lastUpdated: "2026-01-11T13:09:48.217Z" lastCommit: "907d0b728b929259d4b202827743bf044de77fdd" lastCommitDate: "2026-01-11T10:45:33Z"

@open-harness/testing

Testing utilities for Open Harness signal-based architecture.

Status: Stub Package

This package is a placeholder for future testing utilities. The v0.2.0 utilities (MockRuntime, runtimeContract) were deleted as part of the v0.3.0 migration to signal-based providers.

Current Exports

import { MemorySignalStore, Player, type SignalStore } from "@open-harness/testing";

Re-exports core testing primitives for convenience.

Testing Signal-Based Code (v0.3.0)

Recording and Replay

import { MemorySignalStore, Player } from "@open-harness/testing";
import { runReactive } from "@open-harness/core";

// Record signals during execution
const store = new MemorySignalStore();
const result = await runReactive({
  agents: { myAgent },
  state: initialState,
  provider,
  signalStore: store,
});

// Replay with Player (VCR-style)
const player = new Player(result.signals);
player.step();  // Advance one signal
player.goto(5); // Jump to signal index 5

Mocking Providers

import { type Provider, createSignal } from "@open-harness/core";

const mockProvider: Provider = {
  run: async function* (input, ctx) {
    yield createSignal("harness:start", {});
    yield createSignal("text:delta", { delta: "Mock response" });
    yield createSignal("harness:end", { output: "Mock response" });
  },
};

Recommended: @open-harness/vitest

For Vitest-based testing with custom matchers, use @open-harness/vitest:

import { expect } from "vitest";
import { signalMatchers } from "@open-harness/vitest";

expect.extend(signalMatchers);

expect(result.signals).toContainSignal("agent:activated");
expect(result.signals).toHaveSignalsInOrder(["harness:start", "harness:end"]);

Planned Future Utilities

• Signal factories for common test patterns
• Provider mocking helpers
• Fixture recording/loading utilities
• Contract tests for custom providers

See Also

• @open-harness/vitest - Vitest matchers
• Testing example - Full test patterns