implicit trailing / in remappings causes file remappings to not resolve

[BlazeWasHere]

Component

Forge

Have you ensured that all of these are up to date?

• Foundry
• Foundryup

What version of Foundry are you on?

forge 0.2.0 (d1ab09d 2024-03-30T00:17:25.901579435Z)

What command(s) is the bug in?

No response

Operating System

Linux

Describe the bug

Using remappings.txt

ds-test/=lib/ds-test/src/
src/test.sol=src/testPatched.sol

when ran with forge (notice how its src/test.sol/ instead of src/test.sol)

~> forge remappings 
ds-test/=lib/ds-test/src/
src/test.sol/=src/testPatched.sol/

expected behavior is similar to dapptools -- no trailing / is added to the remapping.

simple testcase:

A.t.sol

// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity ^0.8.6;

import "ds-test/test.sol";

import {Test} from "src/test.sol";

contract ATest is DSTest {
    function test_basic_sanity() public {
        Test.log();
        assertTrue(true);
    }
}

test.sol

// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity ^0.8.6;

library Test {
    event log_string(string);

    function log() internal {
        emit log_string("test");
    }
}

testPatched.sol

// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity ^0.8.6;

library Test {
    event log_string(string);

    function log() internal {
        emit log_string("patched");
    }
}

now we run forge:

~> forge test -vv
[⠊] Compiling...
No files changed, compilation skipped

Ran 1 test for src/A.t.sol:ATest
[PASS] test_basic_sanity() (gas: 1821)
Logs:
  test

with dapptools:

~> DAPP_REMAPPINGS=$(cat remappings.txt) dapp test --verbosity 2 
 dapp-build: building with linked libraries
dapp: Predeploying test library src/testPatched.sol:Test at 0x0DdeDfFe2789df61F5f76479464F568334414389
dapp: Predeploying test library src/test.sol:Test at 0x5Fe5dAc04fe3527Cf7bDba8798F5A8b5edDfE4Af
Running 1 tests for src/A.t.sol:ATest
[PASS] test_basic_sanity() (gas: 1994)

Success: test_basic_sanity
  
  "patched"

it does seem like this will be a breaking change if implemented due to some people who may be relying on this unexpected behavior, wdyt?

[BlazeWasHere]

seems like its caused by this

foundry/crates/config/src/utils.rs

Lines 172 to 180 in a16714e

	let mut r = Remapping {
	context: None,
	name: format!("{dir_name}/"),
	path: format!("{}", dir.display()),
	};
	if !r.path.ends_with('/') {
	r.path.push('/')
	}
	Some(r)

foundry/crates/config/src/providers/remappings.rs

Lines 216 to 226 in d94e3c6

	if let Some(name) = lib.file_name().and_then(|s| s.to_str()) {
	let mut r = Remapping {
	context: None,
	name: format!("{name}/"),
	path: format!("{}", lib.join(&config.src).display()),
	};
	if !r.path.ends_with('/') {
	r.path.push('/')
	}
	src_remapping = Some(r);
	}

this looks related https://github.com/foundry-rs/compilers/issues/47

[zerosnacks]

This seems related to #6706

you cannot remap individual files, only directories

[BlazeWasHere]

@zerosnacks i believe this issue was fixed in foundry-rs/compilers#49 and all tests passed in foundry CI #8377 so im guessing we are waiting for foundry main to update to the latest version of foundry-compilers

[zerosnacks]

Thanks @BlazeWasHere, looks like that should fix it!

I'll follow up on this once a new release of foundry-compilers is cut (should be relatively soon) and we have bumped the version in Foundry

[zerosnacks]

Marking as resolved as foundry-compilers has been updated: foundry-rs/compilers@ea34637 +

foundry/Cargo.toml

Line 161 in 4e4f35c

foundry-compilers = { version = "0.10.0", default-features = false }

[BlazeWasHere]

@zerosnacks doesnt look like original poc has been fixed with latest nightly (00ff367) + (37ea1e9). should i create a test case for this?

$ DAPP_REMAPPINGS=$(cat remappings.txt) dapp test --verbosity 2  
 dapp-build: building with linked libraries
[...]

  src/A.t.sol:ATest
   ├╴constructor
   └╴test_basic_sanity()
      ├╴log_string("patched") (src/testPatched.sol:8)
[...]
  
  "patched" # <--- this is good :)


$ forge test -vvv 
[...]
Logs:
  test # <--- this is bad :(

[zerosnacks]

Hi @BlazeWasHere, that would be appreciated. However I'm still not sure what the intended behavior here would be because Foundry does not support remapping individual files to my knowledge, only directories.

[BlazeWasHere]

@zerosnacks Correct that Foundry does not support individual file remappings, ideally it should (foundry-compilers does) but i think that's related to #6706