Revert "doc: Emacs Packages: Remove outdated commentary on testing."

This reverts commit b17268b53e9fb1b1ac2ad29fe7633b52744fee2f, which was
meant for the ‘emacs-team’ branch as part of a patch series.

Change-Id: I9d9b01924698aaf5bb6ac2c8472311976eeaacc6

1 files changed, 8 insertions, 1 deletions

diff --git a/doc/contributing.texi b/doc/contributing.texi
index eb105fc6fbd..ab4f30d54b5 100644
--- a/doc/contributing.texi
+++ b/doc/contributing.texi
@@ -1433,7 +1433,14 @@ called at the top level.
 Emacs packages should preferably use the Emacs build system
 (@pxref{emacs-build-system}), for uniformity and the benefits provided
 by its build phases, such as the auto-generation of the autoloads file
-and the byte compilation of the sources.
+and the byte compilation of the sources.  Because there is no
+standardized way to run a test suite for Emacs packages, tests are
+disabled by default.  When a test suite is available, it should be
+enabled by setting the @code{#:tests?} argument to @code{#true}.  By
+default, the command to run the test is @command{make check}, but any
+command can be specified via the @code{#:test-command} argument.  The
+@code{#:test-command} argument expects a list containing a command and
+its arguments, to be invoked during the @code{check} phase.
 
 The Elisp dependencies of Emacs packages are typically provided as
 @code{propagated-inputs} when required at run time.  As for other