test(store): clean up Utils, add tests

packages/store/src/Memory.sol

@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: MIT
 pragma solidity >=0.8.0;
 
-import { Utils } from "./Utils.sol";
+import { leftMask } from "./Utils.sol";
 
 library Memory {
   function load(uint256 memoryPointer) internal pure returns (bytes32 data) {
@@ -49,7 +49,7 @@ library Memory {
         )
       }
     } else {
-      uint256 mask = Utils.leftMask(length);
+      uint256 mask = leftMask(length);
       assembly {
         mstore(
           toPointer,

packages/store/src/Storage.sol

@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: MIT
 pragma solidity >=0.8.0;
 
-import { Utils } from "./Utils.sol";
+import { leftMask } from "./Utils.sol";
 
 /**
  * TODO Probably not fully optimized
@@ -45,7 +45,7 @@ library Storage {
         wordRemainder = 32 - offset;
       }
 
-      uint256 mask = Utils.leftMask(length);
+      uint256 mask = leftMask(length);
       /// @solidity memory-safe-assembly
       assembly {
         // Load data from memory and offset it to match storage
@@ -91,7 +91,7 @@ library Storage {
 
     // For the last partial word, apply a mask to the end
     if (length > 0) {
-      uint256 mask = Utils.leftMask(length);
+      uint256 mask = leftMask(length);
       /// @solidity memory-safe-assembly
       assembly {
         sstore(
@@ -151,7 +151,7 @@ library Storage {
         wordRemainder = 32 - offset;
       }
 
-      uint256 mask = Utils.leftMask(wordRemainder);
+      uint256 mask = leftMask(wordRemainder);
       /// @solidity memory-safe-assembly
       assembly {
         // Load data from storage and offset it to match memory
@@ -195,7 +195,7 @@ library Storage {
 
     // For the last partial word, apply a mask to the end
     if (length > 0) {
-      uint256 mask = Utils.leftMask(length);
+      uint256 mask = leftMask(length);
       /// @solidity memory-safe-assembly
       assembly {
         mstore(

packages/store/src/StoreCore.sol

@@ -11,7 +11,6 @@ import { Slice, SliceLib } from "./Slice.sol";
 import { StoreMetadata, Hooks, HooksTableId } from "./codegen/Tables.sol";
 import { IStoreErrors } from "./IStoreErrors.sol";
 import { IStoreHook } from "./IStore.sol";
-import { Utils } from "./Utils.sol";
 import { TableId } from "./TableId.sol";
 
 library StoreCore {

packages/store/src/Utils.sol

@@ -1,27 +1,21 @@
 // SPDX-License-Identifier: MIT
 pragma solidity >=0.8.0;
 
-library Utils {
-  function divCeil(uint256 a, uint256 b) internal pure returns (uint256) {
-    return a / b + (a % b == 0 ? 0 : 1);
-  }
-
-  /**
-   * Adapted from https://github.com/dk1a/solidity-stringutils/blob/main/src/utils/mem.sol#L149-L167
-   * @dev Left-aligned byte mask (e.g. for partial mload/mstore).
-   * For byteLength >= 32 returns type(uint256).max
-   *
-   * length 0:   0x000000...000000
-   * length 1:   0xff0000...000000
-   * length 2:   0xffff00...000000
-   * ...
-   * length 30:  0xffffff...ff0000
-   * length 31:  0xffffff...ffff00
-   * length 32+: 0xffffff...ffffff
-   */
-  function leftMask(uint256 byteLength) internal pure returns (uint256) {
-    unchecked {
-      return ~(type(uint256).max >> (byteLength * 8));
-    }
+/**
+ * Adapted from https://github.com/dk1a/solidity-stringutils/blob/main/src/utils/mem.sol#L149-L167
+ * @dev Left-aligned byte mask (e.g. for partial mload/mstore).
+ * For byteLength >= 32 returns type(uint256).max
+ *
+ * length 0:   0x000000...000000
+ * length 1:   0xff0000...000000
+ * length 2:   0xffff00...000000
+ * ...
+ * length 30:  0xffffff...ff0000
+ * length 31:  0xffffff...ffff00
+ * length 32+: 0xffffff...ffffff
+ */
+function leftMask(uint256 byteLength) pure returns (uint256) {
+  unchecked {
+    return ~(type(uint256).max >> (byteLength * 8));
   }
 }

packages/store/test/Storage.t.sol

@@ -4,7 +4,6 @@ pragma solidity >=0.8.0;
 import { Test } from "forge-std/Test.sol";
 import { GasReporter } from "@latticexyz/gas-report/src/GasReporter.sol";
 import { Storage } from "../src/Storage.sol";
-import { Utils } from "../src/Utils.sol";
 import { Bytes } from "../src/Bytes.sol";
 
 contract StorageTest is Test, GasReporter {

packages/store/test/StoreCore.t.sol

@@ -4,7 +4,6 @@ pragma solidity >=0.8.0;
 import "forge-std/Test.sol";
 import { SchemaType } from "@latticexyz/schema-type/src/solidity/SchemaType.sol";
 import { StoreCore, StoreCoreInternal } from "../src/StoreCore.sol";
-import { Utils } from "../src/Utils.sol";
 import { Bytes } from "../src/Bytes.sol";
 import { TableId } from "../src/TableId.sol";
 import { SliceLib } from "../src/Slice.sol";

packages/store/test/StoreCoreGas.t.sol

@@ -5,7 +5,6 @@ import { Test } from "forge-std/Test.sol";
 import { GasReporter } from "@latticexyz/gas-report/src/GasReporter.sol";
 import { SchemaType } from "@latticexyz/schema-type/src/solidity/SchemaType.sol";
 import { StoreCore, StoreCoreInternal } from "../src/StoreCore.sol";
-import { Utils } from "../src/Utils.sol";
 import { Bytes } from "../src/Bytes.sol";
 import { SliceLib } from "../src/Slice.sol";
 import { EncodeArray } from "../src/tightcoder/EncodeArray.sol";

packages/store/test/Utils.t.sol

@@ -0,0 +1,35 @@
+// SPDX-License-Identifier: MIT
+pragma solidity >=0.8.0;
+
+import { Test } from "forge-std/Test.sol";
+import { GasReporter } from "@latticexyz/gas-report/src/GasReporter.sol";
+import { leftMask } from "../src/Utils.sol";
+
+contract UtilsTest is Test, GasReporter {
+  function testLeftMask() public {
+    bytes32 mask;
+    assertEq(leftMask(0), uint256(mask));
+    bytes32 highByte = hex"ff";
+    for (uint256 i = 1; i <= 32; i++) {
+      mask |= highByte;
+      highByte >>= 8;
+      assertEq(leftMask(i), uint256(mask));
+    }
+  }
+
+  function testFuzzLeftMaskOver32(uint256 byteLength) public {
+    // for values >32 the mask must always be type(uint256).max
+    vm.assume(byteLength > 32);
+    assertEq(leftMask(byteLength), type(uint256).max);
+  }
+
+  function testLeftMaskOver32() public {
+    // manually test for overflow issues
+    for (uint256 i; i < 100; i++) {
+      assertEq(leftMask(type(uint256).max - i), type(uint256).max);
+    }
+    for (uint256 i; i < 100; i++) {
+      assertEq(leftMask((type(uint256).max >> 8) + 50 - i), type(uint256).max);
+    }
+  }
+}