Support simple dynamic expressions on DOLT_DIFF

I would like to look at the commit history of two branches, and then see if the same airspace (table row) was modified in one of the unique commits on branch X and one of the unique commits on branch Y. The idea is to see if someone has been working on the same entity on these two branches. I wrote the following query for this:

SELECT id, entity_type

FROM (
    -- Modified on Y directly.
    SELECT DISTINCT(COALESCE(to_id, from_id)) AS id, 'airspace' AS entity_type, 'y' AS change_origin

    FROM DOLT_DIFF('INT...branch-x', 'airspaces')

    UNION

    -- Modified on X directly.
    SELECT DISTINCT(COALESCE(to_id, from_id)) AS id, 'airspace' AS entity_type, 'x' AS change_origin

    FROM DOLT_DIFF('branch-x...INT', 'airspaces')
) modified_entity

GROUP BY id, entity_type

HAVING COUNT(change_origin) > 1

This query succeeds as expected. I would now like to expand this query to run for a dynamic set of branches on just one side: branch-x will always be fixed, but I would like to query the dolt_branches table and select a few branches where I can then do this same comparison with respect to branch-x.

In SQL terms this could look like this:

SELECT
    branch.name,
    (
        SELECT COUNT(CONCAT(id, entity_type))
        
        FROM (
            -- Modified on Y directly.
            SELECT DISTINCT(COALESCE(to_id, from_id)) AS id, 'airspace' AS entity_type, 'y' AS change_origin
        
            FROM DOLT_DIFF(CONCAT(branch.name, '...branch-x'), 'airblocks')
        
            UNION
        
            -- Modified on X directly.
            SELECT DISTINCT(COALESCE(to_id, from_id)) AS id, 'airspace' AS entity_type, 'x' AS change_origin
        
            FROM DOLT_DIFF(CONCAT('branch-x...', branch.name), 'airblocks')
        ) modified_entity
        
        GROUP BY id, entity_type
        
        HAVING COUNT(change_origin) > 1
    ) AS warning_count

FROM dolt_branches branch

WHERE branch.name != 'branch-x'

However, this yields the following error:

Invalid argument to dolt_diff: concat(branch.name,'...branch-x') – only literal values supported 

I need a three-dot diff in this case, but using the simplified syntax DOLT_DIFF(branch.name, 'branch-x', 'airspaces') for the two-dot diff yields another error:

unable to find field with index 1 in row of 0 columns. This is a bug. Please file an issue here: https://github.com/dolthub/dolt/issues 

Is this something that can be supported, even if in a simple form? I've explored some other avenues:

• Scan the dolt_diff_* tables instead, but those depend on the active checked out branch and won't let me easily identify common commits.
• Fetch branches up front, loop over them, and perform multiple queries, each with fixed values. This will work, but I would later on like to add a filter on branches WHERE warning_count > 0 and paginate with LIMIT, which becomes somewhat painful as I will just need to keep querying until I meet the expected page sizes (as I don't know which branches will be filtered out or not) and providing a total estimate of all results becomes difficult.

Start by reproducing the DOLT_DIFF calls with literal arguments, CONCAT(branch.name, '...branch-x'), and the simplified two-dot form against dolt_branches. Compare these results with the dolt_diff_* tables; done means a supported simple dynamic expression can run the requested three-dot comparison without the reported argument or row errors.