Fix duplicate names in composite components

[gpeairs]

As a consequence of #63, a composite component's subcomponents would not get unique names for their geometry coordinate systems if rendered directly to a Cell (i.e., if render! were called without build!, which replaces comp with geometry(comp) in references). Even prior to that, Path components would get turned into coordinate systems with the path's name, not the unique geometry name, and this would happen whether build! was called first or not.

This fix does a couple things to ensure different components get rendered as coordinate systems with unique names (whether build! is called or not). First, when we encounter a component while rendering to a Cell, we use its coordsys_name (unique by construction, usually name(geometry(comp))) rather than its (non-unique) name(comp) to name the Cell that holds its rendered elements and references.

This doesn't quite solve the Path problem because of the slightly hacky _geometry!(cs, path), which adds the path itself to an intermediate coordinate system path._geometry with a unique name. (We do this for some complicated and subtle reasons where I couldn't find a better solution.) So if we defined coordsys_name(path) = name(geometry(path)), then we'd still end up with a stack of two identically named Cells -- the wrapper from path._geometry, and (in its references) the one containing the path's rendered elements and references. To get around this, coordsys_name(::Path) checks whether path._geometry contains the Path already. If it does, then we use uniquename(name(path)) for the second cell. This is also a little hacky, but as long as we understand that this new function coordsys_name is meant only for this rendering context I don't see it causing any problems.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

📢 Thoughts on this report? Let us know!