Tdd Rust

RTK TDD Workflow

Enforce Red-Green-Refactor for all RTK filter development.

The Loop

1. RED   — Write failing test with real fixture
2. GREEN — Implement minimum code to pass
3. REFACTOR — Clean up, verify still passing
4. SAVINGS — Verify ≥20% token reduction
5. SNAPSHOT — Lock output format with insta

Step 1: Real Fixture First

Never write synthetic test data. Capture real command output:

# Capture real output from the actual command
git log -20 > tests/fixtures/git_log_raw.txt
cargo test 2>&1 > tests/fixtures/cargo_test_raw.txt
cargo clippy 2>&1 > tests/fixtures/cargo_clippy_raw.txt
gh pr view 42 > tests/fixtures/gh_pr_view_raw.txt

# For commands with ANSI codes — capture as-is
script -q /dev/null cargo test 2>&1 > tests/fixtures/cargo_test_ansi_raw.txt

Fixture naming: tests/fixtures/<command>_raw.txt

Step 2: Write the Test (Red)

#[cfg(test)]
mod tests {
    use super::*;
    use insta::assert_snapshot;

    fn count_tokens(s: &str) -> usize {
        s.split_whitespace().count()
    }