If you're using Playwright for end-to-end testing and have come across the dreaded “no tests found” error, you’re not alone. It’s an error that catches many of us by surprise, especially when our tests look perfectly fine. 

The message, “Make sure that arguments are regular expressions matching test files,” typically indicates that Playwright couldn’t locate your test files based on the parameters provided. 

Sometimes, it’s as simple as missing quotes around your regex pattern, while other times, it’s a configuration setting that needs tweaking. Let me walk you through some practical solutions, drawing from my personal experience and insights from other Playwright users.

Understanding the Error

When Playwright displays the “no tests found” error, it’s telling us that it couldn’t find any test files that match the specified criteria or regex pattern. 

This message is usually accompanied by a suggestion to ensure that the arguments you’ve used are correct and formatted properly.

In my experience, this error often pops up in these scenarios:

  • Improper Regular Expression: Symbols like $ or * can interfere if not handled correctly.
  • Test File Location: Playwright can only recognize files if they’re in the expected folder.
  • Incorrect Configuration: Misalignment in config files or arguments can prevent Playwright from detecting tests.

Solution 1: Adjust Your Regex Pattern

One of the most common causes of this issue is a problematic regular expression in your Playwright test command. If you’re using special characters like $ or *, ensure they are escaped properly. For instance:

npx playwright test --grep 'yourPattern\$'

If you’re calling the test command with a specific pattern, make sure that pattern actually matches the file names. In cases like this, it helps to wrap your pattern in quotes:

npx playwright test "myTests*"

Solution 2: Verify Test File Location and Structure

Playwright has specific expectations regarding where test files should be located. By default, it looks for test files in the tests folder. If your files are located elsewhere, let Playwright know by configuring your playwright.config.js file accordingly:

module.exports = {
        testDir: './yourTestFolder',
        // Other configurations
    };
    

Also, ensure your test files follow the naming convention. For example, Playwright will look for .spec.ts or .test.ts files by default. If your files have different extensions or suffixes, update the configuration to reflect this.

Solution 3: Check testMatch in playwright.config.js

A missing or mismatched testMatch setting in your playwright.config.js can easily lead to the “no tests found” error. The testMatch field specifies which files Playwright should recognize as test files.

module.exports = {
        testMatch: '**/*.spec.js', // Modify based on your file naming pattern
    };
    

If your test files use different naming conventions or are located in various subdirectories, customize the testMatch to fit your file structure.

Solution 4: Ensure Correct Test Command

When running Playwright tests from the command line, make sure you’re using the correct command syntax. A common issue is forgetting to include the npx prefix or omitting other necessary arguments. Here’s a reliable format to follow:

npx playwright test

If you need to run a specific test or suite, specify it directly:

npx playwright test myTests/testFile.spec.js

Solution 5: Verify Test Code Structure

Ensure that your tests are written correctly and follow Playwright’s syntax requirements. Each test should be encapsulated in a describe or test block. Here’s a sample structure:

const { test, expect } = require('@playwright/test');

    test.describe('My Test Suite', () => {
        test('Should pass the test case', async ({ page }) => {
            await page.goto('https://example.com');
            await expect(page).toHaveTitle(/Example/);
        });
    });
    

If your code structure doesn’t align with Playwright’s expectations, it might skip over files that appear empty or malformed.

Solution 6: Use Verbose Logging for Debugging

For persistent issues, try enabling verbose logging. This will show you detailed logs of what Playwright is attempting to do and where it might be going wrong:

DEBUG=pw:api npx playwright test

This command will output detailed information to help you diagnose the issue and pinpoint why Playwright isn’t locating your tests.

Solution 7: Test File Permissions

In some cases, file permissions can interfere with test detection, especially if you’re working in a shared development environment or have recently transferred files. Make sure your test files are accessible by Playwright:

chmod +r yourTestFolder/*

The “no tests found” error in Playwright is often straightforward to solve but can sometimes hide deeper configuration or syntax issues. 

By following the solutions above, you’ll likely identify the source of the issue and get your tests running smoothly. Here’s a quick checklist of key solutions to try:

  • Adjust your regex pattern, especially if using special characters.
  • Verify the location and naming conventions of test files.
  • Configure testMatch accurately in playwright.config.js.
  • Use the correct command syntax in the terminal.
  • Double-check your test structure to ensure it meets Playwright’s standards.
  • Enable verbose logging for detailed troubleshooting.
  • Confirm file permissions if working in a shared environment.