add test

jfuse-api/src/test/java/org/cryptomator/jfuse/api/util/MemoryUtilsTest.java

@@ -0,0 +1,41 @@
+package org.cryptomator.jfuse.api.util;
+
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import java.lang.foreign.Arena;
+import java.lang.foreign.MemorySegment;
+
+public class MemoryUtilsTest {
+
+
+	@Test
+	@DisplayName("On MemorySegment != NULL pointer, method returns utf8 string in the memory region")
+	void testValidSegmentReturnsString() {
+		try (var arena = Arena.ofConfined()) {
+			var address = arena.allocate(4);
+			address.setUtf8String(0, "abc");
+			String result = MemoryUtils.toUtf8StringOrNull(address);
+			Assertions.assertEquals("abc", result);
+		}
+	}
+
+	@Test
+	@DisplayName("With offset, on MemorySegment != NULL pointer, method returns utf8 string in the memory region")
+	void testValidSegmentReturnsStringAtOffset() {
+		try (var arena = Arena.ofConfined()) {
+			var address = arena.allocate(10);
+			address.setUtf8String(5, "abc");
+			String result = MemoryUtils.toUtf8StringOrNull(address, 5);
+			Assertions.assertEquals("abc", result);
+		}
+	}
+
+	@Test
+	@DisplayName("When MemorySegment == NULL pointer, method returns null")
+	void testNullPointerSegmentReturnsNull() {
+		String result = MemoryUtils.toUtf8StringOrNull(MemorySegment.NULL, 0);
+		Assertions.assertNull(result);
+	}
+}