ztest: add tests for failing on zassume

Add a test to make sure that when a zassume fails, we mark the test
as failed and print an "Assumption failed" error for the test

Signed-off-by: Yuval Peress <peress@google.com>

tests/ztest/fail/Kconfig

@@ -22,6 +22,9 @@ config ZTEST_FAIL_TEST_PASS_AFTER
 config ZTEST_FAIL_TEST_PASS_TEARDOWN
 	bool "Add a call to ztest_test_pass() in the teardown phase"
 
+config ZTEST_FAIL_TEST_UNEXPECTED_ASSUME
+	bool "Add a test which fails a zassume() call"
+
 endchoice
 
 config TEST_ERROR_STRING
@@ -32,5 +35,6 @@ config TEST_ERROR_STRING
 	default "ERROR: cannot skip in test 'teardown()', bailing" if ZTEST_FAIL_TEST_ASSUME_TEARDOWN
 	default "ERROR: cannot pass in test 'after()', bailing" if ZTEST_FAIL_TEST_PASS_AFTER
 	default "ERROR: cannot pass in test 'teardown()', bailing" if ZTEST_FAIL_TEST_PASS_TEARDOWN
+	default "Assumption failed at " if ZTEST_FAIL_TEST_UNEXPECTED_ASSUME
 
 source "Kconfig.zephyr"

tests/ztest/fail/core/CMakeLists.txt

@@ -19,6 +19,8 @@ elseif(CONFIG_ZTEST_FAIL_TEST_PASS_AFTER)
   list(APPEND SOURCES src/pass_after.cpp)
 elseif(CONFIG_ZTEST_FAIL_TEST_PASS_TEARDOWN)
   list(APPEND SOURCES src/pass_teardown.cpp)
+elseif(CONFIG_ZTEST_FAIL_TEST_UNEXPECTED_ASSUME)
+  list(APPEND SOURCES src/unexpected_assume.cpp)
 endif()
 
 if(BOARD STREQUAL unit_testing)

tests/ztest/fail/core/src/unexpected_assume.cpp

@@ -0,0 +1,16 @@
+/* Copyright (c) 2022 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/ztest.h>
+
+#include "fail_test.hpp"
+
+void fail_test_after_impl(void) {}
+
+void fail_test_teardown_impl(void) {}
+
+ZTEST(fail, test_unexpected_assume)
+{
+	zassume_true(false, NULL);
+}

tests/ztest/fail/testcase.yaml

@@ -50,3 +50,11 @@ tests:
     platform_allow: native_posix
     extra_configs:
       - CONFIG_ZTEST_FAIL_TEST_PASS_TEARDOWN=y
+  testing.fail.unit.fail_on_bad_assumption:
+    type: unit
+    extra_configs:
+      - CONFIG_ZTEST_FAIL_TEST_UNEXPECTED_ASSUME=y
+  testing.fail.zephyr.fail_on_bad_assumption:
+    platform_allow: native_posix
+    extra_configs:
+      - CONFIG_ZTEST_FAIL_TEST_UNEXPECTED_ASSUME=y