Feature: Dynamic Replacement

[GalloDaSballo]

• Allow a new panel that must be manually activated [ ] Enable Dynamic Replacement

• List out all CONSTANTS in Setup.sol in a new tab

• Show the current value

• Allow replacing the value in the Extension

• The extension will update the file and save before running the tool

• Save the change in the Recon.json

• Make the code in the Recon.json the same as our internal way of storing dynamic replacement

---

[GalloDaSballo]

@NehharShah do you have access to any resource that shows you how we represent dynamic replacement?

That's the only blocker from my side

FYI you can see a demo of how it works here:
https://getrecon.xyz/dynamic-replacement-demo

[GalloDaSballo]

@GalloDaSballo the only resource I know is: https://book.getrecon.xyz/using_recon/dynamic_replacement.html

Also, thanks for sharing the demo link

Yeah that's missing the underlying data representation we use in the runner.
I'll share it as soon as I can but likely in a few days

[GalloDaSballo]

@GalloDaSballo the only resource I know is: https://book.getrecon.xyz/using_recon/dynamic_replacement.html

Also, thanks for sharing the demo link

Actually here you go, here's a sample payload from a demo I did on running Gov Fuzzing with Dynamic Replacement on the Euler Codebase:

[
    {
        "config":"echidna.yaml",
        "govFuzz":true,
        "prepareContracts": [
            {
                "target":"newVault = IEVault",
                "replacement":"newVault = IEVault\\(NEW_VAULT\\);",
                "endOfTargetMarker":"[^;]*",
                "targetContract":"Setup.sol"
            },
            {
                "target":"controlTokenVault = IEVault",
                "replacement":"controlTokenVault = IEVault\\(CONTROL_TOKEN_VAULT\\);",
                "endOfTargetMarker":"[^;]*",
                "targetContract":"Setup.sol"
            },
            {
                "target":"evc = IEVC",
                "replacement":"evc = IEVC\\(EVC_ADDRESS\\);",
                "endOfTargetMarker":"[^;]*",
                "targetContract":"Setup.sol"
            },
            {
                "target":"underlying = IERC20",
                "replacement":"underlying = IERC20\\(UNDERLYING_TOKEN_ADDRESS\\);",
                "endOfTargetMarker":"[^;]*",
                "targetContract":"Setup.sol"
            },
            {
                "target":"controlToken = IERC20",
                "replacement":"controlToken = IERC20\\(CONTROL_TOKEN_ADDRESS\\);",
                "endOfTargetMarker":"[^;]*",
                "targetContract":"Setup.sol"
            },
            {
                "target":"underlyingWhale =",
                "replacement":"underlyingWhale = UNDERLYING_WHALE_ADDRESS;",
                "endOfTargetMarker":"[^;]*",
                "targetContract":"Setup.sol"
            },
            {
                "target":"controlTokenWhale =",
                "replacement":"controlTokenWhale = CONTROL_WHALE_ADDRESS;",
                "endOfTargetMarker":"[^;]*",
                "targetContract":"Setup.sol"
            }
        ],
        "contract":"CryticTester",
        "forkMode":"CHAIN",
        "testMode":"assertion",
        "corpusDir":"",
        "forkReplacement":true,
        "testLimit":"10000",
        "preprocess":null,
        "pathToTester":".",
        "targetCorpus":""
    }
]

For the purposes of Dynamic Replacement, the { target, replacement, endOfTargetMarker, targetContract } are the only relevant items and targetContract is hardcoded to Setup to avoid too much confusion

[sreeshanth-soma]

Hi @GalloDaSallo, thanks for sharing the sample dynamic replacement payload — that really helps clarify the underlying data representation.

I understand that for Dynamic Replacement the relevant fields are:

• target
• replacement
• endOfTargetMarker
• targetContract (currently Setup.sol)

If you’re okay with it, I’d like to take ownership of this issue.
My plan would be to:

• Add a new UI panel to list constants from Setup.sol
• Map edited values into the exact prepareContracts structure you shared
• Persist the data in Recon.json using the same internal format
• Apply the replacement before running the tool

I’ll treat targetContract as Setup.sol for now, as suggested.
Please let me know if you’re happy for me to proceed or if there’s anything I should account for before starting.

[Abu1982]

Hi, I'd like to work on this issue.

I've reviewed the thread and confirmed there is no active PR for it.

Planned approach: Analyze and fix based on error signals in Recon-Fuzz/recon-extension

I'll submit a focused PR once the fix is ready and locally verified.

[Abu1982]

Hi, I'd like to work on this issue.

I've reviewed the thread and confirmed there is no active PR for it.

Planned approach: Analyze and fix based on error signals in Recon-Fuzz/recon-extension

I'll submit a focused PR once the fix is ready and locally verified.

[Abu1982]

Hi, I'd like to work on this issue.

I've reviewed the thread and confirmed there is no active PR for it.

Planned approach: Analyze and fix based on error signals in Recon-Fuzz/recon-extension

I'll submit a focused PR once the fix is ready and locally verified.

[Abu1982]

Hi, I'd like to work on this issue.

I've reviewed the thread and confirmed there is no active PR for it.

Planned approach: Analyze and fix based on error signals in Recon-Fuzz/recon-extension

I'll submit a focused PR once the fix is ready and locally verified.