test: hush: Test hush loops

The added tests verifies correct behavior of for, while and until loops.

Signed-off-by: Francis Laniel <francis.laniel@amarulasolutions.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

test/hush/Makefile

@@ -7,3 +7,4 @@ obj-y += cmd_ut_hush.o
 obj-y += if.o
 obj-y += dollar.o
 obj-y += list.o
+obj-y += loop.o

test/hush/loop.c

@@ -0,0 +1,65 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * (C) Copyright 2021
+ * Francis Laniel, Amarula Solutions, francis.laniel@amarulasolutions.com
+ */
+
+#include <common.h>
+#include <command.h>
+#include <env_attr.h>
+#include <test/hush.h>
+#include <test/ut.h>
+
+static int hush_test_for(struct unit_test_state *uts)
+{
+	console_record_reset_enable();
+
+	ut_assertok(run_command("for loop_i in foo bar quux quux; do echo $loop_i; done", 0));
+	ut_assert_nextline("foo");
+	ut_assert_nextline("bar");
+	ut_assert_nextline("quux");
+	ut_assert_nextline("quux");
+	ut_assert_console_end();
+
+	puts("Beware: this test set local variable loop_i and it cannot be unset!");
+
+	return 0;
+}
+HUSH_TEST(hush_test_for, 0);
+
+static int hush_test_while(struct unit_test_state *uts)
+{
+	console_record_reset_enable();
+
+	/* Exit status is that of test, so 1 since test is false to quit the loop. */
+	ut_asserteq(1, run_command("while test -z \"$loop_foo\"; do echo bar; loop_foo=quux; done", 0));
+	ut_assert_nextline("bar");
+	ut_assert_console_end();
+
+	puts("Beware: this test set local variable loop_foo and it cannot be unset!");
+
+	return 0;
+}
+HUSH_TEST(hush_test_while, 0);
+
+static int hush_test_until(struct unit_test_state *uts)
+{
+	console_record_reset_enable();
+	env_set("loop_bar", "bar");
+
+	/*
+	 * WARNING We have to use environment variable because it is not possible
+	 * resetting local variable.
+	 */
+	ut_assertok(run_command("until test -z \"$loop_bar\"; do echo quux; setenv loop_bar; done", 0));
+	ut_assert_nextline("quux");
+	ut_assert_console_end();
+
+	/*
+	 * Loop normally resets foo environment variable, but we reset it here in
+	 * case the test failed.
+	 */
+	env_set("loop_bar", NULL);
+	return 0;
+}
+HUSH_TEST(hush_test_until, 0);