test: FoundryRandom tests

joejordan · Dec 22, 2022 · 1f95a9a · 1f95a9a
1 parent 2f94217
commit 1f95a9a
Showing 1 changed file with 154 additions and 0 deletions.
diff --git a/test/FoundryRandom.t.sol b/test/FoundryRandom.t.sol
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+// SPDX-License-Identifier: MIT
+pragma solidity >=0.8.4;
+
+import { console2 } from "forge-std/console2.sol";
+import { PRBTest } from "@prb/test/PRBTest.sol";
+
+import { BytesLib } from "solidity-bytes-utils/BytesLib.sol";
+import { CramBit } from "crambit/CramBit.sol";
+
+import { FoundryRandom } from "src/FoundryRandom.sol";
+
+/// @notice tests of our Foundry random number generators.
+contract FoundryRandomTest is PRBTest {
+    FoundryRandom public foundryRandom;
+
+    function setUp() public {
+        foundryRandom = new FoundryRandom();
+    }
+
+    /// @notice test the random number generator so that it returns values within the users' desired range
+    function testRandomNumber() public {
+        uint256 randomNum;
+
+        randomNum = foundryRandom.randomNumber(type(uint8).max);
+        assertLte(randomNum, type(uint8).max);
+
+        randomNum = foundryRandom.randomNumber(type(uint64).max);
+        assertLte(randomNum, type(uint64).max);
+
+        randomNum = foundryRandom.randomNumber(type(uint248).max);
+        assertLte(randomNum, type(uint248).max);
+
+        randomNum = foundryRandom.randomNumber(type(uint256).max);
+        assertLte(randomNum, type(uint256).max);
+
+        randomNum = foundryRandom.randomNumber(0);
+        assertEq(randomNum, 0);
+
+        randomNum = foundryRandom.randomNumber(1);
+        assertLte(randomNum, 1);
+
+        randomNum = foundryRandom.randomNumber(10);
+        assertLte(randomNum, 10);
+
+        randomNum = foundryRandom.randomNumber(123456789);
+        assertLte(randomNum, 123456789);
+    }
+
+    /// @notice fuzz test the random number generator
+    /// @dev ensure you have a decent number of fuzz rounds enabled in your foundry.toml file
+    /// ex: fuzz = { runs = 256 }
+    function testRandomNumberFuzz(uint256 maxVal) public {
+        uint256 randomNum;
+
+        randomNum = foundryRandom.randomNumber(maxVal);
+        assertLte(randomNum, maxVal);
+    }
+
+    /// @notice test the random number generator so that it returns values within the users' desired range
+    function testRandomNumberMinMax() public {
+        uint256 randomNum;
+
+        randomNum = foundryRandom.randomNumber(type(uint8).max, type(uint16).max);
+        assertGte(randomNum, type(uint8).max);
+        assertLte(randomNum, type(uint16).max);
+
+        randomNum = foundryRandom.randomNumber(type(uint64).max, type(uint128).max);
+        assertGte(randomNum, type(uint64).max);
+        assertLte(randomNum, type(uint128).max);
+
+        randomNum = foundryRandom.randomNumber(type(uint248).max, type(uint256).max);
+        assertGte(randomNum, type(uint248).max);
+        assertLte(randomNum, type(uint256).max);
+
+        randomNum = foundryRandom.randomNumber(0, type(uint256).max);
+        assertGte(randomNum, 0);
+        assertLte(randomNum, type(uint256).max);
+
+        randomNum = foundryRandom.randomNumber(0, 0);
+        assertEq(randomNum, 0);
+
+        randomNum = foundryRandom.randomNumber(1, 1);
+        assertEq(randomNum, 1);
+
+        randomNum = foundryRandom.randomNumber(0, 1);
+        assert(randomNum == 0 || randomNum == 1);
+
+        randomNum = foundryRandom.randomNumber(1, 2);
+        assert(randomNum == 1 || randomNum == 2);
+
+        randomNum = foundryRandom.randomNumber(123456789, 987654321);
+        assertGte(randomNum, 123456789);
+        assertLte(randomNum, 987654321);
+    }
+
+    /// @notice fuzz test the random number generator min max
+    /// @dev ensure you have a decent number of fuzz rounds enabled in your foundry.toml file
+    /// ex: fuzz = { runs = 256 }
+    function testRandomNumberMinMaxFuzz(uint256 minVal, uint256 maxVal) public {
+        vm.assume(maxVal >= minVal);
+        uint256 randomNum;
+
+        randomNum = foundryRandom.randomNumber(minVal, maxVal);
+        assertGte(randomNum, minVal);
+        assertLte(randomNum, maxVal);
+    }
+
+    /// @notice example on reusing a single random bytes32 multiple times for a series of smaller random uint ranges
+    function testRandomReuse() public {
+        uint256 randomUint;
+        // generate a single random bytes32 value
+        bytes32 randomBytes32 = foundryRandom.randomBytes32();
+        bytes32 remainingBytes32 = randomBytes32;
+
+        // reuse it multiple times
+        (randomUint, remainingBytes32) = foundryRandom.extractNumberFromBytes(10, randomBytes32);
+        console2.log("Random Uint (Max 10) = ", randomUint);
+        console2.log("Remaining Bytes:");
+        console2.logBytes32(remainingBytes32);
+
+        (randomUint, remainingBytes32) = foundryRandom.extractNumberFromBytes(100, remainingBytes32);
+        console2.log("Random Uint (Max 100) = ", randomUint);
+        console2.log("Remaining Bytes:");
+        console2.logBytes32(remainingBytes32);
+
+        (randomUint, remainingBytes32) = foundryRandom.extractNumberFromBytes(1000, remainingBytes32);
+        console2.log("Random Uint (Max 1000) = ", randomUint);
+        console2.log("Remaining Bytes:");
+        console2.logBytes32(remainingBytes32);
+
+        (randomUint, remainingBytes32) = foundryRandom.extractNumberFromBytes(100_000, remainingBytes32);
+        console2.log("Random Uint (Max 100_000) = ", randomUint);
+        console2.log("Remaining Bytes:");
+        console2.logBytes32(remainingBytes32);
+
+        (randomUint, remainingBytes32) = foundryRandom.extractNumberFromBytes(100_000_000, remainingBytes32);
+        console2.log("Random Uint (Max 100_000_000) = ", randomUint);
+        console2.log("Remaining Bytes:");
+        console2.logBytes32(remainingBytes32);
+
+        (randomUint, remainingBytes32) = foundryRandom.extractNumberFromBytes(100_000_000_000_000, remainingBytes32);
+        console2.log("Random Uint (Max 100_000_000_000_000) = ", randomUint);
+        console2.log("Remaining Bytes:");
+        console2.logBytes32(remainingBytes32);
+
+        (randomUint, remainingBytes32) = foundryRandom.extractNumberFromBytes(
+            100_000_000_000_000_000_000_000,
+            remainingBytes32
+        );
+        console2.log("Random Uint (Max 100_000_000_000_000_000_000_000) = ", randomUint);
+        console2.log("Remaining Bytes:");
+        console2.logBytes32(remainingBytes32);
+    }
+}