ngx-testbox

name	ngx-testbox
description	Angular integration tests, ngx-testbox, runTasksUntilStable, runTasksUntilStableAsync, DebugElementHarness, testboxTestId. Use when creating, fixing, or reviewing Angular tests that use ngx-testbox or should use its black-box testing patterns.
license	MIT
compatibility	ngx-testbox: 2.0.0

ngx-testbox

Use this skill whenever you create, review, debug, or refactor Angular integration tests that use ngx-testbox.

This skill is part of the ngx-testbox library itself and is intended to ship with the library source.

Before working, load the focused companion docs that match the task:

• Creating, editing, or reviewing a test: read quick-reference.md and testing.md first.
• Using async/await, zoneless testing, Promise response getters, or fake timers in async mode: read async-approach.md.
• Using fakeAsync, tick(), or sync stabilization in an existing zone-based suite: read sync-fakeasync-approach.md.
• Choosing between modes, or debugging timeout/cancellation/timing behavior that applies to both: read concepts.md.
• Looking for a proven implementation pattern or starter skeleton: read examples.md.

Common gotchas to keep in mind before editing tests:

• runTasksUntilStable and runTasksUntilStableAsync call fixture.detectChanges() internally, so finish stubbing, inputs, and harness setup before the first stabilization call.
• Do not mix ngx-testbox stabilization with direct HttpTestingController.expectOne(...) flows in the same test unless you are deliberately doing low-level debugging.
• String URL matchers use .includes(...), so broad paths can match more than intended.
• delay and timeline cannot be used together on the same instruction.

Companion docs:

• quick-reference.md: condensed rules for fast implementation
• concepts.md: purpose, decision rules, supported APIs, strictness, and errors
• testing.md: setup patterns, harness usage, workflow, assertions, and troubleshooting
• async-approach.md: async stabilization workflow, timing, and examples
• sync-fakeasync-approach.md: fakeAsync stabilization workflow, timing, and examples
• examples.md: cross-cutting patterns and starter snippets

Recommended reading order when you need broad context:

1. quick-reference.md
2. testing.md
3. concepts.md
4. examples.md

Important: both stabilization APIs are supported parts of the library.

• runTasksUntilStableAsync is the preferred default for new tests.
• runTasksUntilStable remains an eligible, supported API for fakeAsync and existing zone-based suites.

Choose based on the test environment and current suite patterns, not on the assumption that sync support is obsolete.