chore: move to lib/bytes

foundry/lib/bytes/LibPrefixLengthEncodedByteArray.sol

@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.28;
+
+/**
+ * @title Propellerheads PrefixLengthEncoded Byte Array Library
+ * @author PropellerHeads Developers
+ * @dev Provide a gas efficient encoding for bytes array.
+ *
+ * Array of bytes are encoded as a single bytes like this :
+ *       16 bits      ??bits       16bits        ??bits ...
+ *   [length(elem1)]  [elem1]  [length(elem2)]  [elem2] ...
+ *
+ * This is much more efficient and compact than default solidity encoding.
+ */
+library LibPrefixLengthEncodedByteArray {
+    /**
+     * @dev Pop the first element of an array and returns it with the remaining data.
+     */
+    function next(bytes calldata encoded)
+        internal
+        pure
+        returns (bytes calldata elem, bytes calldata res)
+    {
+        assembly {
+            switch iszero(encoded.length)
+            case 1 {
+                elem.offset := 0
+                elem.length := 0
+                res.offset := 0
+                res.length := 0
+            }
+            default {
+                let l := shr(240, calldataload(encoded.offset))
+                elem.offset := add(encoded.offset, 2)
+                elem.length := l
+                res.offset := add(elem.offset, l)
+                res.length := sub(sub(encoded.length, l), 2)
+            }
+        }
+    }
+
+    /**
+     * @dev Gets the size of the encoded array.
+     */
+    function size(bytes calldata encoded) internal pure returns (uint256 s) {
+        assembly {
+            let offset := encoded.offset
+            let end := add(encoded.offset, encoded.length)
+            for {} lt(offset, end) {} {
+                offset := add(offset, add(shr(240, calldataload(offset)), 2))
+                s := add(s, 1)
+            }
+        }
+    }
+
+    /**
+     * @dev Cast an encoded array into a Solidity array.
+     */
+    function toArray(bytes calldata encoded)
+        internal
+        pure
+        returns (bytes[] memory arr)
+    {
+        bytes calldata elem;
+        uint256 idx = 0;
+        arr = new bytes[](LibPrefixLengthEncodedByteArray.size(encoded));
+        while (encoded.length > 0) {
+            (elem, encoded) = LibPrefixLengthEncodedByteArray.next(encoded);
+            arr[idx] = elem;
+            idx++;
+        }
+    }
+}