A casual note on the disadvantages of Jest snapshot testing and why you might want to avoid it.

Disadvantages

Tests Become Fragile

Snapshot testing makes it easy to detect UI changes, but even changes that are not relevant to the test (e.g., renaming a class name without altering the appearance) can cause the test to fail.

Unclear Assertion Expectations

Snapshot testing uses the toMatchSnapshot() assertion, but when a test fails, it can be difficult to understand the expected behavior. You have to judge based on the snapshot diff, but the assertion is often too concise to determine the correct state.

Delayed Test Writing

Snapshot tests tend to fail repeatedly unless the implementation is complete, making it necessary to wait until the implementation is finished before writing the tests.

References

There aren't many Japanese articles discussing the drawbacks of Jest, but the following article is well-organized and highly informative:

• azukiazusa.dev - スナップショットテストとアサーションテスト