fix: better error for non-hex-prefixed hex strings

Closes #6070
Closes #6268

crates/cheatcodes/src/string.rs

@@ -116,5 +116,39 @@ where
 }
 
 fn parse_value(s: &str, ty: &DynSolType) -> Result<DynSolValue> {
-    ty.coerce_str(s).map_err(|e| fmt_err!("failed parsing {s:?} as type `{ty}`: {e}"))
+    match ty.coerce_str(s) {
+        Ok(value) => Ok(value),
+        Err(e) => match parse_value_fallback(s, ty) {
+            Some(Ok(value)) => Ok(value),
+            Some(Err(e2)) => Err(fmt_err!("failed parsing {s:?} as type `{ty}`: {e2}")),
+            None => Err(fmt_err!("failed parsing {s:?} as type `{ty}`: {e}")),
+        },
+    }
+}
+
+// More lenient parsers than `coerce_str`.
+fn parse_value_fallback(s: &str, ty: &DynSolType) -> Option<Result<DynSolValue, &'static str>> {
+    match ty {
+        DynSolType::Bool => {
+            let b = match s {
+                "1" => true,
+                "0" => false,
+                s if s.eq_ignore_ascii_case("true") => true,
+                s if s.eq_ignore_ascii_case("false") => false,
+                _ => return None,
+            };
+            return Some(Ok(DynSolValue::Bool(b)));
+        }
+        DynSolType::Int(_) |
+        DynSolType::Uint(_) |
+        DynSolType::FixedBytes(_) |
+        DynSolType::Bytes => {
+            if !s.starts_with("0x") && s.chars().all(|c| c.is_ascii_hexdigit()) {
+                return Some(Err("missing hex prefix (\"0x\") for hex string"))
+            }
+        }
+        DynSolType::String => return Some(Ok(DynSolValue::String(s.to_owned()))),
+        _ => {}
+    }
+    None
 }

crates/forge/tests/it/repros.rs

@@ -302,6 +302,12 @@ async fn test_issue_5808() {
     test_repro!("Issue5808");
 }
 
+// <https://github.com/foundry-rs/foundry/issues/6070>
+#[tokio::test(flavor = "multi_thread")]
+async fn test_issue_6070() {
+    test_repro!("Issue6070");
+}
+
 // <https://github.com/foundry-rs/foundry/issues/6115>
 #[tokio::test(flavor = "multi_thread")]
 async fn test_issue_6115() {

testdata/repros/Issue5808.t.sol

@@ -9,10 +9,9 @@ contract Issue5808Test is DSTest {
     Vm constant vm = Vm(HEVM_ADDRESS);
 
     function testReadInt() public {
-        // TODO: blocked on https://github.com/alloy-rs/core/issues/387
-        // string memory str1 = '["ffffffff","00000010"]';
-        // vm.expectRevert();
-        // int256[] memory ints1 = vm.parseJsonIntArray(str1, "");
+        string memory str1 = '["ffffffff","00000010"]';
+        vm.expectRevert();
+        int256[] memory ints1 = vm.parseJsonIntArray(str1, "");
 
         string memory str2 = '["0xffffffff","0x00000010"]';
         int256[] memory ints2 = vm.parseJsonIntArray(str2, "");

testdata/repros/Issue6070.t.sol

@@ -0,0 +1,16 @@
+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.18;
+
+import "ds-test/test.sol";
+import "../cheats/Vm.sol";
+
+// https://github.com/foundry-rs/foundry/issues/6070
+contract Issue6066Test is DSTest {
+    Vm constant vm = Vm(HEVM_ADDRESS);
+
+    function testNonPrefixed() public {
+        vm.setEnv("__FOUNDRY_ISSUE_6066", "abcd");
+        vm.expectRevert("failed parsing \"abcd\" as type `uint256`: missing hex prefix (\"0x\") for hex string");
+        uint256 x = vm.envUint("__FOUNDRY_ISSUE_6066");
+    }
+}