Add support for regress tests using testsudoers

plugins/sudoers/regress/testsudoers/test1.ok

@@ -0,0 +1,8 @@
+Parses OK.
+
+Entries for user root:
+
+ALL = ALL
+	host  matched
+
+Command unmatched

plugins/sudoers/regress/testsudoers/test1.sh

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+#!/bin/sh
+#
+# Test for NULL dereference with "sudo -g group" when the sudoers rule
+# has no runas user or group listed.
+# This is RedHat bug Bug 667103.
+#
+
+WANT=${SRCDIR-.}/regress/testsudoers/test1.ok
+GOT=test1.out
+./testsudoers -g wheel root id > $GOT <<EOF
+root ALL = ALL
+EOF
+
+# Check results
+if cmp $WANT $GOT >/dev/null; then
+    echo "testsudoers 1: OK"
+else
+    echo "testsudoers 1: FAILED"
+    diff $WANT $GOT
+fi