Testing with Nullables | Agent Skills Atlas

About this skill

Guides writing fast, reliable, refactoring-friendly tests using the Nullables pattern language (James Shore's 'Testing Without Mocks'). Produces narrow, sociable, state-based tests with production code that has an infrastructure 'off switch' — no mock frameworks needed. Use when writing tests, replacing mocks with Nullables, making infrastructure code testable, adding createNull() factories, implementing output tracking, wrapping external dependencies, or adopting testing-without-mocks patterns. Covers embedded stubs, configurable responses, behavior simulation, A-Frame architecture, and incremental migration from mock-based test suites.

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0 potential findings · Scanned 11/4/2026 · Scanner 0.2.1

Content SHA-256: 15c94272fff48c56180867e3e2b94369d49722c0561107de30ea8615ecd6bea2

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Original listing metadata

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testing-with-nullables

Original description

About this listing

Category: Engineering
Reported license: Not specified
Listing language (estimated): English
Review status: Not individually reviewed
Agent compatibility: Atlas installation supports Claude Code, Codex, and Cursor. Skill-specific dependencies and features are checked during setup.