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answer: direct
beat: dev-practices
source: 1 article · updated: September 1, 2026
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Why is a large-scale test framework migration usually so slow to do by hand?

Two testing frameworks like Enzyme and React Testing Library operate at different levels of abstraction — one inspects component internals, the other tests from a user's perspective — so tests can't be translated line-for-line. Every file needs structural understanding, not mechanical find-and-replace, which is exactly the kind of judgment-heavy, repetitive work that eats engineering-years at scale.

Answered in

How to Migrate Thousands of Legacy Test Files With LLMs, Not Rewrites

A step-based pipeline, retry loops instead of perfect prompts, and rich context injection turn a year-long manual migration into a six-week automated one.

Crashtech Editorial September 1, 2026 Development Best Practices

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