[#6] cover the cryptography module with junit tests

Signed-off-by: Ori Bruk <o.bruk@yadro.com>

cryptography/src/test/java/info/frostfs/sdk/Base58Test.java

@@ -0,0 +1,54 @@
+package info.frostfs.sdk;
+
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+public class Base58Test {
+    private static final String WIF = "L1YS4myg3xHPvi3FHeLaEt7G8upwJaWL5YLV7huviuUtXFpzBMqZ";
+    private static final byte[] DECODE = new byte[]{
+            -128, -128, -5, 30, -36, -118, 85, -67, -6, 81, 43, 93, -38, 106, 21, -88, 127, 15, 125, -79, -17, -40, 77,
+            -15, 122, -88, 72, 109, -47, 125, -80, -40, -38, 1
+    };
+
+    @Test
+    void base58DecodeEncode() {
+        //When + Then
+        assertEquals(WIF, Base58.base58CheckEncode(Base58.base58CheckDecode(WIF)));
+    }
+
+    @Test
+    void base58Decode_success() {
+        //When
+        var decode = Base58.base58CheckDecode(WIF);
+
+        //Then
+        assertThat(decode).hasSize(34).containsExactly(DECODE);
+    }
+
+    @Test
+    void base58Decode_wrong() {
+        //When + Then
+        assertThrows(IllegalArgumentException.class, () -> Base58.base58CheckDecode(null));
+        assertThrows(IllegalArgumentException.class, () -> Base58.base58CheckDecode(""));
+        assertThrows(IllegalArgumentException.class, () -> Base58.base58CheckDecode("WIF"));
+        assertThrows(IllegalArgumentException.class, () -> Base58.base58CheckDecode("fh"));
+    }
+
+    @Test
+    void base58Encode_success() {
+        //When
+        var encode = Base58.base58CheckEncode(DECODE);
+
+        //Then
+        assertEquals(WIF, encode);
+    }
+
+    @Test
+    void base58Encode_wrong() {
+        //When + Then
+        assertThrows(IllegalArgumentException.class, () -> Base58.base58CheckEncode(null));
+    }
+}