Updated on 2026-08-14

core/utils/build.gradle.kts

@@ -4,6 +4,10 @@ plugins {
     id("configuration")
 }
 
+tasks.withType<Test>().configureEach {
+    useJUnitPlatform()
+}
+
 dependencies {
 
     // region DI
@@ -18,4 +22,9 @@ dependencies {
     // region Time dependencies
     implementation(deps.jodatime)
     // endregion
+
+    testImplementation(deps.test.junit5)
+    testRuntimeOnly(deps.test.junit5.engine)
+    testImplementation(deps.test.truth)
+    testImplementation(deps.test.mockk)
 }

core/utils/src/test/kotlin/com/tangem/utils/extensions/ByteArrayExtTest.kt

@@ -0,0 +1,115 @@
+package com.tangem.utils.extensions
+
+import com.google.common.truth.Truth
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.TestInstance
+
+/**
+[REDACTED_AUTHOR]
+ */
+@TestInstance(TestInstance.Lifecycle.PER_CLASS)
+class ByteArrayExtTest {
+
+    @Test
+    fun `toHexString converts byte array to hexadecimal string`() {
+        // Arrange
+        val byteArray = byteArrayOf(0x0F, 0xA5.toByte(), 0xFF.toByte())
+
+        // Act
+        val actual = byteArray.toHexString()
+
+        // Assert
+        val expected = "0FA5FF"
+        Truth.assertThat(actual).isEqualTo(expected)
+    }
+
+    @Test
+    fun `hexToBytes converts hexadecimal string to byte array`() {
+        // Arrange
+        val hexString = "0FA5FF"
+
+        // Act
+        val actual = hexString.hexToBytes()
+
+        // Assert
+        val expected = byteArrayOf(0x0F, 0xA5.toByte(), 0xFF.toByte())
+        Truth.assertThat(actual).isEqualTo(expected)
+    }
+
+    @Test
+    fun `hexToBytes handles hex string with prefix`() {
+        // Arrange
+        val hexString = "0x0FA5FF"
+
+        // Act
+        val actual = hexString.hexToBytes()
+
+        // Assert
+        val expected = byteArrayOf(0x0F, 0xA5.toByte(), 0xFF.toByte())
+        Truth.assertThat(actual).isEqualTo(expected)
+    }
+
+    @Test
+    fun `hexToBytes throws exception for invalid hex string`() {
+        // Arrange
+        val invalidHexString = "GHIJKL"
+
+        // Act
+        val actual = runCatching { invalidHexString.hexToBytes() }.exceptionOrNull()
+
+        // Assert
+        val expected = NumberFormatException()
+        Truth.assertThat(actual).isInstanceOf(expected::class.java)
+        Truth.assertThat(actual).hasMessageThat().isEqualTo("For input string: \"GH\" under radix 16")
+    }
+
+    @Test
+    fun `hexToBytes handles empty string`() {
+        // Arrange
+        val emptyHexString = ""
+
+        // Act
+        val actual = emptyHexString.hexToBytes()
+
+        // Assert
+        Truth.assertThat(actual).isEqualTo(byteArrayOf())
+    }
+
+    @Test
+    fun `hexToBytesOrNull returns byte array for valid hex string`() {
+        // Arrange
+        val hexString = "0FA5FF"
+
+        // Act
+        val actual = hexString.hexToBytesOrNull()
+
+        // Assert
+        val expected = byteArrayOf(0x0F, 0xA5.toByte(), 0xFF.toByte())
+        Truth.assertThat(actual).isEqualTo(expected)
+    }
+
+    @Test
+    fun `hexToBytesOrNull returns null for invalid hex string`() {
+        // Arrange
+        val invalidHexString = "GHIJKL"
+
+        // Act
+        val actual = invalidHexString.hexToBytesOrNull()
+
+        // Assert
+        Truth.assertThat(actual).isNull()
+    }
+
+    @Test
+    fun hexToBytesOrNullHandlesEmptyString() {
+        // Arrange
+        val emptyHexString = ""
+
+        // Act
+        val actual = emptyHexString.hexToBytesOrNull()
+
+        // Assert
+        val expected = byteArrayOf()
+        Truth.assertThat(actual).isEqualTo(expected)
+    }
+}