Data deep merge not working as expected - any way to achieve it?

[andreimoment]

I expect that a data file in the page's folder will override the values defined in a data file in the _data folder.

Given the files described further below, pre #{JSON.stringify(data)} in the page should return {"foo":{"a":1,"b":200}} but instead I get {"foo":{"b":200}} - basically if src/pages/foo/foo.yaml exists, nothing from src/ _data/data/foo.yaml loads.

What I am hoping to achieve is a deep merge of data variables from both files so I can define defaults in _data and replace only some values in the page data file - or leave them as the default if preferred.

How can I achieve something like that?

Here's an example:

//src/_data/data/foo.yaml  
a: 1

//src/pages/foo/foo.yaml
data:
  foo:
    b: 200

//src/pages/foo/foo.pug
pre #{JSON.stringify(data)}

//rendered page content:
{"foo":{"b":200}}

//desired page content:
{"foo":{"a": 1, "b":200}}

I cannot get both yaml files' data to load at the same time. Isn't this something that would work with eleventyConfig.setDataDeepMerge(true)?

I am using 11ty version 0.12.1

Even if I comment out the contents of pages/foo/foo.yaml, the _data/data/foo.yaml does not load. If I delete the pages/foo/foo.yaml, then the _data/data/foo.yaml does load.

This is not helpful, because I'm hoping to define default datasets in the _data/data folder and then override them on a page basis, like this:

//pages/foo.pug
+bio-card(data)

//pages/foo.pug
data:
  bio_card:
    name: John Smith
    email: [email protected]

// which would override the default for this component
// _data/data/bio_card.yaml
name: Sample Name
email: [email protected]