diff --git a/test/sharness/t0018-indent.sh b/test/sharness/t0018-indent.sh
new file mode 100755
index 000000000..6ba37d045
--- /dev/null
+++ b/test/sharness/t0018-indent.sh
@@ -0,0 +1,13 @@
+#!/bin/sh
+
+test_description="Test sharness test indent"
+
+. lib/test-lib.sh
+
+for file in $(find .. -name 't*.sh' -type f); do
+	test_expect_success "indent in $file is not using spaces" '
+		test_must_fail grep -P "^\\t* " $file
+	'
+done
+
+test_done