Files
deepseek-harness/packages/support/acp-snapshot/src/suite.ts

385 lines
21 KiB
TypeScript

/**
* The ACP snapshot suite factory (REPLAY by default, keyless). A suite is a
* scenario table plus a snapshots directory: each scenario under
* `<snapshotsDir>/<name>/` ships an `input.json` (the client stdin script) and
* a `session.jsonl` fixture; replay boots the real agent subprocess
* (./harness.ts), drives it, and diffs the normalized stdout transcript
* against the committed `stdout.golden.jsonl`. For model scenarios it ALSO
* checks the re-persisted session log — against the `session.jsonl` fixture
* itself, not a separate golden: the fixture doubles as the replay source
* (recorded scenarios) and the expected produced log (both sides normalized
* before comparing).
*
* Request-header content (the composed system prompt + tool schemas riding on
* `request/header` events) is pinned by exactly ONE scenario per suite — the
* one with `pinsHeader` — and scrubbed to `{{system}}`/`{{tools}}` tokens in
* every other fixture and compare, so a prompt or tool-schema edit churns one
* committed line instead of every fixture. A per-run uniformity guard keeps
* the single pin sound: every live header must equal the pinned one, and no
* header-delta may appear outside the pinning scenario (see the
* pinned-header RFC,
* docs/rfc/implemented/testing/2026-07-06-pin-request-header-content-in-one-scenario.md).
*
* `pnpm run test:snapshot:record` (DSH_SNAPSHOT=record + -u) re-records the
* `session.jsonl` fixtures against the real API and refreshes the stdout golden
* in one pass; the caller resolves that env into {@link SnapshotSuiteOptions}
* (env reading stays at the suite edge, not in this library).
*
* @module @deepseek-ai/dsh-acp-snapshot/suite
*/
import { readFile, readdir, writeFile } from 'node:fs/promises'
import { existsSync } from 'node:fs'
import { join } from 'node:path'
import { describe, expect, it } from 'vitest'
import { type AgentUnderTest, type HarvestedLog, type InputScript, runScenario } from './harness.ts'
import { type NormalizeContext, normalizeSessionLog, normalizeStdout, scrubRequestHeaders } from './normalize.ts'
/** A snapshot scenario and how its fixtures are produced. */
export interface Scenario {
name: string
/** Whether the scenario drives at least one model turn (so a JSONL golden applies). */
hasModelTurn: boolean
/**
* Whether the run persists a comparable session log to diff against the
* `session.jsonl` fixture. Defaults to {@link hasModelTurn} (a model turn
* always produces a log worth comparing). Set it independently for a scenario
* that produces a non-trivial log WITHOUT a model turn — e.g. a prompt blocked
* by a `UserPromptSubmit` hook, which opens a `rejected` turn carrying `hook/*`
* events but never calls the model.
*/
comparesLog?: boolean
/**
* Whether `test:snapshot:record` regenerates this scenario's `session.jsonl`
* from the LIVE API. `recorded` scenarios are model-driven and reproducible;
* `authored` scenarios (fixtures hand-written or hand-harvested — e.g. a
* provider error or a cancel the live API can't be coaxed into
* deterministically, a deterministic hook scenario, or a scripted repetition
* a live model won't reproduce) are NEVER re-recorded.
*/
recorded: boolean
/**
* Whether replay is driven by a hand-written `replay.override.json` sidecar
* (a `ReplayEntry[]` that REPLACES the script derived from `session.jsonl`)
* — the throw/hang cases chunks cannot express. The fixture guard requires
* the sidecar exactly when this is set: the harness forwards the file purely
* on existence, so an unregistered stray sidecar would silently replace the
* derived script — the guard fails loud on either mismatch. Defaults to
* false (replay derives from the fixture's `assistant/chunk` events).
*/
overridden?: boolean
/**
* How many SUBAGENT child sessions this scenario records beyond the top-level
* one (0 for a single-session scenario). Each child rides in a sibling fixture
* `session.<n>.jsonl` (1-based); replay forwards them to `dsh-llm-replay` so
* each child session replays from its own script, and record mode writes the
* harvested child logs back to those files. Defaults to 0.
*/
childSessions?: number
/**
* Whether THIS scenario's fixtures keep the full request-header content (the
* composed system prompt and tool schema list on `request/header` /
* `request/header-delta` events) and compare it verbatim. Exactly one
* scenario per suite pins it; every other scenario stores and compares that
* content as `{{system}}`/`{{tools}}` tokens ({@link scrubRequestHeaders}),
* so a system prompt or tool-schema change shows up as ONE committed-fixture
* diff, not one per scenario. One pin suffices because header composition is
* suite-uniform (parent, spawn child, and fork child all compose the same
* prompt-modulo-cwd and the same tools) — and that premise is ASSERTED, not
* assumed: every non-pinning run's live headers must equal the pinned
* fixture's (normalized), so a session-dependent header (say, a restricted
* subagent toolset) fails loud until it gets its own pinning scenario.
* Defaults to false.
*/
pinsHeader?: boolean
}
/** One suite's inputs: the agent to boot, where its fixtures live, and its scenario table. */
export interface SnapshotSuiteOptions {
/** The agent composition every scenario boots. */
agent: AgentUnderTest
/** Absolute path of the suite's `snapshots/` directory (one subdir per scenario). */
snapshotsDir: string
/** The scenario table; exactly one entry must set `pinsHeader`. */
scenarios: Scenario[]
/**
* `replay` (keyless, the default tier) or `record` (live API; re-records the
* `recorded` scenarios' fixtures and refreshes the vitest goldens under
* `--update`). The caller derives this from `$DSH_SNAPSHOT` — env reading
* stays outside this library.
*/
mode: 'replay' | 'record'
}
/**
* The sibling child-fixture paths for a scenario (`session.1.jsonl` …).
*
* @param dir The scenario's snapshots directory (`<snapshotsDir>/<name>`).
* @param childSessions How many subagent child sessions the scenario records.
* @returns One path per child, 1-based, in fixture order.
*/
export function childFixturePaths(dir: string, childSessions: number): string[] {
return Array.from({ length: childSessions }, (_, i) => join(dir, `session.${i + 1}.jsonl`))
}
/**
* Derive the {@link NormalizeContext} for a `session.jsonl` fixture from its own
* header line (`{ type: 'session', id, cwd }`). A committed fixture carries the
* session id and cwd of the run that harvested it — different from the live
* replay run — so normalizing it against the live run's ctx would leave those
* recorded values unscrubbed. Reading them from the header scrubs the fixture's
* own id/cwd to the same `{{sessionId}}`/`{{cwd}}` tokens the replay output gets.
* An authored fixture whose header is already normalized (`id:'{{sessionId}}'`,
* `cwd:'{{cwd}}'`) yields those tokens as the volatile values, so scrubbing them
* is an idempotent no-op. A header with no `cwd` falls back to a sentinel that
* cannot occur in a log (NOT `''`, which `String.split` would match on every
* character boundary and corrupt the output).
*
* @param fixture The committed `session.jsonl` content.
* @returns The fixture's own volatile values, ready for {@link normalizeSessionLog}.
*/
export function fixtureContext(fixture: string): NormalizeContext {
const firstLine = fixture.split('\n').find(line => line.trim().length > 0) ?? '{}'
const header = JSON.parse(firstLine) as { id?: unknown; cwd?: unknown }
return {
sessionIds: typeof header.id === 'string' ? [header.id] : [],
cwd: typeof header.cwd === 'string' ? header.cwd : '\0no-cwd\0',
}
}
/**
* The `data.header` payload of every `request/header` event in a session
* JSONL, in log order, with the log's volatile values scrubbed first
* ({@link normalizeSessionLog}) so headers harvested from different runs —
* each embedding its own temp cwd in the composed prompt — compare on equal
* footing.
*
* @param rawLog The session `.jsonl` content to extract headers from.
* @param ctx The volatile values of the run that produced it.
* @returns The normalized `data.header` payloads, in log order.
*/
export function normalizedHeaders(rawLog: string, ctx: NormalizeContext): unknown[] {
return normalizeSessionLog(rawLog, ctx)
.split('\n')
.filter(line => line.trim().length > 0)
.map(line => JSON.parse(line) as { type?: unknown; data?: { header?: unknown } })
.filter(record => record.type === 'request/header')
.map(record => record.data?.header)
}
/**
* Count the `request/header-delta` events in a session JSONL.
*
* @param rawLog The session `.jsonl` content.
* @returns How many `request/header-delta` events the log carries.
*/
export function headerDeltaCount(rawLog: string): number {
return rawLog.split('\n')
.filter(line => line.trim().length > 0)
.filter(line => (JSON.parse(line) as { type?: unknown }).type === 'request/header-delta')
.length
}
/**
* Register the suite: one `describe` per scenario (the golden/log compares and
* the header-uniformity guard) plus the fixture guard block (no orphan
* scenario dirs, required files present, exactly one pin, non-pinning fixtures
* header-scrubbed). Must run at vitest collection time — it calls
* `describe`/`it`. Throws immediately if no scenario pins the header (the
* uniformity guard would have nothing to compare against).
*
* @param options The agent, snapshots directory, scenario table, and mode.
*/
export function defineAcpSnapshotSuite(options: SnapshotSuiteOptions): void {
const { agent, snapshotsDir, scenarios, mode } = options
const RECORDING = mode === 'record'
/** The suite's single header-pinning scenario. Guarded here (and by a meta-test) so the pin cannot silently vanish. */
const pinningScenario = scenarios.find(s => s.pinsHeader === true)
if (pinningScenario === undefined) throw new Error('acp-snapshot: no scenario pins the request-header content')
for (const scenario of scenarios) {
describe(`snapshot: ${scenario.name}`, () => {
// In RECORD mode, only re-run the `recorded` (live-API) scenarios; the
// `authored` ones (sidecar-driven errors/cancel) are never re-recorded.
it.skipIf(RECORDING && !scenario.recorded)('matches the goldens', async () => {
const dir = join(snapshotsDir, scenario.name)
const input = JSON.parse(await readFile(join(dir, 'input.json'), 'utf8')) as InputScript
const overrideFile = join(dir, 'replay.override.json')
const workspaceDir = join(dir, 'workspace')
const childSessions = scenario.childSessions ?? 0
const result = await runScenario(input, {
agent,
mode,
fixtureFile: join(dir, 'session.jsonl'),
...existsSync(overrideFile) ? { overrideFile } : {},
// In REPLAY, forward the recorded child fixtures so each subagent session
// replays from its own script. In RECORD they are harvested, not read.
...!RECORDING && childSessions > 0 ? { childFiles: childFixturePaths(dir, childSessions) } : {},
...existsSync(workspaceDir) ? { workspaceDir } : {},
})
// Scrub every volatile id the run produced: the ACP server-issued session
// id plus every harvested log's recorded id (a subagent child id never
// surfaces over ACP, but it appears in the child's own log header). The
// normalizer's UUID catch-all covers any we don't enumerate.
const ctx: NormalizeContext = {
sessionIds: [
...result.sessionId !== undefined ? [result.sessionId] : [],
...result.sessionLogs.map(l => l.id),
],
cwd: result.cwd,
}
// RECORD mode (recorded model scenarios only): persist the freshly-harvested
// logs back to their fixtures — the primary to session.jsonl, each child to
// session.<n>.jsonl in harvest order. `--update` refreshes the Vitest
// goldens but NOT these fixtures, so write them here. A non-pinning
// scenario's fixtures are written header-scrubbed, so a re-record can
// never smuggle the full prompt/schema content back into every fixture.
const scrub = scenario.pinsHeader === true
? (log: string): string => log
: scrubRequestHeaders
if (RECORDING && scenario.recorded && scenario.hasModelTurn) {
expect(result.sessionLogs.length, 'record produced no session log to harvest').toBeGreaterThan(0)
expect(result.sessionLogs.length, `expected ${childSessions + 1} session logs (parent + children)`)
.toBe(childSessions + 1)
await writeFile(join(dir, 'session.jsonl'), scrub((result.sessionLogs[0] as HarvestedLog).content))
for (let i = 1; i < result.sessionLogs.length; i++) {
await writeFile(join(dir, `session.${i}.jsonl`), scrub((result.sessionLogs[i] as HarvestedLog).content))
}
}
await expect(normalizeStdout(result.rawStdout, ctx))
.toMatchFileSnapshot(join(dir, 'stdout.golden.jsonl'))
// A model turn always produces a log worth comparing; a hook scenario can
// produce one without a model turn (a `rejected` turn carrying `hook/*`).
const comparesLog = scenario.comparesLog ?? scenario.hasModelTurn
if (comparesLog) {
// The harvested logs (primary-first) must match their committed fixtures
// 1:1. Each side passes through normalizeSessionLog, scrubbed against ITS
// OWN volatile values — the live run's via `ctx`, the committed fixture's
// via its own header (a committed file cannot share the live run's ids).
// Unless this scenario pins the header, both sides ALSO pass through
// scrubRequestHeaders: the live log carries the real prompt/schemas, the
// fixture carries the `{{system}}`/`{{tools}}` tokens, and the scrub is
// idempotent — so the compare checks the header's presence, position,
// reason, and config, but not its bulk content (pinned once, in the
// `pinsHeader` scenario).
expect(result.sessionLogs.length, 'this scenario must persist a session log').toBe(childSessions + 1)
const fixtureFiles = ['session.jsonl', ...Array.from({ length: childSessions }, (_, i) => `session.${i + 1}.jsonl`)]
for (let i = 0; i < fixtureFiles.length; i++) {
const harvested = scrub((result.sessionLogs[i] as HarvestedLog).content)
const fixture = scrub(await readFile(join(dir, fixtureFiles[i] as string), 'utf8'))
expect(normalizeSessionLog(harvested, ctx), `${fixtureFiles[i]} mismatch`)
.toEqual(normalizeSessionLog(fixture, fixtureContext(fixture)))
}
}
// Header-uniformity guard: the single pin is sound only while every
// session in the suite composes the SAME header and keeps it for the
// whole run. Assert both halves live. (1) Every request/header the run
// produced (parent, spawn child, fork child, initial or resume) must
// equal the pinned fixture's header after each side is normalized
// against its own volatile values. (2) No request/header-delta may
// appear at all — a mid-run header change diverges from the pin by
// construction, and its content would be invisible under the scrub. If
// either fails, either the header changed (update the pin: re-record or
// hand-edit the pinning scenario's fixture) or composition became
// session-dependent by design (give the divergent shape its own
// pinning scenario).
if (scenario.pinsHeader !== true) {
const pinnedFixture = await readFile(join(snapshotsDir, pinningScenario.name, 'session.jsonl'), 'utf8')
const pinned = normalizedHeaders(pinnedFixture, fixtureContext(pinnedFixture))
expect(pinned.length, `the pinning fixture (${pinningScenario.name}) must carry exactly one request/header`)
.toBe(1)
for (const log of result.sessionLogs) {
expect(headerDeltaCount(log.content), `session ${log.id}: a request/header-delta in a non-pinning scenario`)
.toBe(0)
const headers = normalizedHeaders(log.content, ctx)
for (const [k, header] of headers.entries()) {
expect(header, `session ${log.id}: request/header #${k + 1} diverged from the pinned (${pinningScenario.name}) header`)
.toEqual(pinned[0])
}
}
}
})
})
}
describe('snapshot fixtures', () => {
it('every scenario directory is registered (no orphans)', async () => {
// toMatchFileSnapshot does not prune orphaned golden/fixture files, so a
// renamed/removed scenario could leave a stale dir that nothing exercises.
// Fail loud on any snapshots/<dir> not present in the scenario table.
const entries = await readdir(snapshotsDir, { withFileTypes: true })
const onDisk = entries.filter(e => e.isDirectory()).map(e => e.name).sort()
const registered = scenarios.map(s => s.name).sort()
expect(onDisk).toEqual(registered)
})
it('every registered scenario has its required fixture files', () => {
// Every scenario has an input script and an stdout golden. EVERY scenario
// also needs `session.jsonl`: the suite boots `llm-replay` with that path
// as the replay source for ALL scenarios (the factory passes
// `fixtureFile: <dir>/session.jsonl` unconditionally), and `loadReplayScript`
// throws "fixture not found" when it is absent and no override replaces it.
// A no-model scenario ships a header-only `session.jsonl` (it derives to an
// empty script — no model call is made); a model scenario's fixture also
// doubles as the expected-log artifact the run is diffed against. The
// `replay.override.json` sidecar is matched BOTH ways against the table's
// `overridden` flag: required when set, forbidden when not — the harness
// forwards the file purely on existence, so an unregistered stray sidecar
// would silently replace the derived script.
for (const { name, overridden, childSessions } of scenarios) {
const dir = join(snapshotsDir, name)
expect(existsSync(join(dir, 'input.json')), `${name}/input.json`).toBe(true)
expect(existsSync(join(dir, 'stdout.golden.jsonl')), `${name}/stdout.golden.jsonl`).toBe(true)
expect(existsSync(join(dir, 'session.jsonl')), `${name}/session.jsonl`).toBe(true)
expect(existsSync(join(dir, 'replay.override.json')), `${name}/replay.override.json presence must match \`overridden\``)
.toBe(overridden === true)
// A nested-agent scenario ships one child fixture per recorded subagent
// session (`session.1.jsonl` …), the replay source for that child session.
for (const childFixture of childFixturePaths(dir, childSessions ?? 0)) {
expect(existsSync(childFixture), childFixture).toBe(true)
}
}
})
it('exactly one scenario pins the request-header content', () => {
// Zero pins would drop the prompt/schema surface from the suite entirely;
// two would split it. One pin per suite is the design (pinned-header RFC);
// WHICH scenario pins is the scenario table's reviewable choice.
expect(scenarios.filter(s => s.pinsHeader === true).map(s => s.name)).toEqual([pinningScenario.name])
})
it('committed fixtures carry request-header content ONLY in the pinning scenario', async () => {
// The whole point of the pin: a system-prompt or tool-schema change must
// churn exactly one committed line. A non-pinning fixture that carries the
// full header (a hand-recorded file, or a header line hand-edited out of
// its canonical JSON form) silently reopens the suite-wide churn, so fail
// loud here: every non-pinning session*.jsonl must be a fixed point of
// scrubRequestHeaders (apply the scrub to fix a violation), and the
// pinning scenario's fixtures must NOT be (their content IS the pin).
for (const scenario of scenarios) {
const dir = join(snapshotsDir, scenario.name)
const files = [
'session.jsonl',
...Array.from({ length: scenario.childSessions ?? 0 }, (_, i) => `session.${i + 1}.jsonl`),
]
for (const file of files) {
const fixture = await readFile(join(dir, file), 'utf8')
if (scenario.pinsHeader === true) {
expect(scrubRequestHeaders(fixture), `${scenario.name}/${file} must PIN the full header content`)
.not.toEqual(fixture)
} else {
expect(scrubRequestHeaders(fixture), `${scenario.name}/${file} carries unscrubbed header content`)
.toEqual(fixture)
}
}
}
})
})
}