Column cog shows "facet by this" when already default faceted

[simonw]

e.g. on https://covid-19.datasettes.com/covid/economist_excess_deaths

But if you add ?_facet=country to the URL that goes away: https://covid-19.datasettes.com/covid/economist_excess_deaths?_facet_size=5&_facet=country

The logic that decides if the "Facet by this" item is shown does not take default metadata.json facets into account.

[simonw]

Here's the code at fault:

datasette/datasette/static/table.js

Lines 137 to 146 in b28b6cd

	if (
	isFirstColumn ||
	params.getAll("_facet").includes(column) ||
	isSinglePk
	) {
	facetItem.parentNode.style.display = "none";
	} else {
	facetItem.parentNode.style.display = "block";
	facetItem.setAttribute("href", facetUrl(column));
	}

[simonw]

The core problem here is treating the ?_facet= query string parameters as the point of truth for which facets are currently enabled.

Instead, I could use a data- attribute on the displayed facets.