Add resolution for nested types through typealiases

Author: mattt

Sources/SwiftDoc/Interface.swift

@@ -173,10 +173,19 @@ public final class Interface {
                let `typealias` = symbol.api as? Typealias,
                let initializedType = `typealias`.initializedType
             {
-                pathComponents = (symbol.context.compactMap { ($0 as? Symbol)?.name ?? ($0 as? Extension)?.extendedType }) + [initializedType]
+                let initializedTypePathComponents = initializedType.split(separator: ".")
+                let candidates = symbolsGroupedByIdentifier.keys
+                                    .filter { $0.name == initializedType }
+                                    .filter { $0.pathComponents.count <= initializedTypePathComponents.count }
+                if let id = candidates.max(by: { $0.pathComponents.count > $1.pathComponents.count }) {
+                    pathComponents = id.pathComponents + CollectionOfOne(id.name)
+                } else {
+                    return []
+                }
             }
         }
 
-        return symbolsGroupedByQualifiedName[pathComponents.joined(separator: ".")] ?? []
+        let path = pathComponents.joined(separator: ".")
+        return symbolsGroupedByQualifiedName[path] ?? []
     }
 }

Tests/SwiftDocTests/InterfaceTypeTests.swift

@@ -282,6 +282,10 @@ final class InterfaceTypeTests: XCTestCase {
          }
                       
          public typealias MyClass = SomeClass
+
+         public class AnotherClass {
+             typealias PublicClass = SomeClass
+         }
                      
          public typealias ExternalClass = UIGestureRecognizer
          """#
@@ -306,6 +310,12 @@ final class InterfaceTypeTests: XCTestCase {
         XCTAssertEqual(module.interface.symbols(named: "MyClass.InnerObject", resolvingTypealiases: true).first?.name, "InnerObject")
         XCTAssertNil(module.interface.symbols(named: "MyClass.InnerObject", resolvingTypealiases: false).first)
 
+        XCTAssertEqual(module.interface.symbols(named: "AnotherClass.PublicClass", resolvingTypealiases: true).first?.name, "SomeClass")
+        XCTAssertTrue(module.interface.symbols(named: "AnotherClass.PublicClass", resolvingTypealiases: false).first?.api is Typealias)
+
+        XCTAssertEqual(module.interface.symbols(named: "AnotherClass.PublicClass.ActuallyInternal", resolvingTypealiases: true).first?.name, "InnerStruct")
+        XCTAssertNil(module.interface.symbols(named: "AnotherClass.PublicClass.ActuallyInternal", resolvingTypealiases: false).first)
+
         XCTAssertNil(module.interface.symbols(named: "ExternalClass", resolvingTypealiases: true).first)
         XCTAssertTrue(module.interface.symbols(named: "ExternalClass", resolvingTypealiases: false).first?.api is Typealias)