SPEC-LIBRARY-CURATION.md's first migration, in the order the shepherd approved.
Source only; studio rebuilds (rule 5B — library/ plus eight other owners' plugins).
THE ASYMMETRY, which is why 12 sites each solved it or failed at it separately:
Mapbox getProjection() -> { name } setProjection('mercator')
MapLibre getProjection() -> { type } | undefined setProjection({ type: 'mercator' })
Passing the Mapbox shape to MapLibre THROWS. Measured on regions-dashboard, where
the throw aborted the camera fly so a region dashboard never framed its region.
WHAT THE 12 SITES WERE DOING:
· NINE passed a bare string, so on MapLibre the projection silently never changed.
Eight swallowed the throw in a try/catch; doxa-simple-map.vue:1244 did NOT, so
there it threw uncaught.
· TWO had solved it independently and differently: pplr-data-maps'
setProjectionFor() (instance-tested — the correct one, and the shape adopted)
and regions-dashboard's local pair (config-derived, which is weaker: it trusts
what the page was configured with rather than what the map IS).
· ONE probed by exception, trying the object form and falling back on throw.
The helper reads the engine from the INSTANCE, never from config, because a page can
hold a map built by the other engine. Both functions return something observable —
setProjectionOn returns whether it applied, projectionOf returns null rather than
throwing — on upg100-plugin's argument that a precondition which bails without
recording it is indistinguishable from the request never arriving.
pplrData.setProjectionFor stays as a delegating named export so its three views need
no change.
GATE: _chk-c2-projection-helper-equivalence.mjs, 20 assertions. It runs all THREE old
patterns and the helper against the same stub maps and compares outcomes, rather than
testing the helper alone. Controls prove pattern A really does fail on MapLibre and
leave the projection untouched, and that the bare string really throws — so the
"equivalence" claim has something to be equivalent to. A NEG control catches a helper
that reports success it did not achieve.
★ I DESTROYED 984 LINES OF ANOTHER TEAM'S CODE GETTING HERE, and only the build caught
it. My import-inserting script did `s[:at] + IMPORT` and never appended `s[at:]`, so
every file where the import was ADDED rather than extended was truncated at its last
import line: MapCell.vue -458, FlowerClusters.vue -334, lang-cluster.vue -192.
check:no-free-identifiers PASSED on all three, because a truncated script block is
still valid script. Restored from HEAD and redone with an assertion that a migration
must change the line count by exactly +1 and never remove a line — which is the check
that would have caught it in the first second.
Verified after: all 9 affected bundles build, both gates green, and a per-file line
delta on all 13 changed files with the only negative being the 2 lines I deliberately
deleted from RegionCountryMap when its local pair became an import.
3c69770422