refactor: allow decoding abi errors

src/Utils/AbiDecoder.php

@@ -28,6 +28,20 @@ public function decodeFunctionData(string $data): array
         ];
     }
 
+    public function decodeError(string $data): string
+    {
+        $data = $this->stripHexPrefix($data);
+
+        $errorSelector = substr($data, 0, 8);
+
+        $abiItem = $this->findErrorBySelector($errorSelector);
+        if (! $abiItem) {
+            throw new Exception('Function selector not found in ABI: '.$errorSelector);
+        }
+
+        return $abiItem['name'];
+    }
+
     public static function decodeAddress(string $bytes, int $offset): array
     {
         $data         = substr($bytes, $offset, 32);
@@ -152,12 +166,31 @@ public static function decodeFunctionWithAbi(string $functionSignature, string $
     private function findFunctionBySelector(string $selector): ?array
     {
         foreach ($this->abi as $item) {
-            if ($item['type'] === 'function') {
-                $functionSignature = $this->getFunctionSignature($item);
-                $functionSelector  = substr($this->keccak256($functionSignature), 2, 8);
-                if ($functionSelector === $selector) {
-                    return $item;
-                }
+            if ($item['type'] !== 'function') {
+                continue;
+            }
+
+            $functionSignature = $this->getFunctionSignature($item);
+            $functionSelector  = substr($this->keccak256($functionSignature), 2, 8);
+            if ($functionSelector === $selector) {
+                return $item;
+            }
+        }
+
+        return null;
+    }
+
+    private function findErrorBySelector(string $selector): ?array
+    {
+        foreach ($this->abi as $item) {
+            if ($item['type'] !== 'error') {
+                continue;
+            }
+
+            $errorSignature = $this->getFunctionSignature($item);
+            $errorSelector  = substr($this->keccak256($errorSignature), 2, 8);
+            if ($errorSelector === $selector) {
+                return $item;
             }
         }
 

tests/Unit/Utils/AbiDecoderTest.php

@@ -359,3 +359,17 @@
         $param,
     ]);
 })->throws(Exception::class, 'Unsupported type: testing');
+
+test('should decode error payload', function () {
+    $decoder = new AbiDecoder();
+
+    $decodedData = $decoder->decodeError('cd03235e');
+
+    expect($decodedData)->toBe('CallerIsNotValidator');
+});
+
+test('should throw exception if error payload does not exist', function () {
+    $decoder = new AbiDecoder();
+
+    $decoder->decodeError('123456');
+})->throws(Exception::class, 'Function selector not found in ABI: 123456');