Bring back links to other symbols in declarations (#277)

* Fix the visibility of operator implementations.

* Only include operators if they have at least one visible implementation.

* Add changelog for #264.

* Bring back links to other symbols in declarations.

* Refactor the search of linked symbols.

* Add changelog entry for #277

Co-authored-by: Mattt <mattt@me.com>

Author: Lukas-Stuehrk

Diff for: Changelog.md

@@ -17,6 +17,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+- Fixed links to type declarations.
+  #277 by @Lukas-Stuehrk.
 - Fixed bug that caused operator implementations to appear in the documentation
   although they should be omitted because of their lower access level.
   #264 by @Lukas-Stuehrk

Diff for: Sources/swift-doc/Subcommands/Generate.swift

@@ -74,7 +74,7 @@ extension SwiftDoc {
           case is Class, is Enumeration, is Structure, is Protocol:
             pages[route(for: symbol)] = TypePage(module: module, symbol: symbol, baseURL: baseURL, includingChildren: symbolFilter)
           case let `typealias` as Typealias:
-            pages[route(for: `typealias`.name)] = TypealiasPage(module: module, symbol: symbol, baseURL: baseURL)
+            pages[route(for: `typealias`.name)] = TypealiasPage(module: module, symbol: symbol, baseURL: baseURL, includingOtherSymbols: symbolFilter)
           case is Operator:
             let operatorPage = OperatorPage(module: module, symbol: symbol, baseURL: baseURL, includingImplementations: symbolFilter)
             if !operatorPage.implementations.isEmpty {
@@ -97,11 +97,11 @@ extension SwiftDoc {
           symbolsByExternalType[extensionDeclaration.extendedType, default: []] += [symbol]
         }
         for (typeName, symbols) in symbolsByExternalType {
-          pages[route(for: typeName)] = ExternalTypePage(module: module, externalType: typeName, symbols: symbols, baseURL: baseURL)
+          pages[route(for: typeName)] = ExternalTypePage(module: module, externalType: typeName, symbols: symbols, baseURL: baseURL, includingOtherSymbols: symbolFilter)
         }
 
         for (name, symbols) in globals {
-            pages[route(for: name)] = GlobalPage(module: module, name: name, symbols: symbols, baseURL: baseURL)
+            pages[route(for: name)] = GlobalPage(module: module, name: name, symbols: symbols, baseURL: baseURL, includingOtherSymbols: symbolFilter)
         }
 
         guard !pages.isEmpty else {

Diff for: Sources/swift-doc/Supporting Types/Components/Declaration.swift

@@ -10,11 +10,13 @@ struct Declaration: Component {
     var symbol: Symbol
     var module: Module
     let baseURL: String
+    let symbolFilter: (Symbol) -> Bool
 
-    init(of symbol: Symbol, in module: Module, baseURL: String) {
+    init(of symbol: Symbol, in module: Module, baseURL: String, includingOtherSymbols symbolFilter: @escaping (Symbol) -> Bool) {
         self.symbol = symbol
         self.module = module
         self.baseURL = baseURL
+        self.symbolFilter = symbolFilter
     }
 
     // MARK: - Component
@@ -30,9 +32,11 @@ struct Declaration: Component {
     var html: HypertextLiteral.HTML {
         let code = symbol.declaration.map { $0.html }.joined()
 
+        let html = linkTypes(of: code, for: symbol, in: module, with: baseURL, includingSymbols: symbolFilter)
+
         return #"""
         <div class="declaration">
-        <pre class="highlight"><code>\#(unsafeUnescaped: code)</code></pre>
+        <pre class="highlight"><code>\#(unsafeUnescaped: html)</code></pre>
         </div>
         """#
     }

Diff for: Sources/swift-doc/Supporting Types/Components/Documentation.swift

@@ -11,11 +11,13 @@ struct Documentation: Component {
     var symbol: Symbol
     var module: Module
     let baseURL: String
+    let symbolFilter: (Symbol) -> Bool
 
-    init(for symbol: Symbol, in module: Module, baseURL: String) {
+    init(for symbol: Symbol, in module: Module, baseURL: String, includingOtherSymbols symbolFilter: @escaping (Symbol) -> Bool) {
         self.symbol = symbol
         self.module = module
         self.baseURL = baseURL
+        self.symbolFilter = symbolFilter
     }
 
     // MARK: - Component
@@ -39,7 +41,7 @@ struct Documentation: Component {
                 Fragment { "\(documentation.summary!.description.escapingEmojiShortcodes)" }
             }
 
-            Declaration(of: symbol, in: module, baseURL: baseURL)
+            Declaration(of: symbol, in: module, baseURL: baseURL, includingOtherSymbols: symbolFilter)
 
             ForEach(in: documentation.discussionParts) { part in
                 DiscussionPart(part, for: symbol, in: module, baseURL: baseURL)
@@ -85,7 +87,7 @@ struct Documentation: Component {
 
         var fragments: [HypertextLiteralConvertible] = []
 
-        fragments.append(Declaration(of: symbol, in: module, baseURL: baseURL))
+        fragments.append(Declaration(of: symbol, in: module, baseURL: baseURL, includingOtherSymbols: symbolFilter))
 
         if let summary = documentation.summary {
             fragments.append(#"""

Diff for: Sources/swift-doc/Supporting Types/Components/Members.swift

@@ -9,6 +9,8 @@ struct Members: Component {
     var module: Module
     let baseURL: String
 
+    let symbolFilter: (Symbol) -> Bool
+
     var members: [Symbol]
 
     var typealiases: [Symbol]
@@ -20,11 +22,13 @@ struct Members: Component {
     var genericallyConstrainedMembers: [[GenericRequirement] : [Symbol]]
     let defaultImplementations: [Symbol]
 
-    init(of symbol: Symbol, in module: Module, baseURL: String, symbolFilter: (Symbol) -> Bool) {
+    init(of symbol: Symbol, in module: Module, baseURL: String, symbolFilter: @escaping (Symbol) -> Bool) {
         self.symbol = symbol
         self.module = module
         self.baseURL = baseURL
 
+        self.symbolFilter = symbolFilter
+
         self.members = module.interface.members(of: symbol)
             .filter { $0.extension?.genericRequirements.isEmpty != false }
             .filter(symbolFilter)
@@ -66,7 +70,7 @@ struct Members: Component {
                             Heading {
                                 Code { member.name }
                             }
-                            Documentation(for: member, in: module, baseURL: baseURL)
+                            Documentation(for: member, in: module, baseURL: baseURL, includingOtherSymbols: symbolFilter)
                         }
                     }
                 }
@@ -83,7 +87,7 @@ struct Members: Component {
                             Section {
                                 ForEach(in: members) { member in
                                     Heading { member.name }
-                                    Documentation(for: member, in: module, baseURL: baseURL)
+                                    Documentation(for: member, in: module, baseURL: baseURL, includingOtherSymbols: symbolFilter)
                                 }
                             }
                         }
@@ -109,7 +113,7 @@ struct Members: Component {
                             <h3>
                                 <code><a href=\#("#\(id)")>\#(softbreak(member.name))</a></code>
                             </h3>
-                            \#(Documentation(for: member, in: module, baseURL: baseURL).html)
+                            \#(Documentation(for: member, in: module, baseURL: baseURL, includingOtherSymbols: symbolFilter).html)
                         </div>
                         """#
                     })
@@ -129,7 +133,7 @@ struct Members: Component {
                         \#(members.map { member -> HypertextLiteral.HTML in
                             #"""
                             <h4>\#(softbreak(member.name))</h4>
-                            \#(Documentation(for: member, in: module, baseURL: baseURL).html)
+                            \#(Documentation(for: member, in: module, baseURL: baseURL, includingOtherSymbols: symbolFilter).html)
                             """#
                         })
                     </section>

Diff for: Sources/swift-doc/Supporting Types/Components/OperatorImplementations.swift

@@ -9,13 +9,16 @@ struct OperatorImplementations: Component {
     var module: Module
     let baseURL: String
 
+    let symbolFilter: (Symbol) -> Bool
+
     var implementations: [Symbol]
 
-    init(of symbol: Symbol, in module: Module, baseURL: String, implementations: [Symbol]) {
+    init(of symbol: Symbol, in module: Module, baseURL: String, implementations: [Symbol], includingOtherSymbols symbolFilter: @escaping (Symbol) -> Bool) {
         self.symbol = symbol
         self.module = module
         self.baseURL = baseURL
         self.implementations = implementations
+        self.symbolFilter = symbolFilter
     }
 
 
@@ -29,7 +32,7 @@ struct OperatorImplementations: Component {
                 Section {
                     Heading { implementation.name }
 
-                    Documentation(for: implementation, in: module, baseURL: baseURL)
+                    Documentation(for: implementation, in: module, baseURL: baseURL, includingOtherSymbols: symbolFilter)
                 }
             }
         }
@@ -77,7 +80,7 @@ struct OperatorImplementations: Component {
                          <a href=\#("#\(id)")>\#(heading)
                          \#(unsafeUnescaped: function.genericWhereClause.map({ #"<small>\#($0.escaped)</small>"# }) ?? "")</a>
                        </h3>
-                       \#(Documentation(for: implementation, in: module, baseURL: baseURL).html)
+                       \#(Documentation(for: implementation, in: module, baseURL: baseURL, includingOtherSymbols: symbolFilter).html)
                    </div>
                    """#
         }

Diff for: Sources/swift-doc/Supporting Types/Components/Requirements.swift

@@ -8,11 +8,13 @@ struct Requirements: Component {
     var symbol: Symbol
     var module: Module
     let baseURL: String
+    let symbolFilter: (Symbol) -> Bool
 
-    init(of symbol: Symbol, in module: Module, baseURL: String) {
+    init(of symbol: Symbol, in module: Module, baseURL: String, includingOtherSymbols symbolFilter: @escaping (Symbol) -> Bool) {
         self.symbol = symbol
         self.module = module
         self.baseURL = baseURL
+        self.symbolFilter = symbolFilter
     }
 
     var sections: [(title: String, requirements: [Symbol])] {
@@ -34,7 +36,7 @@ struct Requirements: Component {
                     Section {
                         ForEach(in: section.requirements) { requirement in
                             Heading { requirement.name.escapingEmojiShortcodes }
-                            Documentation(for: requirement, in: module, baseURL: baseURL)
+                            Documentation(for: requirement, in: module, baseURL: baseURL, includingOtherSymbols: symbolFilter)
                         }
                     }
                 }
@@ -57,7 +59,7 @@ struct Requirements: Component {
                             <h3>
                                 <code>\#(softbreak(member.name))</code>
                             </h3>
-                            \#(Documentation(for: member, in: module, baseURL: baseURL).html)
+                            \#(Documentation(for: member, in: module, baseURL: baseURL, includingOtherSymbols: symbolFilter).html)
                         </div>
                         """#
                     })

Diff for: Sources/swift-doc/Supporting Types/Helpers.swift

@@ -20,6 +20,23 @@ public func linkCodeElements(of html: String, for symbol: Symbol, in module: Mod
     return document.root?.description ?? html
 }
 
+public func linkTypes(of html: String, for symbol: Symbol, in module: Module, with baseURL: String, includingSymbols symbolFilter: (Symbol) -> Bool) -> String {
+    let document = try! Document(string: html.description)!
+    for element in document.search(xpath: "//span[contains(@class,'type')]") {
+        guard let name = element.content else { continue }
+
+        let candidates = module.interface.symbols(named: "\(symbol.name).\(name)", resolvingTypealiases: true).nonEmpty ?? module.interface.symbols(named: name, resolvingTypealiases: true)
+        if let candidate = candidates.filter(symbolFilter).filter({ $0 != symbol }).first
+        {
+            let a = Element(name: "a")
+            a["href"] = path(for: candidate, with: baseURL)
+            element.wrap(inside: a)
+        }
+    }
+
+    return document.root?.description ?? html
+}
+
 public func sidebar(for html: String) -> String {
     let toc = Element(name: "ol")
 
@@ -78,3 +95,9 @@ public func softbreak(_ string: String) -> String {
 
     return regex.stringByReplacingMatches(in: string, options: [], range: NSRange(string.startIndex..<string.endIndex, in: string), withTemplate: "$1\u{200B}$2")
 }
+
+fileprivate extension Collection {
+    var nonEmpty: Self? {
+        return isEmpty ? nil : self
+    }
+}

Diff for: Sources/swift-doc/Supporting Types/Pages/ExternalTypePage.swift

@@ -15,10 +15,13 @@ struct ExternalTypePage: Page {
     let properties: [Symbol]
     let methods: [Symbol]
 
-    init(module: Module, externalType: String, symbols: [Symbol], baseURL: String) {
+    let symbolFilter: (Symbol) -> Bool
+
+    init(module: Module, externalType: String, symbols: [Symbol], baseURL: String, includingOtherSymbols symbolFilter: @escaping (Symbol) -> Bool) {
         self.module = module
         self.externalType = externalType
         self.baseURL = baseURL
+        self.symbolFilter = symbolFilter
 
         self.typealiases = symbols.filter { $0.api is Typealias }
         self.initializers = symbols.filter { $0.api is Initializer }
@@ -49,7 +52,7 @@ struct ExternalTypePage: Page {
                             Heading {
                                 Code { member.name }
                             }
-                            Documentation(for: member, in: module, baseURL: baseURL)
+                            Documentation(for: member, in: module, baseURL: baseURL, includingOtherSymbols: symbolFilter)
                         }
                     }
                 }
@@ -77,7 +80,7 @@ struct ExternalTypePage: Page {
                                <h3>
                                    <code><a href=\#("#\(id)")>\#(softbreak(member.name))</a></code>
                                </h3>
-                               \#(Documentation(for: member, in: module, baseURL: baseURL).html)
+                               \#(Documentation(for: member, in: module, baseURL: baseURL, includingOtherSymbols: symbolFilter).html)
                            </div>
                            """#
                 })

Diff for: Sources/swift-doc/Supporting Types/Pages/GlobalPage.swift

@@ -8,12 +8,14 @@ struct GlobalPage: Page {
     let name: String
     let symbols: [Symbol]
     let baseURL: String
+    let symbolFilter: (Symbol) -> Bool
 
-    init(module: Module, name: String, symbols: [Symbol], baseURL: String) {
+    init(module: Module, name: String, symbols: [Symbol], baseURL: String, includingOtherSymbols symbolFilter: @escaping (Symbol) -> Bool) {
         self.module = module
         self.name = name
         self.symbols = symbols
         self.baseURL = baseURL
+        self.symbolFilter = symbolFilter
     }
 
     // MARK: - Page
@@ -26,7 +28,7 @@ struct GlobalPage: Page {
         return Document {
             ForEach(in: symbols) { symbol in
                 Heading { symbol.id.description }
-                Documentation(for: symbol, in: module, baseURL: baseURL)
+                Documentation(for: symbol, in: module, baseURL: baseURL, includingOtherSymbols: symbolFilter)
             }
         }
     }
@@ -48,7 +50,7 @@ struct GlobalPage: Page {
         </h1>
 
         \#(symbols.map { symbol in
-        Documentation(for: symbol, in: module, baseURL: baseURL).html
+        Documentation(for: symbol, in: module, baseURL: baseURL, includingOtherSymbols: symbolFilter).html
         })
         """#
     }

Diff for: Sources/swift-doc/Supporting Types/Pages/OperatorPage.swift

@@ -8,13 +8,15 @@ struct OperatorPage: Page {
     let symbol: Symbol
     let implementations: [Symbol]
     let baseURL: String
+    let symbolFilter: (Symbol) -> Bool
 
-    init(module: Module, symbol: Symbol, baseURL: String, includingImplementations symbolFilter: (Symbol) -> Bool) {
+    init(module: Module, symbol: Symbol, baseURL: String, includingImplementations symbolFilter: @escaping (Symbol) -> Bool) {
         precondition(symbol.api is Operator)
         self.module = module
         self.symbol = symbol
         self.implementations = module.interface.functionsByOperator[symbol]?.filter(symbolFilter).sorted() ?? []
         self.baseURL = baseURL
+        self.symbolFilter = symbolFilter
     }
 
     // MARK: - Page
@@ -27,7 +29,7 @@ struct OperatorPage: Page {
         return CommonMark.Document {
             Heading { symbol.id.description }
 
-            Documentation(for: symbol, in: module, baseURL: baseURL)
+            Documentation(for: symbol, in: module, baseURL: baseURL, includingOtherSymbols: symbolFilter)
         }
     }
 
@@ -38,8 +40,8 @@ struct OperatorPage: Page {
             <code class="name">\#(softbreak(symbol.id.description))</code>
         </h1>
 
-        \#(Documentation(for: symbol, in: module, baseURL: baseURL).html)
-        \#(OperatorImplementations(of: symbol, in: module, baseURL: baseURL, implementations: implementations).html)
+        \#(Documentation(for: symbol, in: module, baseURL: baseURL, includingOtherSymbols: symbolFilter).html)
+        \#(OperatorImplementations(of: symbol, in: module, baseURL: baseURL, implementations: implementations, includingOtherSymbols: symbolFilter).html)
         """#
     }
 }

Diff for: Sources/swift-doc/Supporting Types/Pages/TypePage.swift

@@ -27,10 +27,10 @@ struct TypePage: Page {
         return CommonMark.Document {
             Heading { symbol.id.description }
 
-            Documentation(for: symbol, in: module, baseURL: baseURL)
+            Documentation(for: symbol, in: module, baseURL: baseURL, includingOtherSymbols: symbolFilter)
             Relationships(of: symbol, in: module, baseURL: baseURL, includingChildren: symbolFilter)
             Members(of: symbol, in: module, baseURL: baseURL, symbolFilter: symbolFilter)
-            Requirements(of: symbol, in: module, baseURL: baseURL)
+            Requirements(of: symbol, in: module, baseURL: baseURL, includingOtherSymbols: symbolFilter)
         }
     }
 
@@ -41,10 +41,10 @@ struct TypePage: Page {
             <code class="name">\#(softbreak(symbol.id.description))</code>
         </h1>
 
-        \#(Documentation(for: symbol, in: module, baseURL: baseURL).html)
+        \#(Documentation(for: symbol, in: module, baseURL: baseURL, includingOtherSymbols: symbolFilter).html)
         \#(Relationships(of: symbol, in: module, baseURL: baseURL, includingChildren: symbolFilter).html)
         \#(Members(of: symbol, in: module, baseURL: baseURL, symbolFilter: symbolFilter).html)
-        \#(Requirements(of: symbol, in: module, baseURL: baseURL).html)
+        \#(Requirements(of: symbol, in: module, baseURL: baseURL, includingOtherSymbols: symbolFilter).html)
         """#
     }
 }