Reporter overhaul (3/6): shadow structured emission

[Sean Larkin (TheLarkInn)]

📚 Reporter Overhaul PR stack (merge bottom-up)

#	PR	Phase	Base
1	#5865	Contracts & baselines (package)	main
2	#5866	Bootstrap & compatibility	#5865
3	#5867	Shadow structured emission	#5866
4	#5868	Opt-in reporters	#5867
5	#5869	Heft protocol track	#5868
6	#5870	Perf budgets & default flip	#5869

Each PR's diff is scoped to its phase; review independently, merge from #5865 upward.

👉 This is PR 3 of 6.

Phase 3 — Shadow structured emission (RFC §8.1)

First-party lifecycle and diagnostic events are emitted without changing visible output, and telemetry/exit-code parity is validated.

What's included

• RushSession event sink + scoped producers exposed to actions and plugins (plugins cannot inspect modes/destinations/thresholds).
• Shadow lifecycle emission — structured lifecycle + diagnostic events run alongside the legacy renderer with no output change.
• Telemetry projection subscriber — allowlist + beforeLog adapter.
• Reporter-independent exit codes — command success/exit semantics preserved regardless of the active reporter.

Validation

• rush build --to @rushstack/reporter ✅ rush test --only @rushstack/reporter ✅ (adds Session, Lifecycle, Telemetry, ExitStatus suites)
• All exports @beta.

Scope note

Standalone package; not yet wired into the live CLI. Independently releasable/revertible per RFC §8.1.

[Copilot]

Pull request overview

Adds phase-3 shadow structured reporting to the standalone Rush reporter package without changing visible CLI output.

Changes:

• Adds scoped session, plugin, and lifecycle reporting APIs.
• Adds telemetry projection and legacy hook adaptation.
• Adds reporter-independent exit-status helpers and validation suites.

Reviewed changes

Copilot reviewed 26 out of 26 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
research/progress.txt	Records phase-3 implementation progress.
research/feature-list.json	Marks features 11–14 complete.
libraries/reporter/src/test/Telemetry.test.ts	Tests telemetry projection and privacy.
libraries/reporter/src/test/Session.test.ts	Tests scoped session and plugin APIs.
libraries/reporter/src/test/Lifecycle.test.ts	Tests shadow lifecycle parity.
libraries/reporter/src/test/ExitStatus.test.ts	Tests exit-status and JSON controls.
libraries/reporter/src/telemetry/TelemetrySubscriber.ts	Aggregates telemetry from events.
libraries/reporter/src/telemetry/TelemetryAggregate.ts	Defines the telemetry allowlist.
libraries/reporter/src/telemetry/BeforeLogAdapter.ts	Adapts legacy telemetry hooks.
libraries/reporter/src/session/ScopedReporterFactory.ts	Creates scoped event producers.
libraries/reporter/src/session/ScopedLogger.ts	Adds a presentation-free logger.
libraries/reporter/src/session/RushSessionReporting.ts	Exposes session reporting contexts.
libraries/reporter/src/session/PluginApi.ts	Adds plugin compatibility contracts.
libraries/reporter/src/lifecycle/ShadowParity.ts	Derives shadow result parity.
libraries/reporter/src/lifecycle/LifecycleEvents.ts	Defines lifecycle payloads and statuses.
libraries/reporter/src/lifecycle/LifecycleEmitter.ts	Emits structured lifecycle events.
libraries/reporter/src/index.ts	Exports the new APIs.
libraries/reporter/src/exit/ExitStatus.ts	Resolves reporter-independent exit status.
libraries/reporter/src/exit/CommandJson.ts	Separates command and reporter JSON flags.
libraries/reporter/src/diagnostics/templates/configuration.ts	Adds the plugin incompatibility message.
libraries/reporter/src/diagnostics/RushDiagnosticCodeRegistry.ts	Registers the plugin diagnostic.
common/reviews/api/rush-reporter.api.md	Updates the public API report.
common/changes/@rushstack/rush-reporter/docs-rush-reporter-overhaul-spec_2026-07-15-00-35-03.json	Records exit-status APIs.
common/changes/@rushstack/rush-reporter/docs-rush-reporter-overhaul-spec_2026-07-15-00-30-21.json	Records telemetry APIs.
common/changes/@rushstack/rush-reporter/docs-rush-reporter-overhaul-spec_2026-07-15-00-24-15.json	Records lifecycle APIs.
common/changes/@rushstack/rush-reporter/docs-rush-reporter-overhaul-spec_2026-07-15-00-18-26.json	Records session and plugin APIs.

Suppressed comments (2)

libraries/reporter/src/telemetry/TelemetrySubscriber.ts:104

• This counts status-transition events rather than operations by final status. A normal operation that transitions ready → executing → success contributes to three buckets, whereas the frozen legacy telemetry counts each operation once from its final operationResult.status (PhasedScriptAction.ts:1100-1145). Track the latest status by operationId and derive the counts from that map when building the aggregate.

      case 'operationStatusChanged': {
        const status: string = (event.payload as { status: string }).status;
        this._operationStatusCounts[status] = (this._operationStatusCounts[status] ?? 0) + 1;
        break;

libraries/reporter/src/lifecycle/ShadowParity.ts:93

• Like the telemetry subscriber, this summary counts every status transition rather than each operation's final status. That inflates parity counts for any operation that emits normal intermediate states and cannot match the legacy final-result summary. Retain the latest status per operationId, then count the final map values.

  for (const event of events) {
    if (event.type === 'operationStatusChanged') {
      const payload: IOperationStatusChangedPayload = event.payload as IOperationStatusChangedPayload;
      operationCounts[payload.status] = (operationCounts[payload.status] ?? 0) + 1;

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[Mo Jazayeri (mojaza)]

Overall, LGTM with a minor comment.