Version

3.2.22

Reproduction link

v3.vuejs.org

Steps to reproduce

Try watching a nested property using the syntax "a.b". See for instance the example from the documentation, starting on line 26 (or 27?, the numbers don't align with the code).

'c.d': function (val, oldVal) {
  // do something
},

What is expected?

Either the watcher should be called, or the lines 26-30 should be removed from the example in the documentation. According to #671, the implementation behavior is correct.

What is actually happening?

The watcher function will not be called, but the documentation looks like it should work.

I think this functionality is really useful, and would rather see it in Vue 3 as well.

Sorry, I relied on old info (#671) and had another issue in my code.