beforeRouteUpdate fire twice when query contain empty array []

[newbeea]

Version

2.7.0

Reproduction link

http://jsfiddle.net/a9v43732/

Steps to reproduce

go to foo
then click 'beforeRouteUpdate' button
beforeRouteUpdate fire twice when query contain empty array []

eg.
this.$router.push({query: {a: Math.random(), b: []}})
beforeRouteUpdate fire twice

this.$router.push({query: {a: Math.random(), b: [1]}})
beforeRouteUpdate fire once

What is expected?

this.$router.push({query: {a: Math.random(), b: []}})
beforeRouteUpdate shoud fire once

What is actually happening?

this.$router.push({query: {a: Math.random(), b: []}})
beforeRouteUpdate fire twice

[posva]

This is probably related to #1722
The route object gets normalized and the array is stripped off, making the route change fire twice.
As a temporary workaround, you can remove empty arrays from query objects

[ghost]

@posva This also happens without sending any route parameters. Should i open new issue with example?

[posva]

if there isn't an open issue about it and you provide a boiled down repro, yes please!