recursive-tdd

recursive-tdd

Overview

Test-Driven Development is mandatory for all recursive-mode implementation work. This skill ensures test-first discipline is followed rigorously and recorded in a way recursive-mode tooling can verify.

Core Principle: If you didn't watch the test fail, you don't know if it tests the right thing.

The Iron Law for recursive-mode:

NO PRODUCTION CODE WITHOUT A FAILING TEST FIRST

Trigger examples

• Implement Phase 3 for run '<run-id>'
• Add a failing regression test first, then fix the bug
• I already wrote the code; now add tests (should trigger TDD reset guidance)
• Follow RED-GREEN-REFACTOR for this change

When to Use

Always in Phase 3 (Implementation):

• New features
• Bug fixes
• Refactoring
• Behavior changes

Default rule:

• Not for "simple" changes
• Not when "under pressure"
• Not because "tests after achieve same goals"

Explicit exception path only:

• If strict RED-first flow is genuinely infeasible, declare TDD Mode: pragmatic in the Phase 3 artifact
• Record a concrete exception reason
• Record compensating validation evidence under /.recursive/run/<run-id>/evidence/
• Treat this as an explicit deviation, not a silent shortcut

RED-GREEN-REFACTOR Cycle

digraph tdd_cycle {
    rankdir=LR;
    red [label="RED\nWrite failing test", shape=box, style=filled, fillcolor="#ffcccc"];
    verify_red [label="Verify fails\ncorrectly", shape=diamond];
    green [label="GREEN\nMinimal code", shape=box, style=filled, fillcolor="#ccffcc"];
    verify_green [label="Verify passes\nAll green", shape=diamond];
    refactor [label="REFACTOR\nClean up", shape=box, style=filled, fillcolor="#ccccff"];
    record [label="Record in\nPhase 3 artifact", shape=box];

    red -> verify_red;
    verify_red -> green [label="yes"];
    verify_red -> red [label="wrong\nfailure"];
    green -> verify_green;
    verify_green -> refactor [label="yes"];
    verify_green -> green [label="no"];
    refactor -> verify_green [label="stay\ngreen"];
    verify_green -> record;
}