Merge pull request #28 from tayloraswift/fix-slow-package-correlation-lookup

fix #27

Author: tayloraswift

Sources/UnidocPages/RenderablePage.swift

@@ -58,7 +58,7 @@ extension RenderablePage
                     $0.href = "\(Site.Asset[.main_css])"
                     $0.rel = .stylesheet
                 }
-                if  let canonical:String
+                if  let canonical:String = canonical ?? location
                 {
                     $0[.link]
                     {

Sources/UnidocQueries/Queries/WideQuery.swift

@@ -102,6 +102,8 @@ extension WideQuery:VolumeLookupQuery
                     $0[let: symbol] = Output.Principal[.master] / Volume.Vertex[.symbol]
                     $0[let: hash] = Output.Principal[.master] / Volume.Vertex[.hash]
 
+                    //  ``namesOfLatest`` is always non-nil, so we don’t need to worry about
+                    //  degenerate index behavior.
                     $0[let: min] = Output.Principal[.namesOfLatest] / Volume.Names[.planes_min]
                     $0[let: max] = Output.Principal[.namesOfLatest] / Volume.Names[.planes_max]
                 }

Sources/UnidocQueries/Volumes/VolumeLookupQuery.swift

@@ -94,6 +94,13 @@ extension VolumeLookupQuery
                 $0[.replaceWith] = .init
                 {
                     $0[Self.names] = Mongo.Pipeline.ROOT
+
+                    //  ``Volume.Names`` is complex but not that large, and duplicating this
+                    //  makes the rest of the query a lot simpler.
+                    if  let names:Mongo.KeyPath = Self.namesOfLatest
+                    {
+                        $0[names] = Mongo.Pipeline.ROOT
+                    }
                 }
             }
 

Sources/UnidocRecords/Vertices/Volume.Vertex.swift

@@ -327,6 +327,10 @@ extension Volume.Vertex:BSONDocumentEncodable
             bson[.symbol] = self.symbol
 
         case .meta(let self):
+            //  This must have a value, otherwise it would get lost among all the file
+            //  vertices, and queries for it would be very slow.
+            bson[.hash] = 0
+
             bson[.stem] = ""
             bson[.abi] = self.abi
             bson[.dependencies] = self.dependencies.isEmpty ? nil : self.dependencies