Adding Code Coverage to Anchor Programs 🎯

This guide explains how to set up code coverage analysis for your Anchor program. 📊

Prerequisites

Install llvm (preferably version 19+)

Ubuntu

sudo apt install llvm

MacOS

brew install llvm

Setup Steps 🛠️

1. Add the solana-coverage crate to your program: 📦

cd programs/your_program
cargo add solana-coverage

2. Modify your program's lib.rs to include the coverage macro: 🔧

#[cfg(not(target_os = "solana"))]
mod coverage {
    use super::*;
    use anchor_lang::solana_program::{
        entrypoint::ProgramResult,
        program_stubs::{set_syscall_stubs, SyscallStubs},
    };
    solana_coverage::anchor_coverage!();
}

#[program]
pub mod my_anchor_program {
...
}

3. [OPTIONAL] For third-party program binaries (if using CPI) create (if missing) and use: 📁 tests/fixtures

4. Build an enhanced version of anchor-cli that supports code coverage for Anchor programs:

git clone https://github.com/LimeChain/anchor
cd anchor && cargo build

5. Build an enhanced version of LiteSVM that supports code coverage:

Don't clone litesvm inside the anchor-coverage-example clone directory. Please clone it outside of it as this may break tests.

git clone https://github.com/LimeChain/litesvm
cd litesvm/crates/node-litesvm && yarn && yarn build

Finally in order for the Typescript tests to use the enhanced version of LiteSVM we've just built, create a symbolic link to it at the root directory of the anchor workspace. Be sure to use full path:

ln -s /path/to/enhanced/litesvm/crates/node-litesvm/litesvm local-litesvm

Getting started 🚀

Add your program and third-party programs to test coverage in your test file:

// Be sure to use the enhanced LiteSVM
import {
  FailedTransactionMetadata,
  LiteSVM,
  TransactionMetadata,
} from "../local-litesvm";

// In your test file
describe("your_program", () => {
  before(async () => {
    // ... other setup code ...

    // LiteSVM setup
    svm.addProgramFromFile(programID, "target/deploy/your_program.so");
    svm.addProgramFromFile(
      thirdPartyProgramID,
      "tests/fixtures/third_party.so"
    ); // Add third party programs (if any)

    // Enable coverage tracking
    svm.withCoverage(
      [["your_program", programID.toBuffer()]],
      [["third_party", thirdPartyProgramID.toBuffer()]],
      payer.secretKey // add payer
    );
  });
  // ... your tests ...
});

Generate test coverage report:

RUST_BACKTRACE=1 RUST_LOG=info path/to/enhanced/anchor/target/debug/anchor coverage

Supported environment variables that anchor-cli will interpret if user is willing to specify the path to specific tools used for code coverage generation:

LLVM_COV=llvm-cov-19 # default: llvm-cov
LLVM_PROFDATA=llvm-profdata-19 # default: llvm-profdata
HTML_VIEWER=/bin/true # default: open

Example

The current repo showcases a simple vault program with code coverage enabled.
To test it create the symbolic link to the enhanced liteSVM (step 5) and generate the coverage with the enhanced Anchor CLI (step 4 and Coverage section). Also be sure to have everything from the Prerequisites section installed.