Error computed side-effects error when accessing getter

[Josiah Witt]

When attempting to write a getter which consolidates a nested object, signals throws an error.

Reproduction:

const state = deepSignal({
  x: {
    a: 1,
    b: 2,
  },
  get y() {
    return Object.values((state.x as RevertDeepSignal<typeof state.x>) ?? {});
  },
});

console.log(state.y);

Error:

Error: Computed cannot have side-effects
      at mutationDetected (node_modules/.pnpm/@preact+signals-core@1.3.1/node_modules/@preact/signals-core/src/index.ts:5:8)
      at value (node_modules/.pnpm/@preact+signals-core@1.3.1/node_modules/@preact/signals-core/src/index.ts:314:4)
      at Object.values [as ownKeys] (node_modules/.pnpm/deepsignal@1.3.3_react@18.2.0/node_modules/deepsignal/core/src/index.ts:120:29)
      at Function.values (<anonymous>)

[Luis Herranz]

Interesting. It should be easy to fix. I just need to find another way to trick the minifier into thinking that the access to the .value shouldn't be removed in this line.

Thanks for the report!

[Luis Herranz]

PR with the fix:

• #33

[Josiah Witt]

Thanks for taking a look at this so quickly! I'll try it out once it's released.

[Luis Herranz]

Released as deepsignal@1.3.4. Please let me know if this fixed the issue 🙂

[Josiah Witt]

@luisherranz I'm getting back from some vacation earlier this week. Hoping I'll be able to try this out next week and I'll let you know if it resolves the issue I was seeing.

[Josiah Witt]

@luisherranz I can confirm that I'm able to run the above code now without it crashing 👍 my apologies for the delay

[Luis Herranz]

Cool, thanks 🙂