t/lib-t6000: refactor name_from_description() to not depend on Perl

The `name_from_description()` test helper uses Perl to munge a given
description and convert it into a name. Refactor it to instead use a
combination of sed(1) and tr(1) so that we drop PERL_TEST_HELPERS
prerequisites in users of this library.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/lib-t6000.sh

@@ -109,13 +109,12 @@ check_output () {
 # All alphanums translated into -'s which are then compressed and stripped
 # from front and back.
 name_from_description () {
-	perl -pe '
-		s/[^A-Za-z0-9.]/-/g;
-		s/-+/-/g;
-		s/-$//;
-		s/^-//;
-		y/A-Z/a-z/;
-	'
+	sed \
+		-e 's/[^A-Za-z0-9.]/-/g' \
+		-e 's/--*/-/g' \
+		-e 's/-$//' \
+		-e 's/^-//' \
+		-e 'y/A-Z/a-z/'
 }
 
 

t/t6002-rev-list-bisect.sh

@@ -7,12 +7,6 @@ test_description='Tests git rev-list --bisect functionality'
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-t6000.sh # t6xxx specific functions
 
-if ! test_have_prereq PERL_TEST_HELPERS
-then
-	skip_all='skipping rev-list bisect tests; Perl not available'
-	test_done
-fi
-
 # usage: test_bisection max-diff bisect-option head ^prune...
 #
 # e.g. test_bisection 1 --bisect l1 ^l0

t/t6003-rev-list-topo-order.sh

@@ -8,12 +8,6 @@ test_description='Tests git rev-list --topo-order functionality'
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-t6000.sh # t6xxx specific functions
 
-if ! test_have_prereq PERL_TEST_HELPERS
-then
-	skip_all='skipping rev-list topo-order tests; Perl not available'
-	test_done
-fi
-
 list_duplicates()
 {
     "$@" | sort | uniq -d