test: unit test uart_printf.c

Add unit tests to get uart_printf.c to 100% coverage.

BRANCH=none
BUG=none
TEST=twister

Signed-off-by: Yuval Peress <peress@google.com>
Change-Id: I2fdbea71a7048a2187c599052bf7180a97ee3ad2
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/4004509
Reviewed-by: Abe Levkoy <alevkoy@chromium.org>
Code-Coverage: Zoss <zoss-cl-coverage@prod.google.com>

10 files changed, 253 insertions, 4 deletions

diff --git a/common/uart_printf.c b/common/uart_printf.c
index 01fd1353d2..a4fecf5c73 100644
--- a/common/uart_printf.c
+++ b/common/uart_printf.c
@@ -31,9 +31,10 @@ int uart_putc(int c)
 int uart_puts(const char *outstr)
 {
 	/* Put all characters in the output buffer */
-	while (*outstr) {
-		if (__tx_char(NULL, *outstr++) != 0)
+	for (; *outstr != '\0'; ++outstr) {
+		if (__tx_char(NULL, *outstr) != 0) {
 			break;
+		}
 	}
 
 	uart_tx_start();
@@ -48,8 +49,9 @@ int uart_put(const char *out, int len)
 
 	/* Put all characters in the output buffer */
 	for (written = 0; written < len; written++) {
-		if (__tx_char(NULL, *out++) != 0)
+		if (__tx_char(NULL, *out++) != 0) {
 			break;
+		}
 	}
 
 	uart_tx_start();
@@ -63,8 +65,9 @@ int uart_put_raw(const char *out, int len)
 
 	/* Put all characters in the output buffer */
 	for (written = 0; written < len; written++) {
-		if (uart_tx_char_raw(NULL, *out++) != 0)
+		if (uart_tx_char_raw(NULL, *out++) != 0) {
 			break;
+		}
 	}
 
 	uart_tx_start();
diff --git a/util/twister_tags.py b/util/twister_tags.py
index 692fdc1e99..68ac5846bd 100755
--- a/util/twister_tags.py
+++ b/util/twister_tags.py
@@ -29,6 +29,7 @@ TAG_TO_DESCRIPTION = {
     "mkbp": "Testing the MKBP (Matrix Keyboard Protocol) stack",
     "system": "Directly test functions in common/system.c or shim/src/system.c",
     "spi": "SPI related tests",
+    "uart": "UART related tests",
 }
 
 SCRIPT_PATH = os.path.realpath(__file__)
diff --git a/zephyr/test/uart_printf/CMakeLists.txt b/zephyr/test/uart_printf/CMakeLists.txt
new file mode 100644
index 0000000000..78e0791652
--- /dev/null
+++ b/zephyr/test/uart_printf/CMakeLists.txt
@@ -0,0 +1,29 @@
+# Copyright 2022 The ChromiumOS Authors
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+cmake_minimum_required(VERSION 3.20.0)
+set(CMAKE_CXX_STANDARD 20)
+
+project(uart_printf)
+
+set(SOURCES
+    ../../../common/uart_printf.c
+    src/fakes.cc
+    src/main.cc
+)
+
+# Create the unittest libraries and binary
+find_package(Zephyr COMPONENTS unittest REQUIRED HINTS $ENV{ZEPHYR_BASE})
+
+target_sources(testbinary
+  PRIVATE
+    ../../../common/uart_printf.c
+    src/fakes.cc
+    src/main.cc
+)
+
+target_include_directories(testbinary
+  PRIVATE
+    include
+)
diff --git a/zephyr/test/uart_printf/include/common.h b/zephyr/test/uart_printf/include/common.h
new file mode 100644
index 0000000000..79af9594b3
--- /dev/null
+++ b/zephyr/test/uart_printf/include/common.h
@@ -0,0 +1,12 @@
+/* Copyright 2022 The ChromiumOS Authors
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef ZEPHYR_TEST_UART_PRINTF_INCLUDE_COMMON_H_
+#define ZEPHYR_TEST_UART_PRINTF_INCLUDE_COMMON_H_
+
+#define EC_SUCCESS 0
+#define EC_ERROR_OVERFLOW -1
+
+#endif /* ZEPHYR_TEST_UART_PRINTF_INCLUDE_COMMON_H_ */
diff --git a/zephyr/test/uart_printf/include/printf.h b/zephyr/test/uart_printf/include/printf.h
new file mode 100644
index 0000000000..b6fcf6337d
--- /dev/null
+++ b/zephyr/test/uart_printf/include/printf.h
@@ -0,0 +1,23 @@
+/* Copyright 2022 The ChromiumOS Authors
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef ZEPHYR_TEST_UART_PRINTF_INCLUDE_PRINTF_H_
+#define ZEPHYR_TEST_UART_PRINTF_INCLUDE_PRINTF_H_
+
+#include <zephyr/fff.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef int (*vfnprintf_addchar_t)(void *, int);
+DECLARE_FAKE_VALUE_FUNC(int, vfnprintf, vfnprintf_addchar_t, void *,
+			const char *, va_list);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* ZEPHYR_TEST_UART_PRINTF_INCLUDE_PRINTF_H_ */
diff --git a/zephyr/test/uart_printf/include/uart.h b/zephyr/test/uart_printf/include/uart.h
new file mode 100644
index 0000000000..51fd42a17e
--- /dev/null
+++ b/zephyr/test/uart_printf/include/uart.h
@@ -0,0 +1,28 @@
+/* Copyright 2022 The ChromiumOS Authors
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef ZEPHYR_TEST_UART_PRINTF_INCLUDE_UART_H_
+#define ZEPHYR_TEST_UART_PRINTF_INCLUDE_UART_H_
+
+#include <zephyr/fff.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+int uart_putc(int c);
+int uart_puts(const char *outstr);
+int uart_put(const char *out, int len);
+int uart_put_raw(const char *out, int len);
+int uart_printf(const char *format, ...);
+
+DECLARE_FAKE_VALUE_FUNC(int, uart_tx_char_raw, void *, int);
+DECLARE_FAKE_VOID_FUNC(uart_tx_start);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* ZEPHYR_TEST_UART_PRINTF_INCLUDE_UART_H_ */
diff --git a/zephyr/test/uart_printf/prj.conf b/zephyr/test/uart_printf/prj.conf
new file mode 100644
index 0000000000..6ec8f4d2a9
--- /dev/null
+++ b/zephyr/test/uart_printf/prj.conf
@@ -0,0 +1,6 @@
+# Copyright 2022 The ChromiumOS Authors
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+CONFIG_ZTEST=y
+CONFIG_ZTEST_NEW_API=y
diff --git a/zephyr/test/uart_printf/src/fakes.cc b/zephyr/test/uart_printf/src/fakes.cc
new file mode 100644
index 0000000000..0bb5fea1eb
--- /dev/null
+++ b/zephyr/test/uart_printf/src/fakes.cc
@@ -0,0 +1,36 @@
+/* Copyright 2022 The ChromiumOS Authors
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include <zephyr/fff.h>
+#include <zephyr/ztest.h>
+
+#include "printf.h"
+#include "uart.h"
+
+DEFINE_FFF_GLOBALS;
+
+/* printf.h */
+DEFINE_FAKE_VALUE_FUNC(int, vfnprintf, vfnprintf_addchar_t, void *,
+		       const char *, va_list);
+
+/* uart.h */
+DEFINE_FAKE_VALUE_FUNC(int, uart_tx_char_raw, void *, int);
+DEFINE_FAKE_VOID_FUNC(uart_tx_start);
+
+static void fake_reset_rule_before(const struct ztest_unit_test *test,
+				   void *data)
+{
+	ARG_UNUSED(test);
+	ARG_UNUSED(data);
+
+	/* printf.h */
+	RESET_FAKE(vfnprintf);
+
+	/* uart.h */
+	RESET_FAKE(uart_tx_char_raw);
+	RESET_FAKE(uart_tx_start);
+}
+
+ZTEST_RULE(fake_reset, fake_reset_rule_before, nullptr);
diff --git a/zephyr/test/uart_printf/src/main.cc b/zephyr/test/uart_printf/src/main.cc
new file mode 100644
index 0000000000..e84c5c76ba
--- /dev/null
+++ b/zephyr/test/uart_printf/src/main.cc
@@ -0,0 +1,103 @@
+/* Copyright 2022 The ChromiumOS Authors
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include <cstring>
+#include <ranges>
+#include <string>
+
+#include <zephyr/ztest.h>
+
+#include "common.h"
+#include "printf.h"
+#include "uart.h"
+
+ZTEST_SUITE(uart_printf, nullptr, nullptr, nullptr, nullptr, nullptr);
+
+ZTEST(uart_printf, test_uart_putc)
+{
+	int return_vals[] = { 0, -1 };
+
+	SET_RETURN_SEQ(uart_tx_char_raw, return_vals, 2);
+
+	zassert_ok(uart_putc(5));
+	zassert_equal(EC_ERROR_OVERFLOW, uart_putc(5));
+}
+
+ZTEST(uart_printf, test_uart_put_success)
+{
+	const std::string test_string = "test string";
+	std::string output_string;
+
+	/* Print the whole string */
+	zassert_equal(test_string.size(),
+		      static_cast<size_t>(uart_put(test_string.c_str(),
+						   test_string.size())));
+	zassert_equal(test_string.size(), uart_tx_char_raw_fake.call_count);
+
+	/* Copy the history so it's easier to assert */
+	for (auto i :
+	     std::views::iota(static_cast<size_t>(0), test_string.size())) {
+		output_string += uart_tx_char_raw_fake.arg1_history[i];
+	}
+
+	/* Verify that the string was passed to uart_tx_char_raw() */
+	zassert_equal(test_string, output_string);
+}
+
+ZTEST(uart_printf, test_uart_put_fail_tx)
+{
+	const char test_string[] = "\n";
+
+	uart_tx_char_raw_fake.return_val = -1;
+
+	/* Try printing the newline */
+	zassert_equal(0, uart_put(test_string, 1));
+	zassert_equal(1, uart_tx_char_raw_fake.call_count);
+	zassert_equal('\r', uart_tx_char_raw_fake.arg1_val);
+}
+
+ZTEST(uart_printf, test_uart_puts_fail_tx)
+{
+	const char test_string[] = "\n\0";
+
+	uart_tx_char_raw_fake.return_val = -1;
+
+	/* Try printing the newline */
+	zassert_equal(EC_ERROR_OVERFLOW, uart_puts(test_string));
+	zassert_equal(1, uart_tx_char_raw_fake.call_count);
+	zassert_equal('\r', uart_tx_char_raw_fake.arg1_val);
+}
+
+ZTEST(uart_printf, test_uart_put_raw_fail_tx)
+{
+	const char test_string[] = "\n";
+
+	uart_tx_char_raw_fake.return_val = -1;
+
+	/* Try printing the newline */
+	zassert_equal(0, uart_put_raw(test_string, 1));
+	zassert_equal(1, uart_tx_char_raw_fake.call_count);
+	zassert_equal('\n', uart_tx_char_raw_fake.arg1_val);
+}
+
+static int vfnprintf_custom_fake_expect_int_arg;
+static int vfnprintf_custom_fake(vfnprintf_addchar_t, void *, const char *,
+				 va_list alist)
+{
+	zassert_equal(vfnprintf_custom_fake_expect_int_arg, va_arg(alist, int));
+	return 0;
+}
+ZTEST(uart_printf, test_uart_printf)
+{
+	const char test_format[] = "d=%d";
+
+	vfnprintf_custom_fake_expect_int_arg = 5;
+	vfnprintf_fake.custom_fake = vfnprintf_custom_fake;
+
+	zassert_ok(
+		uart_printf(test_format, vfnprintf_custom_fake_expect_int_arg));
+	zassert_equal(1, vfnprintf_fake.call_count);
+	zassert_equal(test_format, vfnprintf_fake.arg2_val);
+}
diff --git a/zephyr/test/uart_printf/testcase.yaml b/zephyr/test/uart_printf/testcase.yaml
new file mode 100644
index 0000000000..0315abab6f
--- /dev/null
+++ b/zephyr/test/uart_printf/testcase.yaml
@@ -0,0 +1,8 @@
+# Copyright 2022 The ChromiumOS Authors
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+tests:
+  uart.printf:
+    tags: uart
+    type: unit