fix(cheatcodes): add repro test for once reported issues around empty…

… JSON arrays (#7348)

* add repro case, fortunately issue has been resolved over time

* revert debug line

crates/forge/tests/it/repros.rs

@@ -176,6 +176,9 @@ test_repro!(3753);
 // https://github.com/foundry-rs/foundry/issues/3792
 test_repro!(3792);
 
+// https://github.com/foundry-rs/foundry/issues/4402
+test_repro!(4402);
+
 // https://github.com/foundry-rs/foundry/issues/4586
 test_repro!(4586);
 

testdata/fixtures/Json/Issue4402.json

@@ -0,0 +1,4 @@
+{
+  "tokens": ["0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2"],
+  "empty": []
+}

testdata/fixtures/Toml/Issue4402.toml

@@ -0,0 +1,2 @@
+tokens = ["0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2"]
+empty = []

testdata/repros/Issue4402.t.sol

@@ -0,0 +1,64 @@
+// SPDX-License-Identifier: MIT OR Apache-2.0
+pragma solidity 0.8.18;
+
+import "ds-test/test.sol";
+import "../cheats/Vm.sol";
+
+// https://github.com/foundry-rs/foundry/issues/4402
+contract Issue4402Test is DSTest {
+    Vm constant vm = Vm(HEVM_ADDRESS);
+
+    function testReadNonEmptyArray() public {
+        string memory path = "fixtures/Json/Issue4402.json";
+        string memory json = vm.readFile(path);
+        address[] memory tokens = vm.parseJsonAddressArray(json, ".tokens");
+        assertEq(tokens.length, 1);
+
+        path = "fixtures/Toml/Issue4402.toml";
+        string memory toml = vm.readFile(path);
+        tokens = vm.parseTomlAddressArray(toml, ".tokens");
+        assertEq(tokens.length, 1);
+    }
+
+    function testReadEmptyArray() public {
+        string memory path = "fixtures/Json/Issue4402.json";
+        string memory json = vm.readFile(path);
+
+        // Every one of these used to causes panic
+        address[] memory emptyAddressArray = vm.parseJsonAddressArray(json, ".empty");
+        bool[] memory emptyBoolArray = vm.parseJsonBoolArray(json, ".empty");
+        bytes[] memory emptyBytesArray = vm.parseJsonBytesArray(json, ".empty");
+        bytes32[] memory emptyBytes32Array = vm.parseJsonBytes32Array(json, ".empty");
+        string[] memory emptyStringArray = vm.parseJsonStringArray(json, ".empty");
+        int256[] memory emptyIntArray = vm.parseJsonIntArray(json, ".empty");
+        uint256[] memory emptyUintArray = vm.parseJsonUintArray(json, ".empty");
+
+        assertEq(emptyAddressArray.length, 0);
+        assertEq(emptyBoolArray.length, 0);
+        assertEq(emptyBytesArray.length, 0);
+        assertEq(emptyBytes32Array.length, 0);
+        assertEq(emptyStringArray.length, 0);
+        assertEq(emptyIntArray.length, 0);
+        assertEq(emptyUintArray.length, 0);
+
+        path = "fixtures/Toml/Issue4402.toml";
+        string memory toml = vm.readFile(path);
+
+        // Every one of these used to causes panic
+        emptyAddressArray = vm.parseTomlAddressArray(toml, ".empty");
+        emptyBoolArray = vm.parseTomlBoolArray(toml, ".empty");
+        emptyBytesArray = vm.parseTomlBytesArray(toml, ".empty");
+        emptyBytes32Array = vm.parseTomlBytes32Array(toml, ".empty");
+        emptyStringArray = vm.parseTomlStringArray(toml, ".empty");
+        emptyIntArray = vm.parseTomlIntArray(toml, ".empty");
+        emptyUintArray = vm.parseTomlUintArray(toml, ".empty");
+
+        assertEq(emptyAddressArray.length, 0);
+        assertEq(emptyBoolArray.length, 0);
+        assertEq(emptyBytesArray.length, 0);
+        assertEq(emptyBytes32Array.length, 0);
+        assertEq(emptyStringArray.length, 0);
+        assertEq(emptyIntArray.length, 0);
+        assertEq(emptyUintArray.length, 0);
+    }
+}