Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add rules/prisma/prisma-next/prefer-direct-imports-over-module-mocksgit clone --depth 1 https://github.com/prisma/prisma-nextWhat it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00000 | $0.01465 |
| Opus 5 | $0.00000 | $0.00732 |
| Sonnet 5 | $0.00000 | $0.00293 |
| Haiku 4.5 | $0.00000 | $0.00146 |
Grade A, and why
prefer-direct-imports-over-module-mocks scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
This is a copy
100% identical to prefer-direct-imports-over-module-mocks — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 101 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Prefer direct unit imports over module mocks in tests
When you reach for vi.mock / vi.hoisted / vi.resetModules / vi.setConfig to make a piece of production code testable, stop and ask: can the production code be factored so the test imports the unit it cares about directly?
The usual symptoms that you're about to write the wrong shape:
- A test file with
vi.mock('../../src/some-helper')because the unit under test callssome-helperas a side effect. - A test file with
vi.resetModules()inbeforeEachto force re-evaluation of a module whose state leaks across tests. - A test file with
vi.setConfig({ testTimeout, hookTimeout })at module scope because cold-importing the unit on every test is too slow. - A test file with
await import('…')inside a helper "so the mock is wired before module evaluation" —vi.mockis hoisted by vitest; a top-level static import sees the mock just fine. This pattern is almost always a misconception.
These are all signals that the production code has an entanglement (typically: config loading, environment access, time, or a stateful singleton) that's making the testable core hard to reach.
The fix
Extract a pure-ish core from the entangled wrapper:
- Pure-ish core function — takes the resolved inputs directly (e.g.
{ migrationsDir, spaceFilter }, notawait loadConfig()), returns a result object or throws structured errors. No side effects beyond what the test's tmpdir or fixture owns. - Thin wrapper — the CLI command builder / HTTP handler / scheduler hook — calls the entanglement (
loadConfig,process.env,Date.now(), the singleton getter), resolves inputs, delegates to the core. One screen of code, no branching.
Tests import the core directly. Zero vi.* plumbing. If the wrapper is genuinely just resolve-inputs-and-call-core, you can skip wrapper tests entirely — the build closes the gap.
When module mocks are legitimately the right tool
Some entanglements can't be cleanly extracted:
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- yesterday First seen · 101 lines · 0 tokens per session scan A a8fc6ddd4b53
prefer-direct-imports-over-module-mocks is a cursor rule published in the GitHub repository prisma/prisma-next (421 stars, last pushed 7d ago), licensed Apache-2.0. It costs nothing until one of its globs matches a file; then it loads 1,465 tokens. A static security scan graded it A with 0 findings. It is 100% identical to prefer-direct-imports-over-module-mocks, differing in 0 lines, and is treated as a copy.
Other cursor rules, from other repositories
cli-error-handling
CLI command error handling patterns.
prefer-direct-imports-over-module-mocks
Prefer extracting a testable core over vi.mock / vi.resetModules when unit tests need to reach production logic entangled with config, env, or singletons.
control-plane-descriptors
Control plane descriptor and instance implementation patterns.
directory-layout
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family-instance-domain-actions
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import-validation
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