Feature/zephyr ztest (#118)

* Leverage (older) embedded unit tests into external unit tests build upon copy of Zephyr's ztest library and CMake.

* Expand top-level CMake build to run external unit tests.

* Expand Zephyr module extension to run external unit tests via west or sanitycheck.

Co-authored-by: Gregory Shue <gregory.shue@legrand.us>

test/ztest/include/ztest_mock.h

@@ -0,0 +1,119 @@
+/*
+ * Copyright (c) 2016 Intel Corporation
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/**
+ * @file
+ *
+ * @brief Ztest mocking support
+ */
+
+#ifndef __ZTEST_MOCK_H__
+#define __ZTEST_MOCK_H__
+
+/**
+ * @defgroup ztest_mock Ztest mocking support
+ * @ingroup ztest
+ *
+ * This module provides simple mocking functions for unit testing. These
+ * need CONFIG_ZTEST_MOCKING=y.
+ *
+ * @{
+ */
+
+/**
+ * @brief Tell function @a func to expect the value @a value for @a param
+ *
+ * When using ztest_check_expected_value(), tell that the value of @a param
+ * should be @a value. The value will internally be stored as an `uintptr_t`.
+ *
+ * @param func Function in question
+ * @param param Parameter for which the value should be set
+ * @param value Value for @a param
+ */
+#define ztest_expect_value(func, param, value) \
+	z_ztest_expect_value(STRINGIFY(func), STRINGIFY(param), \
+			    (uintptr_t)(value))
+
+/**
+ * @brief If @a param doesn't match the value set by ztest_expect_value(),
+ * fail the test
+ *
+ * This will first check that does @a param have a value to be expected, and
+ * then checks whether the value of the parameter is equal to the expected
+ * value. If either of these checks fail, the current test will fail. This
+ * must be called from the called function.
+ *
+ * @param param Parameter to check
+ */
+#define ztest_check_expected_value(param) \
+	z_ztest_check_expected_value(__func__, STRINGIFY(param), \
+				    (uintptr_t)(param))
+
+/**
+ * @brief Tell @a func that it should return @a value
+ *
+ * @param func Function that should return @a value
+ * @param value Value to return from @a func
+ */
+#define ztest_returns_value(func, value) \
+	z_ztest_returns_value(STRINGIFY(func), (uintptr_t)(value))
+
+/**
+ * @brief Get the return value for current function
+ *
+ * The return value must have been set previously with ztest_returns_value().
+ * If no return value exists, the current test will fail.
+ *
+ * @returns The value the current function should return
+ */
+#define ztest_get_return_value() \
+	z_ztest_get_return_value(__func__)
+
+/**
+ * @brief Get the return value as a pointer for current function
+ *
+ * The return value must have been set previously with ztest_returns_value().
+ * If no return value exists, the current test will fail.
+ *
+ * @returns The value the current function should return as a `void *`
+ */
+#define ztest_get_return_value_ptr() \
+	((void *)z_ztest_get_return_value(__func__))
+
+/**
+ * @}
+ */
+
+#ifdef CONFIG_ZTEST_MOCKING
+
+#include <zephyr/types.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+void z_init_mock(void);
+int z_cleanup_mock(void);
+
+void z_ztest_expect_value(const char *fn, const char *name, uintptr_t value);
+void z_ztest_check_expected_value(const char *fn, const char *param,
+				 uintptr_t value);
+
+void z_ztest_returns_value(const char *fn, uintptr_t value);
+uintptr_t z_ztest_get_return_value(const char *fn);
+
+#ifdef __cplusplus
+}
+#endif
+
+#else /* !CONFIG_ZTEST_MOCKING */
+
+#define z_init_mock()
+#define z_cleanup_mock() 0
+
+#endif  /* CONFIG_ZTEST_MOCKING */
+
+#endif  /* __ZTEST_H__ */