Scrubbers.md

Scrubbers

Contents

• Introduction
• Interface
• How to use Scrubbers
• Scrubber concepts
• See also

Introduction

If you are having trouble getting tests running reproducibly, you might need to use a "scrubber" to convert the non-deterministic text to something stable.

Interface

Fundamentally, a scrubber is function that takes a string and returns a string. You can create ones by passing in a function or a lambda. We also have some pre-made ones for your convenience.

How to use Scrubbers

You can scrub text manually, before passing it in to Approvals::verify(), but the preferred method is to include a Scrubber as an option.

Approvals::verify(input, Options().withScrubber(scrubber));

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Scrubber concepts

There are several patterns that are commonly used when scrubbing:

• Replace troublesome text
• Replace troublesome text, tracking duplicates
• Combining scrubbers
• Deleting troublesome lines

See also

• How to Scrub Non-Deterministic Output

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