Quick start

Cairo Debugger is currently only distributed with snforge - a testing tool for Cairo, part of Starknet Foundry.

Installation

WARNING

Make sure to use a version >=0.60.0 of snforge - previous versions do not have the integrated debugger.

WARNING

Make sure to use a version >=2.18.0 of Scarb - previous versions cannot produce the required debug information nor display ▶ Debug Test code lens.

To make the Cairo Debugger work, you have to install:

1. snforge - a part of Starknet Foundry. Make sure to use version >=0.60.0
2. Scarb package manager. Make sure to use version >=2.18.0.
3. For Visual Studio Code, install the latest Cairo 1.0 extension from the marketplace. Make sure to use version >=3.6.0.

Prerequisites

Live debugging relies on debug information generated by Scarb. Make sure the cairo compiler configuration in your workspace Scarb.toml is equivalent to the following one:

[profile.dev.cairo]
skip-optimizations = true
add-statements-code-locations-debug-info = true
add-statements-functions-debug-info = true
add-functions-debug-info = true
add-types-debug-info = true

Usage

Visual Studio Code

Click the ▶ Debug Test code lens above the test function you want to debug - the Cairo extension will start a debugging session automatically.

See the Debugging in VSCode guide for a full step-by-step walkthrough.

Debugging in another IDE

If you are using another IDE, you need to make sure that your DAP client establishes the connection with snforge's debug adapter after it is launched. If you run:

$ snforge test --exact my_package::my_module::test_name --launch-debugger

snforge will start a TCP server and print the port it is listening on to stdout in the following format:

DEBUGGER PORT: 12345

Connect your DAP client to localhost on that port to begin the debugging session.

NOTE

--launch-debugger requires --exact - only a single test can be debugged at a time.

Troubleshooting

If you run into issues, see the Troubleshooting page.