Add encodeToHex method to AbiFunction

Introduced encodeToHex method in AbiFunction to encode arguments into a hexadecimal string. Also added a unit test to verify the new method with Uniswap function encoding.
wkennedy · Jul 31, 2024 · ab2f598 · ab2f598
1 parent 59a8edd
commit ab2f598
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diff --git a/src/main/java/com/github/wkennedy/abi/entry/AbiFunction.java b/src/main/java/com/github/wkennedy/abi/entry/AbiFunction.java
@@ -3,10 +3,12 @@
 import com.github.wkennedy.abi.SolidityType;
 import com.github.wkennedy.util.ByteUtil;
 import org.apache.commons.codec.DecoderException;
+import org.apache.commons.codec.binary.Hex;
 import org.apache.commons.lang3.tuple.ImmutablePair;
 import org.apache.commons.lang3.tuple.Pair;
 
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
 
 import static com.github.wkennedy.abi.SolidityType.IntType.encodeInt;
@@ -28,10 +30,27 @@ public AbiFunction(boolean constant, String name, List<AbiParam> inputs, List<Ab
         super(null, constant, name, inputs, outputs, AbiType.function, payable);
     }
 
+    /**
+     * Encodes the given arguments into a byte array by merging the encoded signature and encoded arguments.
+     *
+     * @param args The arguments to encode.
+     * @return The encoded byte array.
+     */
     public byte[] encode(Object... args) {
         return ByteUtil.merge(encodeSignature(), encodeArguments(args));
     }
 
+    /**
+     * Encodes the given arguments into a hexadecimal string by merging the encoded signature and encoded arguments.
+     *
+     * @param args The arguments to encode.
+     * @return The encoded hexadecimal string.
+     */
+    public String encodeToHex(Object... args) {
+        byte[] methodBytes = encode(args);
+        return HEX_PREFIX + Hex.encodeHexString(methodBytes);
+    }
+
     private ImmutablePair<Integer, Integer> computeStaticSizeAndDynamicParams(Object... args) {
         int staticSize = 0;
         int dynamicCnt = 0;

diff --git a/src/test/java/com/github/wkennedy/abi/entry/AbiFunctionTest.java b/src/test/java/com/github/wkennedy/abi/entry/AbiFunctionTest.java
@@ -75,6 +75,21 @@ public void testUniswapFunctionDecode() throws IOException, DecoderException {
         assertEquals(BigInteger.valueOf(18), decode.getFirst());
     }
 
+    @Test
+    public void testUniswapFunctionEncode() throws IOException, DecoderException {
+        String abiJson = new String(Files.readAllBytes(Paths.get("./src/test/resources/uniswap_abi.json")));
+        Decoder decoder = new Decoder();
+        decoder.addAbi("0x731847de5b19b26039f283826ae5218ac7e070ed1b7fff689c2253a3035d8bd6", abiJson);
+        Predicate<AbiFunction> exists = fn -> fn.name.equals("getAmountsOut");
+        BigInteger amountIn = new BigInteger("1000000000000000000");
+        String[] path = {"0x0000000000000000000000000000456E65726779", "0x45429A2255e7248e57fce99E7239aED3f84B7a53"};
+
+        Optional<AbiFunction> function = decoder.getAbis().get("0x731847de5b19b26039f283826ae5218ac7e070ed1b7fff689c2253a3035d8bd6").findFunction(exists);
+        String encodeToHex = function.get().encodeToHex(amountIn, path);
+        assertNotNull(encodeToHex);
+        assertEquals("0xd06ca61f0000000000000000000000000000000000000000000000000de0b6b3a7640000000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000456e6572677900000000000000000000000045429a2255e7248e57fce99e7239aed3f84b7a53", encodeToHex);
+    }
+
     @Test
     void encode_withValidArgs_shouldReturnBytes() {
         AbiFunction testedAbiFunction = new AbiFunction(