Implementation:DevExpress Testcafe TestRunTracker

Knowledge Sources	DevExpress_Testcafe
Domains	Async_Context, Test_Execution
Last Updated	2026-02-12 12:00 GMT

Overview

Concrete utility that tracks the association between asynchronous execution contexts and their corresponding test runs, enabling TestCafe to resolve which test run is active when user code calls API methods.

Description

TestRunTracker uses Node.js async_hooks to track the relationship between async operations and test runs. When a test function executes, the tracker registers the current async context ID with the test run. Any subsequent async operations (callbacks, promises, timers) inherit this context. This allows methods like t.click() to automatically find the correct test run even when called from deeply nested async callbacks without explicit parameter passing.

Usage

This is a core infrastructure component that enables the t proxy to work. It runs automatically and is not called directly by test authors.

Code Reference

Source Location

• Repository: DevExpress_Testcafe
• File: src/api/test-run-tracker.ts
• Lines: 1-126

Signature

class TestRunTracker {
    private _contextToTestRunMap: Map<number, TestRun>;
    private _hook: AsyncHook;

    public enabled: boolean;

    public addTrackingMarkerToFunction (testRunId: string, fn: Function): Function;
    public resolveContextTestRun (): TestRun | null;
    public getContextTestRunId (): string | null;
    public ensureEnabled (): void;
}

export default new TestRunTracker();

Import

import testRunTracker from '../api/test-run-tracker';

I/O Contract

Inputs

Name	Type	Required	Description
testRunId	string	Yes	ID of the test run to associate with the async context
fn	Function	Yes	Function to mark with the test run context

Outputs

Name	Type	Description
resolveContextTestRun()	TestRun or null	The test run associated with the current async context
Wrapped function	Function	Function with injected test run tracking

Usage Examples

import testRunTracker from '../api/test-run-tracker';

// Internal: mark a test function with its test run context
const wrappedFn = testRunTracker.addTrackingMarkerToFunction(testRunId, userTestFn);

// Internal: resolve the current test run from any async context
const testRun = testRunTracker.resolveContextTestRun();
if (testRun)
    testRun.executeCommand(command);

Related Pages

• Environment:DevExpress_Testcafe_Node_Runtime