View emitting only one field of a document results in multiple rows with different values

From time to time, views get "corrupted" and multiple rows with different values are emitted for a single document.

For example, when I tried to reproduce the bug, I created a bucket and populated it with 1000000 documents containing one single field - "random" - initialised to a random value in the range 0-9. Then I just used the following view to get all the documents for a given value of "random", assigned a new random value to each document and saved them.

function (doc, meta)

The problem is, after a while, the view starts returning things like that :

"id":"2ae8bdf2-0de1-4345-880d-5fce39286099","key":0,"value":null},
[...]
"id":"2ae8bdf2-0de1-4345-880d-5fce39286099","key":1,"value":null},

This problem is observed even when you request the view with stale=false.