texdoclib-view.tlu:24: attempt to index a nil value (local 'docfile')

[muzimuzhi]

Reproduction steps:

1. Run texdoc <unknown-name>
2. Answer 1 to the prompt Would you like to search online? (y/N)

$ texdoc blahblah
Unfortunately, there are no good matches for "blahblah".

There may be online documentation available for "blahblah" at
    https://texdoc.org/serve/blahblah/0
This documentation may be for a different version than you have installed.

Would you like to search online? (y/N) 1
...e/2025basic/texmf-dist/scripts/texdoc/texdoclib-view.tlu:24: attempt to index a nil value (local 'docfile')

Google told me that Andreas Eder encountered the same Lua error in May 2024, but it seems that didn't get reported to texdoc. Also noted the steps to trigger the error changed. http://ftp.tug.org/pipermail/tex-live/2024-May/050587.html

texdoc/script/texdoclib-view.tlu

Lines 21 to 25 in b62d3af

	-- view a document
	-- see texdoclib-search.tlu for the structure of the argument
	local function view_doc(docfile)
	M.view_file(docfile.realpath)
	end

texdoc/script/texdoclib-view.tlu

Lines 298 to 310 in b62d3af

	if docs_installed and doclist[1] then
	write(C.badmatch_prompt)
	else
	write(C.nolocaldocs_prompt)
	end
	local ans = io.read('*line')
	if ans:match('^\r?[yY]') then
	M.view_file(url)
	elseif tonumber(ans) then
	view_doc(doclist[tonumber(ans)])
	end

C.badmatch_prompt and C.nolocaldocs_prompt share the same logic to process ans, but only the former accepts numbers, the latter only accepts [yYnN] (or, treat anything other than [yY] as false).