maint: add new syntax-check rule to prohibit use of skip_

* cfg.mk (sc_prohibit_skip_): New rule.
* tests/init.cfg (skip_test_): Add a comment.

2 files changed, 9 insertions, 0 deletions

diff --git a/cfg.mk b/cfg.mk
index 9869ebab8..15cf98c16 100644
--- a/cfg.mk
+++ b/cfg.mk
@@ -221,6 +221,12 @@ sc_prohibit_emacs__indent_tabs_mode__setting:
 	halt='use of emacs indent-tabs-mode: setting'			\
 	  $(_sc_search_regexp)
 
+# Use skip_test_ rather than init.sh's "skip_" function.
+sc_prohibit_skip_:
+	@prohibit=' skip[_] '						\
+	halt="use init.cfg's skip_test_, not init.sh's skip_"		\
+	  $(_sc_search_regexp)
+
 # Ensure that each file that contains fail=1 also contains fail=0.
 # Otherwise, setting file=1 in the environment would make tests fail
 # unexpectedly.
diff --git a/tests/init.cfg b/tests/init.cfg
index 55d757175..3a59bbd6b 100644
--- a/tests/init.cfg
+++ b/tests/init.cfg
@@ -34,6 +34,9 @@ sanitize_path_()
   export PATH
 }
 
+# Use this function rather than init.sh's skip_.
+# The "skip_" function emits its diagnostic only to one stream.
+# This one emits it both to the tty and to the log file.
 skip_test_()
 {
   echo "$0: skipping test: $@" | head -1 1>&9