GNU bug report logs - #32400
Context and unified hunk formats not fully documented - no mention of --show-c-function / --show-function-line effect on headers

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Subject: Context and unified hunk formats not fully documented - no mention of
 --show-c-function / --show-function-line effect on headers
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Severity: normal

The info documentation describes headers of these formats:
Context: https://www.gnu.org/software/diffutils/manual/html_node/Context-Format.html
Unified: https://www.gnu.org/software/diffutils/manual/html_node/Unified-Format.html
It assumes that none of the following options was activated:
--show-c-function:
https://www.gnu.org/software/diffutils/manual/html_node/C-Function-Headings.html
--show-function-line:
https://www.gnu.org/software/diffutils/manual/html_node/Specified-Headings.html
When they are activated, the format of the header of some hunks is not
documented.

For example, a unified format hunk header can be "@@ -5,8 +5,10 @@
defmodule Quicksort do", as shown in the second diff on
https://kennyballou.com/blog/2015/10/art-manually-edit-hunks/

This is confusing, and may cause users to think a patch generated by
diff is broken.