bug: asciidoc export: literal "]" interrupts footnote.

[Will47]

If a footnote text includes right brackets - ] - the first one will match with the "footnote:[" markup of asciidoc, provoking an early interruption of the footnote, and pushing back the end of the footnote text in the main text.

Example, using test.docx, and running:
pandoc -f docx -t asciidoc test.docx
produces the following output:
textfootnote:[[…] footnote]

Escaping the inner right brackets should fix the issue (cf. asciidoctor/asciidoctor#2495 (comment)), producing this output instead:
textfootnote:[[…\] footnote]

I used Pandoc v2.5 for the test, but it should still apply to the latest version from my understanding of the AsciiDoc writer code.

[jgm]

The big question is whether we can get away with just always escaping literal bracket characters.

[Will47]

Escaping ] is only required inside macros, cf. https://asciidoc.org/userguide.html#_macros:

• <attrlist> is a list of attributes enclosed in square brackets.
• ] characters inside attribute lists must be escaped with a backslash.

Outside of macros, ] has no particular meaning and \] will be rendered as \]. So if that's what you mean by always, I'm afraid you won't get away with that.

AsciiDoctor seems a bit more generic but aligned nevertheless on AsciiDoc on this particular issue, cf. https://asciidoctor.org/docs/user-manual/#attribute-list-substitutions:

If the attribute value contains the same quote character being used to enclose the value, escape the quote character in the value by prefixing it with a backslash (e.g., title="\"Dark Horse\" is a song by George Harrison").