(Windows) First test fails with "error: Failed to snapshot value"

[pragmatta]

I don't know what happened but for some reason the first test started to always fail with "error: Failed to snapshot value: VALUE". If I comment out that test, the next will fail. If I add a dummy test like below in the beginning that will fail.
test("dummy", () => { expect(true).toMatchSnapshot() })

All tests after that succeed. Even the failing test will succeed later (they are iterated over different parameters). Running with --update-snapshots will succeed but fails again after this. Deleting snapshots or upgrading to 1.1.4 did not help.

Probably very hard to replicate, something in this setup. Any hints appreciated.

[pragmatta]

Happened to figure this one out, the snapshotting can generate a snapshot file that it can't parse. While my tests where successful, it was actually failing read anything from the snapshot and basically treated the snapshot as empty and was writing the snapshots in the file over and over again.

What creates a corrupted snapshot is \x in data that gets treated as a hex escape sequence. For example this test (with valid CSV data)

test("dummy", () => {
        expect("\"x\\x\"").toMatchSnapshot()
})

generates snapshot

exports[`dummy 1`] = `""x\x""`;

Which is invalid Javascript (I assume the file gets evaluated).