Merge branch 'jk/tests-write-script'

* jk/tests-write-script:
  t0300: use write_script helper
  tests: add write_script helper function

t/t0300-credentials.sh

@@ -14,22 +14,18 @@ test_expect_success 'setup helper scripts' '
 	done
 	EOF
 
-	cat >git-credential-useless <<-\EOF &&
-	#!/bin/sh
+	write_script git-credential-useless <<-\EOF &&
 	. ./dump
 	exit 0
 	EOF
-	chmod +x git-credential-useless &&
 
-	cat >git-credential-verbatim <<-\EOF &&
-	#!/bin/sh
+	write_script git-credential-verbatim <<-\EOF &&
 	user=$1; shift
 	pass=$1; shift
 	. ./dump
 	test -z "$user" || echo username=$user
 	test -z "$pass" || echo password=$pass
 	EOF
-	chmod +x git-credential-verbatim &&
 
 	PATH="$PWD:$PATH"
 '

t/test-lib.sh

@@ -395,11 +395,20 @@ test_config () {
 	git config "$@"
 }
 
+
 test_config_global () {
 	test_when_finished "test_unconfig --global '$1'" &&
 	git config --global "$@"
 }
 
+write_script () {
+	{
+		echo "#!${2-"$SHELL_PATH"}" &&
+		cat
+	} >"$1" &&
+	chmod +x "$1"
+}
+
 # Use test_set_prereq to tell that a particular prerequisite is available.
 # The prerequisite can later be checked for in two ways:
 #