Feat (cheatcodes): Introducing ipfs cid v0 to calculate file content

Cargo.toml

@@ -314,6 +314,7 @@ url = "2"
 vergen = { version = "8", default-features = false }
 yansi = { version = "1.0", features = ["detect-tty", "detect-env"] }
 path-slash = "0.2"
+sha2 = "0.10"
 
 [patch.crates-io]
 ## alloy-core

crates/cheatcodes/Cargo.toml

@@ -62,3 +62,4 @@ tracing.workspace = true
 walkdir.workspace = true
 proptest.workspace = true
 serde.workspace = true
+sha2.workspace=true

crates/cheatcodes/spec/src/vm.rs

@@ -2008,6 +2008,10 @@ interface Vm {
     #[cheatcode(group = Filesystem)]
     function promptUint(string calldata promptText) external returns (uint256);
 
+    /// Calculates the IPFS CID V0 of a file's content.
+    #[cheatcode(group = Filesystem)]
+    function ipfsCidV0(string calldata filepath) external  returns (bytes32 cid);
+
     // ======== Environment Variables ========
 
     /// Sets environment variables.

crates/cheatcodes/src/fs.rs

@@ -15,6 +15,7 @@ use foundry_config::fs_permissions::FsAccessKind;
 use revm::interpreter::CreateInputs;
 use revm_inspectors::tracing::types::CallKind;
 use semver::Version;
+use sha2::{Digest, Sha256};
 use std::{
     io::{BufRead, BufReader, Write},
     path::{Path, PathBuf},
@@ -587,6 +588,19 @@ impl Cheatcode for promptUintCall {
     }
 }
 
+impl Cheatcode for ipfsCidV0Call {
+    fn apply(&self, _state: &mut Cheatcodes) -> Result {
+        let contents = fs::read(&self.filepath).unwrap();
+        let hash = Sha256::digest(&contents);
+        let mut multihash = Vec::with_capacity(2 + hash.len());
+        multihash.push(0x12);
+        multihash.push(0x20);
+        multihash.extend_from_slice(&hash);
+
+        Ok(multihash)
+    }
+}
+
 pub(super) fn write_file(state: &Cheatcodes, path: &Path, contents: &[u8]) -> Result {
     let path = state.config.ensure_path_allowed(path, FsAccessKind::Write)?;
     // write access to foundry.toml is not allowed

testdata/default/cheats/IpfsCidV0.t.sol

@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: MIT OR Apache-2.0
+pragma solidity ^0.8.18;
+
+import "ds-test/test.sol";
+import "cheats/Vm.sol";
+
+contract IpfsCidV0Test is DSTest {
+    Vm constant vm = Vm(HEVM_ADDRESS);
+
+    function testIpfsCidV0() public {
+        string memory filePath = "testdata/fixtures/File/test.txt";
+
+        bytes32 cid = vm.ipfsCidV0(filePath);
+
+        bytes32 expectedCid = 0x94da694df5cf2e139206cddcdd6f855baa45e519c5fdbc2e6aa1cf803cfd65d5;
+
+        assertEq(cid, expectedCid);
+    }
+}

testdata/fixtures/File/test.txt

@@ -0,0 +1,5 @@
+---
+title: TestTitle
+discussions: TestDiscussion
+author: TestAuthor
+---