Fix a crash when a topic section contained an unsupported directive (#763)

* Fix a crash when a topic section contained an unsupported directive

rdar://119279890

* Use optional `supportedLanguages` value to require handling  `nil` case

Author: d-ronnqvist

Sources/SwiftDocC/Model/Rendering/RenderNodeTranslator.swift

@@ -1022,12 +1022,12 @@ public struct RenderNodeTranslator: SemanticVisitor {
         contentCompiler: inout RenderContentCompiler
     ) -> [TaskGroupRenderSection] {
         return topics.taskGroups.compactMap { group in
-            let supportedLanguages = Set(group.directives.compactMap {
+            let supportedLanguages = group.directives[SupportedLanguage.directiveName]?.compactMap {
                 SupportedLanguage(from: $0, source: nil, for: bundle, in: context)?.language
-            })
+            }
 
             // If the task group has a set of supported languages, see if it should render for the allowed traits.
-            guard supportedLanguages.isEmpty || supportedLanguages.matchesOneOf(traits: allowedTraits) else {
+            if supportedLanguages?.matchesOneOf(traits: allowedTraits) == false {
                 return nil
             }
 
@@ -1985,7 +1985,7 @@ extension ContentLayout: RenderTree {}
 
 extension ContentRenderSection: RenderTree {}
 
-private extension Set where Element == SourceLanguage {
+private extension Sequence where Element == SourceLanguage {
     func matchesOneOf(traits: Set<DocumentationDataVariantsTrait>) -> Bool {
         traits.contains(where: {
             guard let languageID = $0.interfaceLanguage,

Sources/SwiftDocC/Model/TaskGroup.swift

@@ -223,8 +223,8 @@ public struct TaskGroup {
         self.originalContent = content
     }
 
-    var directives: [BlockDirective] {
-        originalContent.compactMap { $0 as? BlockDirective }
+    var directives: [String: [BlockDirective]] {
+        .init(grouping: originalContent.compactMap { $0 as? BlockDirective }, by: \.name)
     }
 }
 

Tests/SwiftDocCTests/Model/SemaToRenderNodeTests.swift

@@ -12,6 +12,7 @@
 import Markdown
 import XCTest
 import SymbolKit
+import SwiftDocCTestUtilities
 
 class SemaToRenderNodeTests: XCTestCase {
     func testCompileTutorial() throws {
@@ -3345,4 +3346,56 @@ Document
             "doc://org.swift.MixedFramework/documentation/MixedFramework/MyObjectiveCClassSwiftName/myMethod(argument:)"
         ])
     }
+    
+    func testTopicSectionWithUnsupportedDirectives() throws {
+        let exampleDocumentation = Folder(name: "unit-test.docc", content: [
+            TextFile(name: "root.md", utf8Content: """
+                # Main article
+                
+                @Metadata {
+                  @TechnologyRoot
+                }
+                
+                ## Topics
+                
+                ### Something
+                
+                A mix of different directives that aren't supported in task groups.
+                
+                @Comment {
+                  Some commented out markup
+                }
+                
+                @SomeUnknownDirective()
+                
+                - <doc:article>
+                """),
+            
+            TextFile(name: "article.md", utf8Content: """
+                # An article
+                """),
+        ])
+        let tempURL = try createTemporaryDirectory()
+        let bundleURL = try exampleDocumentation.write(inside: tempURL)
+        
+        let (_, bundle, context) = try loadBundle(from: bundleURL) { context in
+            context.diagnosticEngine.consumers.sync({ $0.removeAll() })
+        }
+        
+        let reference = try XCTUnwrap(context.soleRootModuleReference)
+        
+        let documentationNode = try context.entity(with: reference)
+        XCTAssertEqual(documentationNode.availableVariantTraits.count, 1)
+        
+        let converter = DocumentationNodeConverter(bundle: bundle, context: context)
+        let renderNode = try converter.convert(documentationNode, at: nil)
+        
+        let topicSection = renderNode.topicSectionsVariants.defaultValue
+        
+        XCTAssertEqual(topicSection.first?.title, "Something")
+        XCTAssertEqual(topicSection.first?.abstract?.plainText, "A mix of different directives that aren’t supported in task groups.")
+        XCTAssertEqual(topicSection.first?.identifiers, [
+            "doc://unit-test/documentation/unit-test/article"
+        ])
+    }
 }

Tests/SwiftDocCTests/Model/TaskGroupTests.swift

@@ -274,7 +274,8 @@ class TaskGroupTests: XCTestCase {
             XCTAssertEqual(taskGroup.heading?.detachedFromParent.format(), "### Something Swift only")
             XCTAssertEqual(taskGroup.abstract?.paragraph.detachedFromParent.format(), "This link is only for Swift")
             XCTAssertEqual(taskGroup.directives.count, 1)
-            for directive in taskGroup.directives {
+            XCTAssertEqual(taskGroup.directives[SupportedLanguage.directiveName]?.count, 1)
+            for directive in taskGroup.directives[SupportedLanguage.directiveName] ?? [] {
                 XCTAssertEqual(directive.name, "SupportedLanguage")
                 XCTAssertEqual(directive.arguments().count, 1)
             }
@@ -286,7 +287,8 @@ class TaskGroupTests: XCTestCase {
             XCTAssertEqual(taskGroup.heading?.detachedFromParent.format(), "### Something Objective-C only")
             XCTAssertEqual(taskGroup.abstract?.paragraph.detachedFromParent.format(), "This link is only for Objective-C")
             XCTAssertEqual(taskGroup.directives.count, 1)
-            for directive in taskGroup.directives {
+            XCTAssertEqual(taskGroup.directives[SupportedLanguage.directiveName]?.count, 1)
+            for directive in taskGroup.directives[SupportedLanguage.directiveName] ?? [] {
                 XCTAssertEqual(directive.name, "SupportedLanguage")
                 XCTAssertEqual(directive.arguments().count, 1)
             }
@@ -297,8 +299,9 @@ class TaskGroupTests: XCTestCase {
             let taskGroup = try XCTUnwrap(topicSection.taskGroups.dropFirst(2).first)
             XCTAssertEqual(taskGroup.heading?.detachedFromParent.format(), "### Something for both")
             XCTAssertEqual(taskGroup.abstract?.paragraph.detachedFromParent.format(), "This link is for both Swift and Objective-C")
-            XCTAssertEqual(taskGroup.directives.count, 2)
-            for directive in taskGroup.directives {
+            XCTAssertEqual(taskGroup.directives.count, 1)
+            XCTAssertEqual(taskGroup.directives[SupportedLanguage.directiveName]?.count, 2)
+            for directive in taskGroup.directives[SupportedLanguage.directiveName] ?? [] {
                 XCTAssertEqual(directive.name, "SupportedLanguage")
                 XCTAssertEqual(directive.arguments().count, 1)
             }
@@ -314,6 +317,74 @@ class TaskGroupTests: XCTestCase {
         }
     }
 
+    func testOtherDirectivesAreIgnored() throws {
+        let markupSource = """
+            # Title
+            
+            Abstract.
+            
+            ## Topics
+            
+            ### Something
+            
+            A mix of different directives that aren't supported in task groups.
+            
+            @Comment {
+              Some commented out markup
+            }
+            
+            @Metadata {
+            }
+            
+            @SomeUnknownDirective()
+            
+            @SupportedLanguage(swift)
+            
+            - ``SomeLink``
+            
+            """
+        let document = Document(parsing: markupSource, options: [.parseBlockDirectives, .parseSymbolLinks])
+        let markupModel = DocumentationMarkup(markup: document)
+        
+        XCTAssertEqual("Abstract.", Paragraph(markupModel.abstractSection?.content.compactMap { $0 as? InlineMarkup } ?? []).detachedFromParent.format())
+        
+        let topicSection = try XCTUnwrap(markupModel.topicsSection)
+        XCTAssertEqual(topicSection.taskGroups.count, 1)
+        
+        let taskGroup = try XCTUnwrap(topicSection.taskGroups.first)
+        XCTAssertEqual(taskGroup.heading?.detachedFromParent.format(), "### Something")
+        XCTAssertEqual(taskGroup.abstract?.paragraph.detachedFromParent.format(), "A mix of different directives that aren’t supported in task groups.")
+        XCTAssertEqual(taskGroup.directives.count, 4)
+        
+        XCTAssertEqual(taskGroup.directives[Comment.directiveName]?.count, 1)
+        if let comment = taskGroup.directives[Comment.directiveName]?.first {
+            XCTAssertEqual(comment.name, "Comment")
+            XCTAssertEqual(comment.childCount, 1)
+            XCTAssert(comment.arguments().isEmpty)
+        }
+        
+        XCTAssertEqual(taskGroup.directives[Metadata.directiveName]?.count, 1)
+        if let metadata = taskGroup.directives[Metadata.directiveName]?.first {
+            XCTAssertEqual(metadata.name, "Metadata")
+            XCTAssertEqual(metadata.childCount, 0)
+                XCTAssertEqual(metadata.childCount, 0)
+            XCTAssert(metadata.arguments().isEmpty)
+        }
+        
+        if let directive = taskGroup.directives["SomeUnknownDirective"]?.first {
+            XCTAssertEqual(directive.childCount, 0)
+            XCTAssert(directive.arguments().isEmpty)
+        }
+        XCTAssertEqual(taskGroup.directives[SupportedLanguage.directiveName]?.count, 1)
+        if let supportedLanguage = taskGroup.directives[SupportedLanguage.directiveName]?.first {
+            XCTAssertEqual(supportedLanguage.name, "SupportedLanguage")
+            XCTAssertEqual(supportedLanguage.childCount, 0)
+            XCTAssertEqual(supportedLanguage.arguments().count, 1)
+        }
+        
+        XCTAssertEqual(taskGroup.links.count, 1)
+    }
+    
     func testTopicContentOrder() throws {
         func assertExpectedParsedTaskGroupContent(_ content: String, file: StaticString = #file, line: UInt = #line) throws {
             let document = Document(parsing: """
@@ -340,8 +411,9 @@ class TaskGroupTests: XCTestCase {
                 "Discussion paragraph 2",
             ], file: file, line: line)
             XCTAssertEqual(taskGroup.directives.count, 1, file: file, line: line)
-            XCTAssertEqual(taskGroup.directives.first?.name, "SupportedLanguage", file: file, line: line)
-            XCTAssertEqual(taskGroup.directives.first?.arguments().count, 1, file: file, line: line)
+            XCTAssertEqual(taskGroup.directives.keys.first, SupportedLanguage.directiveName, file: file, line: line)
+            XCTAssertEqual(taskGroup.directives[SupportedLanguage.directiveName]?.first?.name, "SupportedLanguage", file: file, line: line)
+            XCTAssertEqual(taskGroup.directives[SupportedLanguage.directiveName]?.first?.arguments().count, 1, file: file, line: line)
             XCTAssertEqual(taskGroup.links.map(\.destination), ["Link1", "Link2"], file: file, line: line)
         }