Imported array is flattened in the parent array rather than replacing $import node

[tom-tan]

The spec says:

Once loaded and processed, the $import node is replaced in the document structure by the object or array yielded from the import operation.

However, when the loaded object is an array, it is flattened in the parent array rather than replacing $import node.

How to reproduce

parent.json:

{
    "form": [
        "bar",
        {
            "$import": "import.json"
        }
    ]
}

import.json

["hello", "world"]

$ schema-salad-tool --print-pre parent.json

Expected behavior

The $import node is replaced by an array as follows:

$ schema-salad-tool --print-pre parent.json
{
    "form": [
        "bar",
        [
            "hello",
            "world"
        ]
    ],
    "name": "file:///workspaces/schema_salad/parent.json"
}

Actual behavior

Elements in the array in the $imported document are flattened in the parent array as follows:

$ schema-salad-tool --print-pre parent.json
{
    "form": [
        "bar",
        "hello",
        "world"
    ],
    "name": "file:///workspaces/schema_salad/parent.json"
}

Versions

$ schema-salad-tool --version
/home/vscode/.local/bin/schema-salad-tool Current version: 8.2.20211116214159

Note that this undocumented behavior is already used in metaschema.

[tetron]

You are right. This should be documented. Possibly we could introduce a new operation that has explicit insert/merge behavior and make import behave consistently.