The fe test Runner

The fe test command discovers, compiles, and runs all #[test] functions.

Basic Usage

Run all tests in a file:

fe test my_contract.fe

Run all tests in an ingot (directory with fe.toml):

fe test path/to/my-ingot/

Run tests matching a pattern:

fe test --filter transfer my_contract.fe

Filtering Tests

The --filter option matches against test function names. Only tests containing the filter string run:

# Run only tests with "balance" in the name
fe test --filter balance my_contract.fe

# Run only tests with "overflow" in the name
fe test --filter overflow my_contract.fe

Parallelism

Tests run in parallel by default (8 workers). Control this with --jobs:

# Run tests sequentially
fe test --jobs 1 my_contract.fe

# Use 16 parallel workers
fe test --jobs 16 my_contract.fe

Glob Patterns

Test multiple files at once using glob patterns:

# All .fe files in a directory
fe test "tests/*.fe"

# All test files recursively
fe test "src/**/*.fe"

Workspace Testing

In a workspace with multiple ingots, test a specific member:

# Test a specific ingot by name
fe test --ingot my-lib path/to/workspace/

Debugging Options

Event Logs

Show events emitted during test execution:

fe test --show-logs my_contract.fe

EVM Traces

Trace EVM opcodes for debugging:

fe test --trace-evm my_contract.fe

Call Traces

Show the call trace for each test:

fe test --call-trace my_contract.fe

Output Format

A typical test run looks like:

PASS  [0.0003s] test_max
PASS  [0.0003s] test_clamp
PASS  [0.0004s] test_counter_contract
FAIL  [0.0003s] test_broken
    Test reverted: 0x

test result: FAILED. 3 passed; 1 failed

failures:
    test_broken

• PASS — Test function completed without reverting
• FAIL — Test function reverted (or succeeded when should_revert was expected)
• The time shown is execution time, not compilation time

Summary of CLI Options

Option	Description
--filter PATTERN	Only run tests matching pattern
--jobs N	Parallel worker count (default: 8)
--show-logs	Display emitted event logs
--trace-evm	Trace EVM opcodes
--call-trace	Print call traces
--ingot NAME	Test specific workspace member
--backend yul|sonatina	Codegen backend (default: sonatina)
--optimize 0|s|2	Optimization level