Lookup via ID was quadratic in mdn's panelsFromData. Precompute the m…

…ap instead, function disappears in the noise.

bikeshed/h/__init__.py

@@ -13,6 +13,7 @@
     clearContents,
     closestAncestor,
     closestAttr,
+    collectIds,
     createElement,
     dedupIDs,
     emptyText,

bikeshed/h/dom.py

@@ -1007,6 +1007,17 @@ def circledDigits(num: int) -> str:
     return result
 
 
+def collectIds(el: t.ElementT, ids: dict[str, t.ElementT]|None = None) -> dict[str, t.ElementT]:
+    if ids is None:
+        ids: dict[str, t.ElementT] = {}
+    id = el.get("id", "")
+    if id and id not in ids:
+        ids[id] = el
+    for child in childElements(el):
+        collectIds(child, ids)
+    return ids
+
+
 def createElement(tag: str, attrs: t.Mapping[str, str | None] | None = None, *children: t.NodesT | None) -> t.ElementT:
     if attrs is None:
         attrs = {}

bikeshed/mdn/mdnspeclinks.py

@@ -92,12 +92,13 @@ def panelsFromData(doc: t.SpecT, data: MdnDataT) -> list[t.ElementT]:
 
     panels = []
     missingIds = []
+    docIds = h.collectIds(doc.body)
     for elementId, features in data.items():
         lessThanTwoEngines = 0
         onlyTwoEngines = 0
         allEngines = 0
         featureDivs = []
-        targetElement = h.find(f"[id='{elementId}']", doc)
+        targetElement = docIds.get(elementId)
         if targetElement is None and elementId not in doc.md.ignoreMDNFailure:
             missingIds.append(elementId)
             continue