07.001

into

10.1016/j.ijheatfluid-
flow.2008.07.001

This is because the doi package uses \href from hyperref, which treats its second argument like normal text. Clearly adding a hyphen inside a URL is a bad idea.

The url package works differently, its does not add hyphens and instead defines possible break points. Heiko Oberdiek pointed out that the best of both worlds is obtained with \nolinkurl, to format (if I understood correctly) the second argument of \href using \url.

The attached example (to be typeset with LuaLaTeX for the above hyphenation to occur) compares the outputs of

\doi{<doi>}
\href{https://doi.org/<doi>}{https://doi.org/<doi>}
\url{https://doi.org/<doi>}
\href{https://doi.org/<doi>}{\nolinkurl{https://doi.org/<doi>}}
\href{https://doi.org/<doi>}{\nolinkurl{doi:<doi>}}

The last of these gives the same output as \doi, without the unwanted hyphen. The only difference is doi:, outside the link with \doi and inside it with \href+\nolinkurl (I prefer the latter).

The whole doi package was introduced to deal with DOIs containing non-sensical characters like

10.1175/1520-0469(1983)040<0396:SWALW>2.0.CO;2

At the time, \href couldn't deal with these characters. Now it seems it can, see the second example in the attached file.

Hence the two questions:

• Is the doi package still necessary? Could its functionality be implemented simply with \href{https://doi.org/<doi>}{\nolinkurl{doi:<doi>}}?
• Assuming it is still necessary, could the clever breakpoint handling brought by the url package be combined into it?

doi-hyphen-example.zip

Start with the doi package behavior shown in doi-hyphen-example.zip and typeset the comparison with LuaLaTeX. Compare \doi with the \href, \url, and \nolinkurl examples using both DOI values from the issue. Done means DOI links retain valid line-breaking behavior without inserting a hyphen, including the DOI containing special characters.