pf_test_harness

Caution

Native only — this crate requires tokio, axum, and reqwest and does not compile to WASM. It is excluded from WASM builds via #![cfg(not(target_arch = "wasm32"))].

Crate: pf_test_harness · Path: crates/pf_test_harness
Description (Cargo.toml): Reusable native test harness for PromptFleet streaming and SSE seams

Native-only. This crate is gated with #![cfg(not(target_arch = "wasm32"))] — it does not compile to WASM. It uses tokio, axum, reqwest, and other native-only dependencies for test infrastructure.

Role

Test harness for integration and seam testing of streaming pipelines, SSE wire format, and A2A JSON-RPC routes without mocks or real LLM calls. Provides deterministic LLM turn sequences, SSE frame capture and assertion helpers, end-to-end pipeline testing, and axum-based A2A route exercisers.

Feature flags

From crates/pf_test_harness/Cargo.toml:

Feature	Purpose
default	(empty — no features enabled by default)
scenario	LlmScenario and TurnScenarioBuilder for deterministic LLM turns (enables agent_sdk, axum)
sse	SseFrame, SseCapture, SseCollector for SSE frame capture and assertions
agent-sdk	Full pipeline testing: scenario + sse + agent_sdk integration + a2a_protocol_core + axum
a2a-http	A2A JSON-RPC body builders and route exercisers (a2a_http_server, a2a_protocol_core, axum, tower)
a2a-mock	Mock A2A server for integration tests (a2a_protocol_core, axum, tokio-stream, reqwest)

Public API (from src/lib.rs)

All modules are feature-gated:

• scenario (feature: scenario) — LlmScenario, TurnScenarioBuilder for deterministic LLM turn sequences (text, tool calls, errors, reasoning)
• scenario_openai_http (feature: scenario) — OpenAI-format HTTP scenario helpers
• sse (feature: sse) — SseFrame, SseCapture for collecting and asserting SSE frames (event names, JSON paths, terminal events)
• pipeline (feature: agent-sdk) — TestPipeline for end-to-end: scenario → engine → mapper → SSE capture
• perf (feature: agent-sdk) — Performance testing utilities
• a2a_http (feature: a2a-http) — JSON-RPC body builders (send_subscribe_body, message_send_body, tasks_get_body, tasks_cancel_body, tasks_list_body) + call_jsonrpc / collect_send_subscribe_sse for axum router testing
• a2a_mock (feature: a2a-mock) — Mock A2A server for integration testing

Example sketch

// Feature: scenario
use pf_test_harness::scenario::LlmScenario;

let scenario = LlmScenario::new()
    .turn(|t| t.content("Hello!").done("stop"))
    .turn(|t| t.tool_call("search", serde_json::json!({"q": "rust"})).done("tool_calls"));

// Feature: sse
use pf_test_harness::sse::SseCapture;

let capture: SseCapture = /* ... collect from response ... */;
capture.assert_sequence(&["message", "message", "done"]);

// Feature: a2a-http
use pf_test_harness::a2a_http::{send_subscribe_body, call_jsonrpc};

Full API reference: cargo doc -p pf_test_harness --no-deps --all-features