Mutate with custom updater when no useSWR seems to have wrong state

Bug report

Description / Observed Behavior

Simple case is:

• a user action that will trigger a mutate on a key with a custom updater
• after this action is done mount a component (or in a next js app push to router) that will use this key

-> the data that I see is not correct.

Expected Behavior

Expected behavior are:

• if mutate is call and then a first useSWR is done on the same key, we should expect correct data -> request is correctly done, but data does not seems to be use / drop

Repo Steps / Code Example

if you run this example: click on the button you will see that request is done -> but only the mutate data is use.

https://codesandbox.io/s/clever-knuth-2z40o?file=/src/App.js:1128-1161

Additional Context

0.3.9

[AyWa]

No this is not what I want to see. Sorry if I didnt explain well. The behavior is:

• I do not want to display the 2 component at the same time (because they could be different page) - > So the example given replicate that
• I do not want to set the last argument to false (because I want to revalidate)

What I expect is:

• user click button
• mutate the key - > update data
• mount a component that will use the key
• so show fake
• after api answers it should be updated

Does the flow is clear now? Let me know If my explanation is correct

[AyWa]

Thanks a lot for the fast investigation and fix !! You Rock 🥳