Store only the resolved reference in DocumentationContext.symbolIndex (…

…#543) (#545)

* Store only the resolved reference in DocumentationContext.symbolIndex

rdar://106654403

* Add test that references in symbol index have nodes in doc cache

Sources/SwiftDocC/Infrastructure/CoverageDataEntry.swift

@@ -1,7 +1,7 @@
 /*
  This source file is part of the Swift.org open source project
 
- Copyright (c) 2021 Apple Inc. and the Swift project authors
+ Copyright (c) 2021-2023 Apple Inc. and the Swift project authors
  Licensed under Apache License v2.0 with Runtime Library Exception
 
  See https://swift.org/LICENSE.txt for license information
@@ -371,9 +371,7 @@ extension CoverageDataEntry {
                 )
                 let total = children.count
                 let documented = children.filter {
-                    (context.symbolIndex[$0.reference.description]?.semantic as? Symbol)?
-                        .abstractSection
-                        != nil
+                    (context.nodeWithSymbolIdentifier($0.reference.description)?.semantic as? Symbol)?.abstractSection != nil
                 }.count
 
                 if total == 0 {

Sources/SwiftDocC/Infrastructure/Link Resolution/DocumentationCacheBasedLinkResolver.swift

@@ -511,7 +511,7 @@ final class DocumentationCacheBasedLinkResolver {
     /// Method called when walking the symbol url tree that checks if a parent of a symbol has had its
     /// path modified during loading the symbol graph. If that's the case the method replaces
     /// `reference` with an updated reference with a correct reference path.
-    func updateNodeWithReferenceIfCollisionChild(_ reference: ResolvedTopicReference, symbolsURLHierarchy: inout BidirectionalTree<ResolvedTopicReference>, symbolIndex: inout [String: DocumentationNode], context: DocumentationContext) throws {
+    func updateNodeWithReferenceIfCollisionChild(_ reference: ResolvedTopicReference, symbolsURLHierarchy: inout BidirectionalTree<ResolvedTopicReference>, symbolIndex: inout [String: ResolvedTopicReference], context: DocumentationContext) throws {
         let newReference = try currentReferenceFor(reference: reference, symbolsURLHierarchy: &symbolsURLHierarchy)
         guard newReference != reference else { return }
 
@@ -523,7 +523,7 @@ final class DocumentationCacheBasedLinkResolver {
         // Rewrite the symbol index
         if let symbolIdentifier = documentationNode?.symbol?.identifier {
             symbolIndex.removeValue(forKey: symbolIdentifier.precise)
-            symbolIndex[symbolIdentifier.precise] = documentationNode
+            symbolIndex[symbolIdentifier.precise] = newReference
         }
 
         // Replace the topic graph node

Sources/SwiftDocC/Infrastructure/Link Resolution/PathHierarchy.swift

@@ -1113,7 +1113,7 @@ private extension PathHierarchy.Node {
             if let fragments = symbol[mixin: SymbolGraph.Symbol.DeclarationFragments.self]?.declarationFragments {
                 return fragments.map(\.spelling).joined().split(whereSeparator: { $0.isWhitespace || $0.isNewline }).joined(separator: " ")
             }
-            return context.symbolIndex[symbol.identifier.precise]!.name.description
+            return context.nodeWithSymbolIdentifier(symbol.identifier.precise)!.name.description
         }
         // This only gets called for PathHierarchy error messages, so hierarchyBasedLinkResolver is never nil.
         let reference = context.hierarchyBasedLinkResolver!.resolvedReferenceMap[identifier]!

Sources/SwiftDocC/Infrastructure/Link Resolution/PathHierarchyBasedLinkResolver.swift

@@ -73,12 +73,12 @@ final class PathHierarchyBasedLinkResolver {
     }
 
     /// Map the resolved identifiers to resolved topic references for all symbols in the given symbol index.
-    func addMappingForSymbols(symbolIndex: [String: DocumentationNode]) {
+    func addMappingForSymbols(symbolIndex: [String: ResolvedTopicReference]) {
         for (id, node) in pathHierarchy.lookup {
-            guard let symbol = node.symbol, let node = symbolIndex[symbol.identifier.precise] else {
+            guard let symbol = node.symbol, let reference = symbolIndex[symbol.identifier.precise] else {
                 continue
             }
-            resolvedReferenceMap[id] = node.reference
+            resolvedReferenceMap[id] = reference
         }
     }
 
@@ -164,9 +164,9 @@ final class PathHierarchyBasedLinkResolver {
     }
 
     /// Adds the headings for all symbols in the symbol index to the path hierarchy.
-    func addAnchorForSymbols(symbolIndex: [String: DocumentationNode]) {
+    func addAnchorForSymbols(symbolIndex: [String: ResolvedTopicReference], documentationCache: [ResolvedTopicReference: DocumentationNode]) {
         for (id, node) in pathHierarchy.lookup {
-            guard let symbol = node.symbol, let node = symbolIndex[symbol.identifier.precise] else { continue }
+            guard let symbol = node.symbol, let reference = symbolIndex[symbol.identifier.precise], let node = documentationCache[reference] else { continue }
             addAnchors(node.anchorSections, to: id)
         }
     }

Sources/SwiftDocC/Infrastructure/Symbol Graph/GeneratedDocumentationTopics.swift

@@ -1,7 +1,7 @@
 /*
  This source file is part of the Swift.org open source project
 
- Copyright (c) 2021-2022 Apple Inc. and the Swift project authors
+ Copyright (c) 2021-2023 Apple Inc. and the Swift project authors
  Licensed under Apache License v2.0 with Runtime Library Exception
 
  See https://swift.org/LICENSE.txt for license information
@@ -255,14 +255,15 @@ enum GeneratedDocumentationTopics {
                // Check that there is origin information (i.e. the symbol is inherited)
                let origin = relationship.mixins[SymbolGraph.Relationship.SourceOrigin.mixinKey] as? SymbolGraph.Relationship.SourceOrigin,
                // Resolve the containing type
-               let parent = context.symbolIndex[relationship.target],
+               let parent = context.nodeWithSymbolIdentifier(relationship.target),
                // Resolve the child
-               let child = context.symbolIndex[relationship.source],
+               let child = context.nodeWithSymbolIdentifier(relationship.source),
                // Get the child symbol
                let childSymbol = child.symbol,
                // Get the swift extension data
-               let extends = childSymbol.mixins[SymbolGraph.Symbol.Swift.Extension.mixinKey] as? SymbolGraph.Symbol.Swift.Extension {
-                let originSymbol = context.symbolIndex[origin.identifier]?.symbol
+               let extends = childSymbol.mixins[SymbolGraph.Symbol.Swift.Extension.mixinKey] as? SymbolGraph.Symbol.Swift.Extension
+            {
+                let originSymbol = context.nodeWithSymbolIdentifier(origin.identifier)?.symbol
 
                 // Add the inherited symbol to the index.
                 try inheritanceIndex.add(child.reference, to: parent.reference, childSymbol: childSymbol, originDisplayName: origin.displayName, originSymbol: originSymbol, extendedModuleName: extends.extendedModule)

Sources/SwiftDocC/Infrastructure/Symbol Graph/SymbolGraphRelationshipsBuilder.swift

@@ -1,7 +1,7 @@
 /*
  This source file is part of the Swift.org open source project
 
- Copyright (c) 2021-2022 Apple Inc. and the Swift project authors
+ Copyright (c) 2021-2023 Apple Inc. and the Swift project authors
  Licensed under Apache License v2.0 with Runtime Library Exception
 
  See https://swift.org/LICENSE.txt for license information
@@ -39,27 +39,29 @@ struct SymbolGraphRelationshipsBuilder {
         selector: UnifiedSymbolGraph.Selector,
         in bundle: DocumentationBundle,
         context: DocumentationContext,
-        symbolIndex: inout [String: DocumentationNode],
+        symbolIndex: inout [String: ResolvedTopicReference],
+        documentationCache: [ResolvedTopicReference: DocumentationNode],
         engine: DiagnosticEngine
     ) {
         // Resolve source symbol
-        guard let implementorNode = symbolIndex[edge.source],
-            let implementorSymbol = implementorNode.semantic as? Symbol else {
+        guard let implementorNode = symbolIndex[edge.source].flatMap({ documentationCache[$0] }),
+              let implementorSymbol = implementorNode.semantic as? Symbol
+        else {
             // The source node for implementation relationship not found.
             engine.emit(NodeProblem.notFound(edge.source))
             return
         }
 
         // Resolve target symbol if possible
-        let optionalInterfaceNode = symbolIndex[edge.target]
+        let optionalInterfaceNode = symbolIndex[edge.target].flatMap { documentationCache[$0] }
 
         if optionalInterfaceNode == nil {
             // Take the interface language of the target symbol
             // or if external - default to the language of the current symbol.
-            let language = symbolIndex[edge.target]?.reference.sourceLanguage
+            let language = symbolIndex[edge.target]?.sourceLanguage
                 ?? implementorNode.reference.sourceLanguage
 
-            let symbolReference = SymbolReference(edge.target, interfaceLanguage: language, symbol: symbolIndex[edge.target]?.symbol)
+            let symbolReference = SymbolReference(edge.target, interfaceLanguage: language, symbol: symbolIndex[edge.target].flatMap { documentationCache[$0]?.symbol })
             guard let unresolved = UnresolvedTopicReference(symbolReference: symbolReference, bundle: bundle) else {
                 // The symbol reference format is invalid.
                 engine.emit(NodeProblem.invalidReference(symbolReference.path))
@@ -74,9 +76,10 @@ struct SymbolGraphRelationshipsBuilder {
         // Find out the parent's title
         let parentName: String?
 
-        if let reference = symbolIndex[edge.source]?.reference,
-            let parentNode = try? context.entity(with: reference.removingLastPathComponent()),
-            let title = (parentNode.semantic as? Symbol)?.title {
+        if let reference = symbolIndex[edge.source],
+           let parentNode = try? context.entity(with: reference.removingLastPathComponent()),
+           let title = (parentNode.semantic as? Symbol)?.title
+        {
             parentName = title
         } else {
             parentName = nil
@@ -93,14 +96,14 @@ struct SymbolGraphRelationshipsBuilder {
             )
 
             // Make the implementation a child of the requirement
-            guard let childReference = symbolIndex[edge.source]?.reference else {
+            guard let childReference = symbolIndex[edge.source] else {
                 // The child wasn't found, invalid reference in relationship.
                 engine.emit(SymbolGraphRelationshipsBuilder.NodeProblem.notFound(edge.source))
                 return
             }
 
             if let child = context.topicGraph.nodeWithReference(childReference),
-                let targetReference = symbolIndex[edge.target]?.reference,
+                let targetReference = symbolIndex[edge.target],
                 let parent = context.topicGraph.nodeWithReference(targetReference) {
                 context.topicGraph.addEdge(from: parent, to: child)
             }
@@ -119,30 +122,32 @@ struct SymbolGraphRelationshipsBuilder {
         edge: SymbolGraph.Relationship,
         selector: UnifiedSymbolGraph.Selector,
         in bundle: DocumentationBundle,
-        symbolIndex: inout [String: DocumentationNode],
+        symbolIndex: inout [String: ResolvedTopicReference],
+        documentationCache: [ResolvedTopicReference: DocumentationNode],
         engine: DiagnosticEngine
     ) {
         // Resolve source symbol
-        guard let conformingNode = symbolIndex[edge.source],
-            let conformingSymbol = conformingNode.semantic as? Symbol else {
-            // The source node for coformance relationship not found.
+        guard let conformingNode = symbolIndex[edge.source].flatMap({ documentationCache[$0] }),
+              let conformingSymbol = conformingNode.semantic as? Symbol
+        else {
+            // The source node for conformance relationship not found.
             engine.emit(NodeProblem.notFound(edge.source))
             return
         }
 
         // Resolve target symbol if possible
-        let optionalConformanceNode = symbolIndex[edge.target]
+        let optionalConformanceNode = symbolIndex[edge.target].flatMap { documentationCache[$0] }
         let conformanceNodeReference: TopicReference
 
         if let conformanceNode = optionalConformanceNode {
             conformanceNodeReference = .successfullyResolved(conformanceNode.reference)
         } else {
             // Take the interface language of the target symbol
             // or if external - default to the language of the current symbol.
-            let language = symbolIndex[edge.target]?.reference.sourceLanguage
+            let language = symbolIndex[edge.target]?.sourceLanguage
                 ?? conformingNode.reference.sourceLanguage
 
-            let symbolReference = SymbolReference(edge.target, interfaceLanguage: language, symbol: symbolIndex[edge.target]?.symbol)
+            let symbolReference = SymbolReference(edge.target, interfaceLanguage: language, symbol: symbolIndex[edge.target].flatMap { documentationCache[$0]?.symbol })
             guard let unresolved = UnresolvedTopicReference(symbolReference: symbolReference, bundle: bundle) else {
                 // The symbol reference format is invalid.
                 engine.emit(NodeProblem.invalidReference(symbolReference.path))
@@ -203,29 +208,32 @@ struct SymbolGraphRelationshipsBuilder {
         edge: SymbolGraph.Relationship,
         selector: UnifiedSymbolGraph.Selector,
         in bundle: DocumentationBundle,
-        symbolIndex: inout [String: DocumentationNode],
+        symbolIndex: inout [String: ResolvedTopicReference],
+        documentationCache: [ResolvedTopicReference: DocumentationNode],
         engine: DiagnosticEngine
     ) {
         // Resolve source symbol
-        guard let childNode = symbolIndex[edge.source],
-            let childSymbol = childNode.semantic as? Symbol else {
+        guard let childNode = symbolIndex[edge.source].flatMap({ documentationCache[$0] }),
+              let childSymbol = childNode.semantic as? Symbol
+        else {
             // The source node for inheritance relationship not found.
             engine.emit(NodeProblem.notFound(edge.source))
             return
         }
 
         // Resolve target symbol if possible
-        let optionalParentNode = symbolIndex[edge.target]
+        let optionalParentNode = symbolIndex[edge.target].flatMap { documentationCache[$0] }
         let parentNodeReference: TopicReference
 
         if let parentNode = optionalParentNode {
             parentNodeReference = .successfullyResolved(parentNode.reference)
         } else {
-            // Use the target symbol language, if external - fallback on child symbol's langauge
-            let language = symbolIndex[edge.target]?.symbol.map({ SourceLanguage(id: $0.identifier.interfaceLanguage) })
-                ?? childNode.reference.sourceLanguage
+            // Use the target symbol language, if external - fallback on child symbol's language
+            let language: SourceLanguage = symbolIndex[edge.target].flatMap {
+                documentationCache[$0]?.symbol.map({ SourceLanguage(id: $0.identifier.interfaceLanguage) })
+            } ?? childNode.reference.sourceLanguage
 
-            let symbolReference = SymbolReference(edge.target, interfaceLanguage: language, symbol: symbolIndex[edge.target]?.symbol)
+            let symbolReference = SymbolReference(edge.target, interfaceLanguage: language, symbol: symbolIndex[edge.target].flatMap { documentationCache[$0]?.symbol })
             guard let unresolved = UnresolvedTopicReference(symbolReference: symbolReference, bundle: bundle) else {
                 // The symbol reference format is invalid.
                 engine.emit(NodeProblem.invalidReference(symbolReference.path))
@@ -267,14 +275,16 @@ struct SymbolGraphRelationshipsBuilder {
         edge: SymbolGraph.Relationship,
         selector: UnifiedSymbolGraph.Selector,
         in bundle: DocumentationBundle,
-        symbolIndex: inout [String: DocumentationNode],
+        symbolIndex: inout [String: ResolvedTopicReference],
+        documentationCache: [ResolvedTopicReference: DocumentationNode],
         engine: DiagnosticEngine
     ) {
         addProtocolRelationship(
             edge: edge,
             selector: selector,
             in: bundle,
             symbolIndex: &symbolIndex,
+            documentationCache: documentationCache,
             engine: engine,
             required: true
         )
@@ -291,14 +301,16 @@ struct SymbolGraphRelationshipsBuilder {
         edge: SymbolGraph.Relationship,
         selector: UnifiedSymbolGraph.Selector,
         in bundle: DocumentationBundle,
-        symbolIndex: inout [String: DocumentationNode],
+        symbolIndex: inout [String: ResolvedTopicReference],
+        documentationCache: [ResolvedTopicReference: DocumentationNode],
         engine: DiagnosticEngine
     ) {
         addProtocolRelationship(
             edge: edge,
             selector: selector,
             in: bundle,
             symbolIndex: &symbolIndex,
+            documentationCache: documentationCache,
             engine: engine,
             required: false
         )
@@ -316,12 +328,15 @@ struct SymbolGraphRelationshipsBuilder {
         edge: SymbolGraph.Relationship,
         selector: UnifiedSymbolGraph.Selector,
         in bundle: DocumentationBundle,
-        symbolIndex: inout [String: DocumentationNode],
+        symbolIndex: inout [String: ResolvedTopicReference],
+        documentationCache: [ResolvedTopicReference: DocumentationNode],
         engine: DiagnosticEngine, required: Bool
     ) {
         // Resolve source symbol
-        guard let requiredNode = symbolIndex[edge.source],
-            let requiredSymbol = requiredNode.semantic as? Symbol else {
+        guard let requiredNodeRef = symbolIndex[edge.source],
+              let requiredNode = documentationCache[requiredNodeRef],
+              let requiredSymbol = requiredNode.semantic as? Symbol
+        else {
             // The source node for requirement relationship not found.
             engine.emit(NodeProblem.notFound(edge.source))
             return
@@ -341,8 +356,8 @@ struct SymbolGraphRelationshipsBuilder {
     static func addInheritedDefaultImplementation(
         edge: SymbolGraph.Relationship,
         context: DocumentationContext, 
-        symbolIndex: inout [String: DocumentationNode], 
-        moduleName: String, 
+        symbolIndex: inout [String: ResolvedTopicReference],
+        moduleName: String,
         engine: DiagnosticEngine
     ) {
         func setAsInheritedSymbol(origin: SymbolGraph.Relationship.SourceOrigin, for node: inout DocumentationNode, originNode: DocumentationNode?) {
@@ -374,13 +389,11 @@ struct SymbolGraphRelationshipsBuilder {
         // verify we have the matching data in symbolIndex and documentationCache
         // and add the origin data to the symbol.
         if let origin = edge.mixins[SymbolGraph.Relationship.SourceOrigin.mixinKey] as? SymbolGraph.Relationship.SourceOrigin,
-           let node = symbolIndex[edge.source],
-           node.semantic is Symbol,
-           context.documentationCache.keys.contains(node.reference) {
-
+           let reference = symbolIndex[edge.source],
+           context.documentationCache[reference]?.semantic is Symbol
+        {
             // OK to unwrap - we've verified the existence of the key above.
-            setAsInheritedSymbol(origin: origin, for: &symbolIndex[edge.source]!, originNode: symbolIndex[origin.identifier])
-            setAsInheritedSymbol(origin: origin, for: &context.documentationCache[node.reference]!, originNode: symbolIndex[origin.identifier])
+            setAsInheritedSymbol(origin: origin, for: &context.documentationCache[reference]!, originNode: symbolIndex[origin.identifier].flatMap { context.documentationCache[$0] })
         }
     }
 }