sr caught a layout change hiding inside a styling one. dx-life's root treatment
carries min-height:400px, and shipping that as part of backdrop:'root' was
tempting because it came with it — but in a scroll stack a min-height is a FLOOR
on the grid band, not a backdrop rule. An empty or heavily-filtered grid that
collapses to a short band today would have become 400px tall with a world map
behind it. That is the shape of thing a reader finds before we do. The floor is
now its own opt-in prop, named for what it does.
And the gate sr asked for. "Every default reproduces today's grid exactly" is
the entire safety argument for putting three consumers on one component, and it
is exactly the kind of claim that is true when written and false three props
later — the grid ships in Big Picture, Simple Research and the studio preview,
so a drifted default moves all three at once, silently, because none of them
passes the prop that changed.
It reads the defaults through the SFC and JS parsers rather than by grep, since
a default is an AST node and a regex cannot tokenise JavaScript. It also asserts
the 400px is not hardcoded anywhere in the backdrop, which is the specific
defect above rather than a general rule. Falsified: flipping the backdrop
default to 'root' turns it red. A negative control pins that the reader really
sees defaults, so the arms are not vacuous.
Simple Research's own answer is recorded in the shape of the code: their filters
stay non-collapsible by default, because a collapsed panel on a map-plus-grid
hides the control a reader came to use.
