Two way tests for multibase encoding and decoding

Author: odisseus

src/test/java/io/ipfs/multibase/MultibaseBadInputsTest.java

@@ -0,0 +1,23 @@
+package io.ipfs.multibase;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertNotEquals;
+
+public class MultibaseBadInputsTest {
+
+    @Test
+    public void invalidBase16Test() {
+        String example = "f012"; // hex string of odd length
+        byte[] output = Multibase.decode(example);
+        String encoded = Multibase.encode(Multibase.Base.Base16, output);
+        assertNotEquals(example, encoded);
+    }
+
+    @Test (expected = NumberFormatException.class)
+    public void invalidWithExceptionBase16Test() {
+        String example = "f0g"; // g char is not allowed in hex
+        Multibase.decode(example);
+    }
+
+}

src/test/java/io/ipfs/multibase/MultibaseTest.java

@@ -3,73 +3,82 @@
 import org.junit.Test;
 
 import java.util.Arrays;
-import java.util.List;
+import java.util.Collection;
 
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNotEquals;
+import static org.junit.Assert.*;
 
+import org.junit.runner.RunWith;
+import org.junit.runners.Parameterized;
+import org.junit.runners.Parameterized.Parameters;
+
+@RunWith(Parameterized.class)
 public class MultibaseTest {
 
-    @Test
-    public void base58Test() {
-        List<String> examples = Arrays.asList(
-                "zQmPZ9gcCEpqKTo6aq61g2nXGUhM4iCL3ewB6LDXZCtioEB",
-                "zQmatmE9msSfkKxoffpHwNLNKgwZG8eT9Bud6YoPab52vpy",
-                "z11");
-        for (String example: examples) {
-            byte[] output = Multibase.decode(example);
-            String encoded = Multibase.encode(Multibase.Base.Base58BTC, output);
-            assertEquals(example, encoded);
-        }
-    }
+    private Multibase.Base base;
+    private byte[] raw;
+    private String encoded;
 
-    @Test
-    public void zeroBytesBase58() {
-        for (int i=0; i < 32; i++) {
-            String encoded = Multibase.encode(Multibase.Base.Base58BTC, new byte[i]);
-            byte[] output = Multibase.decode(encoded);
-            if (! Arrays.equals(output, new byte[i]))
-                throw new IllegalStateException("Failed to round trip zero array of length " + i);
-        }
+    public MultibaseTest(Multibase.Base base, byte[] raw, String encoded) {
+        this.base = base;
+        this.raw = raw;
+        this.encoded = encoded;
     }
 
-    @Test
-    public void base16Test() {
-        List<String> examples = Arrays.asList("f234abed8debede",
-                "f87ad873defc2b288",
-                "f",
-                "f01",
-                "f0123456789abcdef");
-        for (String example: examples) {
-            byte[] output = Multibase.decode(example);
-            String encoded = Multibase.encode(Multibase.Base.Base16, output);
-            assertEquals(example, encoded);
-        }
+    @Parameters(name = "{index}: {0}, {2}")
+    public static Collection<Object[]> data() {
+        return Arrays.asList(new Object[][]{
+                {Multibase.Base.Base58BTC, hexToBytes("1220120F6AF601D46E10B2D2E11ED71C55D25F3042C22501E41D1246E7A1E9D3D8EC"), "zQmPZ9gcCEpqKTo6aq61g2nXGUhM4iCL3ewB6LDXZCtioEB"},
+                {Multibase.Base.Base58BTC, hexToBytes("1220BA8632EF1A07986B171B3C8FAF0F79B3EE01B6C30BBE15A13261AD6CB0D02E3A"), "zQmatmE9msSfkKxoffpHwNLNKgwZG8eT9Bud6YoPab52vpy"},
+                {Multibase.Base.Base58BTC, new byte[1], "z1"},
+                {Multibase.Base.Base58BTC, new byte[2], "z11"},
+                {Multibase.Base.Base58BTC, new byte[4], "z1111"},
+                {Multibase.Base.Base58BTC, new byte[8], "z11111111"},
+                {Multibase.Base.Base58BTC, new byte[16], "z1111111111111111"},
+                {Multibase.Base.Base58BTC, new byte[32], "z11111111111111111111111111111111"},
+                {Multibase.Base.Base16, hexToBytes("234ABED8DEBEDE"), "f234abed8debede"},
+                {Multibase.Base.Base16, hexToBytes("87AD873DEFC2B288"), "f87ad873defc2b288"},
+                {Multibase.Base.Base16, hexToBytes(""), "f"},
+                {Multibase.Base.Base16, hexToBytes("01"), "f01"},
+                {Multibase.Base.Base16, hexToBytes("0123456789ABCDEF"), "f0123456789abcdef"},
+                {Multibase.Base.Base32, hexToBytes("01A195B1B1BC81DDBDC9B190"), "bnbswy3dpeb3w64tmmq"},
+                {Multibase.Base.Base32, hexToBytes("0005C44881FE0EC595FFC7F14EE4B7060522875977F0B52C7E8F59DCA12B77480049B641A4"), "bafyreid7qoywk77r7rj3slobqfekdvs57qwuwh5d2z3sqsw52iabe3mqne"},
+        });
     }
 
     @Test
-    public void base32Test() {
-        List<String> examples = Arrays.asList("bnbswy3dpeb3w64tmmq");
-        for (String example: examples) {
-            byte[] output = Multibase.decode(example);
-            String encoded = Multibase.encode(Multibase.Base.Base32, output);
-            assertEquals(example, encoded);
-        }
+    public void testEncode() {
+        String output = Multibase.encode(base, raw);
+        assertEquals(encoded, output);
     }
 
     @Test
-    public void invalidBase16Test() {
-        String example = "f012"; // hex string of odd length
-        byte[] output = Multibase.decode(example);
-        String encoded = Multibase.encode(Multibase.Base.Base16, output);
-        assertNotEquals(example, encoded);
+    public void testDecode() {
+        byte[] output = Multibase.decode(encoded);
+        assertArrayEquals(String.format("Expected %s, but got %s", bytesToHex(raw), bytesToHex(output)), raw, output);
+    }
 
+    //Copied from https://stackoverflow.com/a/140861
+    private static byte[] hexToBytes(String s) {
+        int len = s.length();
+        byte[] data = new byte[len / 2];
+        for (int i = 0; i < len; i += 2) {
+            data[i / 2] = (byte) ((Character.digit(s.charAt(i), 16) << 4)
+                    + Character.digit(s.charAt(i + 1), 16));
+        }
+        return data;
     }
 
-    @Test (expected = NumberFormatException.class)
-    public void invalidWithExceptionBase16Test() {
-        String example = "f0g"; // g char is not allowed in hex
-        Multibase.decode(example);
+    //Copied from https://stackoverflow.com/a/9855338
+    private static final char[] HEX_ARRAY = "0123456789ABCDEF".toCharArray();
+
+    private static String bytesToHex(byte[] bytes) {
+        char[] hexChars = new char[bytes.length * 2];
+        for (int j = 0; j < bytes.length; j++) {
+            int v = bytes[j] & 0xFF;
+            hexChars[j * 2] = HEX_ARRAY[v >>> 4];
+            hexChars[j * 2 + 1] = HEX_ARRAY[v & 0x0F];
+        }
+        return new String(hexChars);
     }
 
 }