Extract target out of the FileIndexInfo used by UpdateIndexStoreTaskDescription

This way we can guarantee that all files passed to `UpdateIndexStoreTaskDescription` belong to the same target, which will simplify multi-file indexing.

Author: ahoppen

Sources/SemanticIndex/SemanticIndexManager.swift

@@ -91,6 +91,13 @@ private struct InProgressIndexStore {
   var fileModificationDate: Date?
 }
 
+/// The information that's needed to index a file within a given target.
+package struct FileIndexInfo: Sendable, Hashable {
+  package let file: FileToIndex
+  package let target: BuildTargetIdentifier
+  package let outputPath: OutputPath
+}
+
 /// Status of document indexing / target preparation in `inProgressIndexAndPreparationTasks`.
 package enum IndexTaskStatus: Comparable {
   case scheduled
@@ -722,16 +729,18 @@ package final actor SemanticIndexManager {
     }
   }
 
-  /// Update the index store for the given files, assuming that their targets have already been prepared.
+  /// Update the index store for the given files, assuming that their targets has already been prepared.
   private func updateIndexStore(
-    for filesAndTargets: [FileIndexInfo],
+    for fileAndOutputPaths: [FileAndOutputPath],
+    target: BuildTargetIdentifier,
     indexFilesWithUpToDateUnit: Bool,
     preparationTaskID: UUID,
     priority: TaskPriority?
   ) async {
     let taskDescription = AnyIndexTaskDescription(
       UpdateIndexStoreTaskDescription(
-        filesToIndex: filesAndTargets,
+        filesToIndex: fileAndOutputPaths,
+        target: target,
         buildServerManager: self.buildServerManager,
         index: index,
         indexStoreUpToDateTracker: indexStoreUpToDateTracker,
@@ -747,7 +756,12 @@ package final actor SemanticIndexManager {
         self.indexProgressStatusDidChange()
         return
       }
-      for fileAndTarget in filesAndTargets {
+      for fileAndOutputPath in fileAndOutputPaths {
+        let fileAndTarget = FileIndexInfo(
+          file: fileAndOutputPath.file,
+          target: target,
+          outputPath: fileAndOutputPath.outputPath
+        )
         switch self.inProgressIndexTasks[fileAndTarget]?.state {
         case .updatingIndexStore(let registeredTask, _):
           if registeredTask == OpaqueQueuedIndexTask(task) {
@@ -763,7 +777,12 @@ package final actor SemanticIndexManager {
       }
       self.indexProgressStatusDidChange()
     }
-    for fileAndTarget in filesAndTargets {
+    for fileAndOutputPath in fileAndOutputPaths {
+      let fileAndTarget = FileIndexInfo(
+        file: fileAndOutputPath.file,
+        target: target,
+        outputPath: fileAndOutputPath.outputPath
+      )
       switch inProgressIndexTasks[fileAndTarget]?.state {
       case .waitingForPreparation(preparationTaskID, let indexTask), .preparing(preparationTaskID, let indexTask):
         inProgressIndexTasks[fileAndTarget]?.state = .updatingIndexStore(
@@ -938,8 +957,18 @@ package final actor SemanticIndexManager {
             // (https://github.com/swiftlang/sourcekit-lsp/issues/1268)
             for fileBatch in filesByTarget[target]!.partition(intoBatchesOfSize: 1) {
               taskGroup.addTask {
+                let fileAndOutputPaths: [FileAndOutputPath] = fileBatch.compactMap {
+                  guard $0.target == target else {
+                    logger.fault(
+                      "FileIndexInfo refers to different target than should be indexed \($0.target.forLogging) vs \(target.forLogging)"
+                    )
+                    return nil
+                  }
+                  return FileAndOutputPath(file: $0.file, outputPath: $0.outputPath)
+                }
                 await self.updateIndexStore(
-                  for: fileBatch,
+                  for: fileAndOutputPaths,
+                  target: target,
                   indexFilesWithUpToDateUnit: indexFilesWithUpToDateUnit,
                   preparationTaskID: preparationTaskID,
                   priority: priority

Sources/SemanticIndex/UpdateIndexStoreTaskDescription.swift

@@ -79,11 +79,13 @@ package enum FileToIndex: CustomLogStringConvertible, Hashable {
   }
 }
 
-/// The information that's needed to index a file within a given target.
-package struct FileIndexInfo: Sendable, Hashable {
+/// A source file to index and the output path that should be used for indexing.
+package struct FileAndOutputPath: Sendable, Hashable {
   package let file: FileToIndex
-  package let target: BuildTargetIdentifier
   package let outputPath: OutputPath
+
+  fileprivate var mainFile: DocumentURI { file.mainFile }
+  fileprivate var sourceFile: DocumentURI { file.sourceFile }
 }
 
 /// Describes a task to index a set of source files.
@@ -94,7 +96,10 @@ package struct UpdateIndexStoreTaskDescription: IndexTaskDescription {
   package let id = updateIndexStoreIDForLogging.fetchAndIncrement()
 
   /// The files that should be indexed.
-  package let filesToIndex: [FileIndexInfo]
+  package let filesToIndex: [FileAndOutputPath]
+
+  /// The target in whose context the files should be indexed.
+  package let target: BuildTargetIdentifier
 
   /// The build server manager that is used to get the toolchain and build settings for the files to index.
   private let buildServerManager: BuildServerManager
@@ -143,7 +148,8 @@ package struct UpdateIndexStoreTaskDescription: IndexTaskDescription {
   }
 
   init(
-    filesToIndex: [FileIndexInfo],
+    filesToIndex: [FileAndOutputPath],
+    target: BuildTargetIdentifier,
     buildServerManager: BuildServerManager,
     index: UncheckedIndex,
     indexStoreUpToDateTracker: UpToDateTracker<DocumentURI, BuildTargetIdentifier>,
@@ -156,6 +162,7 @@ package struct UpdateIndexStoreTaskDescription: IndexTaskDescription {
     hooks: IndexHooks
   ) {
     self.filesToIndex = filesToIndex
+    self.target = target
     self.buildServerManager = buildServerManager
     self.index = index
     self.indexStoreUpToDateTracker = indexStoreUpToDateTracker
@@ -185,11 +192,7 @@ package struct UpdateIndexStoreTaskDescription: IndexTaskDescription {
       // TODO: Once swiftc supports it, we should group files by target and index files within the same target together
       // in one swiftc invocation. (https://github.com/swiftlang/sourcekit-lsp/issues/1268)
       for fileIndexInfo in filesToIndex {
-        await updateIndexStore(
-          forSingleFile: fileIndexInfo.file,
-          in: fileIndexInfo.target,
-          outputPath: fileIndexInfo.outputPath
-        )
+        await updateIndexStore(forSingleFile: fileIndexInfo.file, outputPath: fileIndexInfo.outputPath)
       }
       // If we know the output paths, make sure that we load their units into indexstore-db. We would eventually also
       // pick the units up through file watching but that would leave a short time period in which we think that
@@ -230,11 +233,7 @@ package struct UpdateIndexStoreTaskDescription: IndexTaskDescription {
     }
   }
 
-  private func updateIndexStore(
-    forSingleFile file: FileToIndex,
-    in target: BuildTargetIdentifier,
-    outputPath: OutputPath
-  ) async {
+  private func updateIndexStore(forSingleFile file: FileToIndex, outputPath: OutputPath) async {
     guard await !indexStoreUpToDateTracker.isUpToDate(file.sourceFile, target) else {
       // If we know that the file is up-to-date without having ot hit the index, do that because it's fastest.
       return

Tests/SourceKitLSPTests/ExpectedIndexTaskTracker.swift

@@ -264,7 +264,7 @@ actor ExpectedIndexTaskTracker {
   }
 }
 
-fileprivate extension FileIndexInfo {
+fileprivate extension FileAndOutputPath {
   var sourceFileName: String? {
     return self.file.sourceFile.fileURL?.lastPathComponent
   }