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---
16 out of ~150 recently added sprout fixtures have exceptions that reflect
easy-to-miss mistakes in the fixture input, like forgetting to import
`useState`.
This PR adds snapshot files for sprout to prevent these mistakes (or catch them
at diff review time). This describes what it implements, but happy to take other
suggestions as well!
1. One sprout snapshot file for each input.
This significantly increases the number of files we have, but makes it clear
what the fixture is testing. I was hoping to expand on these snapshots to record
the result of multiple re-renders, or mounts (with different parameters), but
the tradeoff is that adding / changing fixtures will now require running `yarn
sprout --mode update`.
Some alternatives I've considered:
- Only record snapshots for fixtures that error (`result.kind == "exception"`).
This change would be pretty easy. This doesn't help sanity check sprout results
for general mistakes though ("am I testing what I want to test?)
- Warn loudly for fixtures that error -- seems like these are easy to ignore,
but.. worth it for the convenience?
- Some github action that runs and comments on your PR with sprout fixture
changes; i.e. never manually update sprout files?
2. Sprout and snap share a common snapshot file, with some parsing hackery.
Previously, the implementation added new files to a separate sprout snapshot
directory, assuming that devs don't need to read these often.
After feedback from @josephsavona, I updated to have snap and sprout write to
the same file for ease of reviewing / debugging (to be able to see the input /
output side by side).
- `snap --mode update` will update snap's part of the file.
- `sprout --mode update` will update sprout's part
- `snap` and `sprout` will both compare oldSnapshot (read from the file) with
`newSnapshot = merge(oldSnapshot, newData)` to determine if a test pass.
3. Some hacks 😅 Absolute paths to project directory (e.g. stack traces) are
replaced with `<project_root>` in a mocked `console.log`