* added unit tests for ConfigSerializer

test/mocks/Arduino.h

@@ -0,0 +1,3 @@
+#pragma once
+
+#include <Stream.h>

test/mocks/Stream.h

@@ -1,10 +1,71 @@
 #pragma once
 
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+
 // Mock Stream class for native testing
 // Provides minimal interface needed by Utils.h
 
-class Stream {
+#define DEC 10
+#define HEX 16
+#define OCT 8
+#define BIN 2
+
+class Print
+{
 public:
-    virtual void print(char c) {}
-    virtual void print(const char* str) {}
+    virtual size_t write(uint8_t b) { return 1; }
+    size_t write(const char *str)
+    {
+        if(str == NULL) {
+            return 0;
+        }
+        return write((const uint8_t *) str, strlen(str));
+    }
+    virtual size_t write(const uint8_t *buffer, size_t size) { 
+        size_t t = 0;
+        for (int i = 0; i < size; i++) { t += write(buffer[i]); }
+        return t;
+    }
+    size_t write(const char *buffer, size_t size)
+    {
+        return write((const uint8_t *) buffer, size);
+    }
+
+    virtual size_t print(unsigned char b, int r = DEC) { return 0; }
+    virtual size_t print(int v, int r = DEC) { return 0; }
+    virtual size_t print(unsigned int v, int r = DEC) { return 0; }
+    virtual size_t print(long v, int r = DEC) { return 0; }
+    virtual size_t print(unsigned long v, int r = DEC) { return 0; }
+    virtual size_t print(long long v, int r = DEC) { return 0; }
+    virtual size_t print(unsigned long long v, int r = DEC) { return 0; }
+    virtual size_t print(double v, int p = 2) { return 0; }
+
+    size_t print(char c) { return write(c); }
+    size_t print(const char* str) { return write(str); }
+
+    //size_t println(void)  { return 0; }
+    
+    virtual void flush() { /* Empty implementation for backward compatibility */ }    
 };
+
+class Stream: public Print
+{
+public:
+    virtual int available() { return 0; }
+    virtual int read() { return -1; }
+    virtual int peek() { return 0; }
+
+    virtual size_t readBytes(char *buffer, size_t length) { 
+        size_t i = 0;
+        while (i < length && available()) {
+            buffer[i++] = read();
+        }
+        return i;
+    }
+    virtual size_t readBytes(uint8_t *buffer, size_t length)
+    {
+        return readBytes((char *) buffer, length);
+    }
+};