add unit-tests

Author: Katze719

.devcontainer/devcontainer.json

@@ -20,7 +20,9 @@
         "--privileged",
         "--device",
         "/dev/bus/usb:/dev/bus/usb",
-        "--device=/dev/ttyUSB0:/dev/ttyUSB0",
-        "--group-add=dialout"
+        "--device-cgroup-rule=c 188:* rwm",
+        "--device-cgroup-rule=c 166:* rwm",
+        "--group-add=dialout",
+        "--volume=/dev/serial/by-id:/dev/serial/by-id:ro"
     ]
 }

CMakeLists.txt

@@ -78,16 +78,28 @@ set_target_properties(${PROJECT_N} PROPERTIES
 
 target_include_directories(${PROJECT_N} PUBLIC ${PROJECT_SOURCE_DIR}/src)
 
-add_executable(serial_tests tests/serial_test.cpp)
-target_link_libraries(serial_tests PRIVATE ${PROJECT_N} gtest_main)
+add_executable(serial_integration_tests tests/serial_test.cpp)
+target_link_libraries(serial_integration_tests PRIVATE ${PROJECT_N} gtest_main)
 
-target_include_directories(serial_tests PRIVATE ${PROJECT_SOURCE_DIR}/src)
+target_include_directories(serial_integration_tests PRIVATE ${PROJECT_SOURCE_DIR}/src)
 
-add_custom_command(TARGET serial_tests POST_BUILD
+add_custom_command(TARGET serial_integration_tests POST_BUILD
     COMMAND ${CMAKE_COMMAND} -E copy_if_different
             $<TARGET_FILE:${PROJECT_N}>
-            $<TARGET_FILE_DIR:serial_tests>
+            $<TARGET_FILE_DIR:serial_integration_tests>
     COMMENT "Copy shared library next to test binary")
 
+# Unit test target covering additional API aspects
+add_executable(serial_unit_tests tests/serial_unit_tests.cpp)
+target_link_libraries(serial_unit_tests PRIVATE ${PROJECT_N} gtest_main)
+target_include_directories(serial_unit_tests PRIVATE ${PROJECT_SOURCE_DIR}/src)
+
+add_custom_command(TARGET serial_unit_tests POST_BUILD
+    COMMAND ${CMAKE_COMMAND} -E copy_if_different
+            $<TARGET_FILE:${PROJECT_N}>
+            $<TARGET_FILE_DIR:serial_unit_tests>
+    COMMENT "Copy shared library next to unit test binary")
+
 enable_testing()
-add_test(NAME SerialEchoTest COMMAND serial_tests /dev/ttyUSB0)
+add_test(NAME SerialEchoTest COMMAND serial_integration_tests /dev/ttyUSB0)
+add_test(NAME SerialUnitTests COMMAND serial_unit_tests)

tests/serial_unit_tests.cpp

@@ -0,0 +1,118 @@
+#include "serial.h"
+#include "status_codes.h"
+
+#include <atomic>
+#include <cstring>
+#include <gtest/gtest.h>
+#include <iostream>
+
+namespace
+{
+// Helper storage for callback tests
+std::atomic<int>* g_err_ptr = nullptr;
+
+void errorCallback(int code)
+{
+    if (g_err_ptr != nullptr)
+    {
+        *g_err_ptr = code;
+    }
+}
+} // namespace
+
+// ------------------------------- Error path --------------------------------
+TEST(SerialOpenTest, InvalidPathInvokesErrorCallback)
+{
+    std::atomic<int> err_code{0};
+
+    g_err_ptr = &err_code;
+    serialOnError(errorCallback);
+
+    intptr_t handle = serialOpen((void*)"/dev/__does_not_exist__", 115200, 8, 0, 0);
+    EXPECT_EQ(handle, 0);
+    EXPECT_EQ(err_code.load(), static_cast<int>(StatusCodes::INVALID_HANDLE_ERROR));
+
+    // Reset to nullptr so other tests don't see our callback
+    serialOnError(nullptr);
+}
+
+// ------------------------ serialGetPortsInfo checks ------------------------
+TEST(SerialGetPortsInfoTest, BufferTooSmallTriggersError)
+{
+    char sep[] = ";";
+    char buffer[4];
+    std::atomic<int> err_code{0};
+
+    g_err_ptr = &err_code;
+    serialOnError(errorCallback);
+
+    int res = serialGetPortsInfo(buffer, sizeof(buffer), sep);
+    EXPECT_EQ(res, 0); // function indicates failure via 0
+    EXPECT_EQ(err_code.load(), static_cast<int>(StatusCodes::BUFFER_ERROR));
+
+    serialOnError(nullptr);
+}
+
+TEST(SerialGetPortsInfoTest, LargeBufferReturnsZeroOrOne)
+{
+    char sep[] = ";";
+    char buffer[4096] = {0};
+
+    std::atomic<int> err_code{0};
+    g_err_ptr = &err_code;
+    serialOnError(errorCallback);
+
+    int res = serialGetPortsInfo(buffer, sizeof(buffer), sep);
+    EXPECT_GE(res, 0);
+    // res is 0 (no ports) or 1 (ports found)
+    EXPECT_LE(res, 1);
+    // Acceptable error codes: none or NOT_FOUND_ERROR (e.g., dir missing)
+    if (err_code != 0)
+    {
+        EXPECT_EQ(err_code.load(), static_cast<int>(StatusCodes::NOT_FOUND_ERROR));
+    }
+
+    serialOnError(nullptr);
+}
+
+// ---------------------------- Port listing helper ---------------------------
+TEST(SerialGetPortsInfoTest, PrintAvailablePorts)
+{
+    char sep[] = ";";
+    char buffer[4096] = {0};
+
+    int res = serialGetPortsInfo(buffer, sizeof(buffer), sep);
+    EXPECT_GE(res, 0);
+
+    std::string ports_str(buffer);
+    if (!ports_str.empty())
+    {
+        std::cout << "\nAvailable serial ports (by-id):\n";
+        size_t start = 0;
+        while (true)
+        {
+            size_t pos = ports_str.find(sep, start);
+            std::string token = ports_str.substr(start, pos - start);
+            std::cout << "  " << token << "\n";
+            if (pos == std::string::npos)
+            {
+                break;
+            }
+            start = pos + std::strlen(sep);
+        }
+    }
+    else
+    {
+        std::cout << "\nNo serial devices found in /dev/serial/by-id\n";
+    }
+}
+
+// --------------------------- Stubbed no-op APIs ----------------------------
+TEST(SerialStubbedFunctions, DoNotCrash)
+{
+    serialClearBufferIn(0);
+    serialClearBufferOut(0);
+    serialAbortRead(0);
+    serialAbortWrite(0);
+    SUCCEED(); // reached here without segfaults
+}