batch() does not work with multiple Array.splice operations

[flunderpero]

Describe the bug

Using <For> on an array and updating that array inside a batch() throws errors indicating that <For> tries to render an undefined item. It looks a bit like #960 where it creates "holes" in the array.

Applying multiple splice on the same array without batch works fine.

Your Example Website or App

https://playground.solidjs.com/?version=1.4.1#NobwRAdghgtgpmAXGGUCWEwBowBcCeADgsrgM4Ae2YZA9gK4BOAxiWGjIbY7gAQi9GcCABM4jXgF9eAM0a0YvADo1aAGzQiAtACsyAegDucAEYqA3EogcuPfrwBi3LLxNRczABZTZ8xSroNbT0LKxtuPgFmIXc4AFl6XCgTNTgfOQVlVSDdAzJcbjhQiCtmWgh83gBJXDhFAF5eAApCeUIyRHtNToh6GBNxc15ailxO-MYMAHMpAEpeeoA+fiteQThcJgheAB4NXhF3KC1NepBW2naAOk1JRfO2siuR3Ekd-Q1FywhJb6sZegQZi4NDlXgAQUIhCa8xAq14ZQqfHysQWCJitQSSRScCacO2awOR06+MJhK8aDUIiEEE6wHhZLWAm6vAAjC4Xp0VKyVFIsAzGcyRJ0AEwcuCjLlgEW8yT8gmMrrC3gAZnFkqyKtl8sVAF0dYS5fDJLM-gSAUCQWCyIYoNDYQK3B5PE0YQtlqTGYjKjBaAA3NKNFG1K6HJJXClUmlXMiEDSsJrstmmgVrYNwUNHCOeSnU4QxuNoBMABhcpd4V0rvoDKYVc2+a0kVnhQk2jG2TQFOxEaD9i1Tu3oan7dbJOycEjgUC8Z3TmfDkbzPxHirJICaaFqMHmS12NTqvFOIE3dRuImkLzOJ5gzwlr14+kWTdHhPeE5XjPeQ4-Y5MiQK2zlMw8YANazrahB3AAyhB7x-rgAE-rs+g9n28K1s+Vg0mIjCujuyw7JChAPosLgiLQzB9MIuBXFMGwAKKpPAEC4AAQvgVQiJ2YB2oQKizAAhLWYCSLqQA

Steps to Reproduce the Bug or Issue

See the Codepen. If you remove the batch call on line 21 then everything works fine.

Expected behavior

Multiple splice calls on the same array should work inside a batch.

Screenshots or Videos

No response

Platform

• macOS
• Chrome
• 100

Additional context

No response

[ryansolid]

This is actually a tricky issue and oversight on my part. The correct behavior and desired behavior are miles away from each other and I think it is time to address it. There is a bug here. There shouldn't be holes. But technically your first splice should get ignored the way batching works in Solid. You should end up with a 4 item array. But that also makes no sense for people. So its time to address what our batching behavior should look like.