feat(converter): 複数入力セッションでConverterを共有可能にする

Sources/KanaKanjiConverterModule/ConverterAPI/KanaKanjiConverter.swift

@@ -13,6 +13,15 @@ import SwiftUtils
 
 /// かな漢字変換の管理を受け持つクラス
 public final class KanaKanjiConverter {
+    /// 1つのConverterを複数の入力セッションで共有するための識別子。
+    public struct ConversionSessionID: Hashable, Sendable {
+        fileprivate let rawValue: String
+    }
+
+    public enum ConversionSessionError: Error, Equatable, Sendable {
+        case unknownSession(ConversionSessionID)
+    }
+
     private let converter: Kana2Kanji
     private struct ConversionSessionState {
         var previousInputData: ComposingText?
@@ -23,9 +32,9 @@ public final class KanaKanjiConverter {
         var ngramCache: NGramCache = .init()
         var predictiveInputCache: PredictiveInputCacheEntry?
         var stablePredictionCandidateCache: StablePredictionCandidateCacheEntry?
+        var lastData: DicdataElement?
     }
-    private typealias SessionID = String
-    private static let defaultSessionID: SessionID = "default"
+    private static let defaultSessionID = ConversionSessionID(rawValue: "default")
 
     public init(dicdataStore: DicdataStore) {
         self.converter = .init(dicdataStore: dicdataStore)
@@ -51,9 +60,10 @@ public final class KanaKanjiConverter {
     private var checkerInitialized: [KeyboardLanguage: Bool] = [.none: true, .ja_JP: true]
 
     // 前回の変換や確定の情報を取っておく部分。
-    private var sessions: [SessionID: ConversionSessionState] = ["default": .init()]
-    private var activeSessionID: SessionID = "default"
-    private var lastData: DicdataElement?
+    private var sessions: [ConversionSessionID: ConversionSessionState] = [
+        KanaKanjiConverter.defaultSessionID: .init()
+    ]
+    private var activeSessionID = KanaKanjiConverter.defaultSessionID
     /// Zenzaiのためのzenzモデル
     private var zenz: Zenz?
     /// 完全な入力・文脈・制約をキーにする純粋なメモ化結果。
@@ -73,8 +83,50 @@ public final class KanaKanjiConverter {
         self.sessions[self.activeSessionID] = state
     }
 
+    /// 独立した変換状態を持つセッションを作成します。
+    ///
+    /// 辞書、モデル、学習データ、Converter単位のメモ化キャッシュは同じ
+    /// `KanaKanjiConverter`インスタンス内で共有されます。
+    public func createSession() -> ConversionSessionID {
+        let sessionID = ConversionSessionID(rawValue: UUID().uuidString)
+        self.sessions[sessionID] = .init()
+        return sessionID
+    }
+
+    /// 作成済みの変換セッションを破棄します。
+    public func removeSession(_ sessionID: ConversionSessionID) {
+        guard sessionID != Self.defaultSessionID else {
+            self.sessions[sessionID] = .init()
+            return
+        }
+        self.sessions[sessionID] = nil
+        if self.activeSessionID == sessionID {
+            self.activeSessionID = Self.defaultSessionID
+        }
+    }
+
+    /// 指定したセッションを有効にして同期処理を実行します。
+    ///
+    /// `KanaKanjiConverter`はスレッドセーフではありません。複数の実行コンテキストから
+    /// 利用する場合、呼び出し側でこのメソッドを含むConverterアクセスを直列化してください。
+    /// `operation`終了時には、ネストした呼び出しを含めて元のセッションへ戻ります。
+    public func withSession<Result>(
+        _ sessionID: ConversionSessionID,
+        operation: () throws -> Result
+    ) throws -> Result {
+        guard self.sessions[sessionID] != nil else {
+            throw ConversionSessionError.unknownSession(sessionID)
+        }
+        let previousSessionID = self.activeSessionID
+        self.activeSessionID = sessionID
+        defer {
+            self.activeSessionID = previousSessionID
+        }
+        return try operation()
+    }
+
     private func withScratchSession<T>(_ body: () -> T) -> T {
-        let scratchID: SessionID = "scratch-\(UUID().uuidString)"
+        let scratchID = ConversionSessionID(rawValue: "scratch-\(UUID().uuidString)")
         self.sessions[scratchID] = self.currentSessionState
         let previousSessionID = self.activeSessionID
         let savedPersonalization = self.zenzaiPersonalization
@@ -91,9 +143,7 @@ public final class KanaKanjiConverter {
     public func stopComposition() {
         self.zenz?.endSession()
         self.zenzaiPersonalization = nil
-        self.sessions = [Self.defaultSessionID: .init()]
-        self.activeSessionID = Self.defaultSessionID
-        self.lastData = nil
+        self.sessions[self.activeSessionID] = .init()
     }
 
     /// Zenzaiの純粋なメモ化結果を明示的に破棄します。
@@ -394,8 +444,10 @@ public final class KanaKanjiConverter {
     /// - Warning:
     ///   `commitUpdateLearningData`を呼び出すまで永続化されません。
     public func updateLearningData(_ candidate: Candidate) {
-        self.dicdataStoreState.updateLearningData(candidate, with: self.lastData)
-        self.lastData = candidate.data.last
+        self.dicdataStoreState.updateLearningData(candidate, with: self.currentSessionState.lastData)
+        self.updateCurrentSessionState {
+            $0.lastData = candidate.data.last
+        }
     }
 
     /// 確定操作後、学習メモリをアップデートする関数。
@@ -405,7 +457,9 @@ public final class KanaKanjiConverter {
     ///   `commitUpdateLearningData`を呼び出すまで永続化されません。
     public func updateLearningData(_ candidate: Candidate, with predictionCandidate: PostCompositionPredictionCandidate) {
         self.dicdataStoreState.updateLearningData(candidate, with: predictionCandidate)
-        self.lastData = predictionCandidate.lastData
+        self.updateCurrentSessionState {
+            $0.lastData = predictionCandidate.lastData
+        }
     }
 
     /// 確定操作後の学習メモリの更新を確定させます。

Sources/KanaKanjiConverterModule/DictionaryManagement/DicdataStoreState.swift

@@ -128,8 +128,9 @@ package final class DicdataStoreState {
     }
 
     func saveMemory() {
-        self.learningMemoryManager.save()
-        self.resetMemoryLOUDSCache()
+        if self.learningMemoryManager.save() {
+            self.resetMemoryLOUDSCache()
+        }
     }
 
     func resetMemory() {

Sources/KanaKanjiConverterModule/DictionaryManagement/LearningMemory.swift

@@ -449,6 +449,10 @@ struct TemporalLearningMemoryTrie {
     fileprivate var dicdata: [DicdataElement] = []
     fileprivate var metadata: [MetadataElement] = []
 
+    var isEmpty: Bool {
+        self.dicdata.isEmpty
+    }
+
     /// 同じノードにあることがわかっているデータを一括で追加する場面で利用する関数
     /// 主にマージ時の利用を想定
     fileprivate mutating func append(dicdata: [DicdataElement], chars: [UInt8], metadata: [MetadataElement]) {
@@ -848,11 +852,16 @@ final class LearningManager {
         self.memoryCollapsed = LongTermLearningMemory.memoryCollapsed(directoryURL: memoryURL)
     }
 
-    func save() {
+    @discardableResult
+    func save() -> Bool {
         guard self.config.learningType.needUpdateMemory,
               let memoryURL = config.memoryURL else {
             debug(#function, "config.learningType=\(self.config.learningType as _?)", "skip memory update")
-            return
+            return false
+        }
+        guard !self.temporaryMemory.isEmpty else {
+            debug(#function, "skip because there is no pending memory")
+            return false
         }
         do {
             try LongTermLearningMemory.merge(tempTrie: self.temporaryMemory, directoryURL: memoryURL, maxMemoryCount: self.config.maxMemoryCount, char2UInt8: char2UInt8)
@@ -864,6 +873,7 @@ final class LearningManager {
         }
         // 状態を更新する
         self.memoryCollapsed = LongTermLearningMemory.memoryCollapsed(directoryURL: memoryURL)
+        return true
     }
 
     func resetMemory() {

Tests/KanaKanjiConverterModuleTests/DictionaryManagement/LearningMemoryTests.swift

@@ -8,6 +8,22 @@ final class LearningMemoryTests: XCTestCase {
         .init(learningType: .inputAndOutput, maxMemoryCount: 32, memoryURL: memoryURL)
     }
 
+    func testSaveSkipsWhenNoPendingMemory() throws {
+        let dir = FileManager.default.temporaryDirectory.appendingPathComponent("LearningMemoryTest-\(UUID().uuidString)", isDirectory: true)
+        try FileManager.default.createDirectory(at: dir, withIntermediateDirectories: true)
+        defer { try? FileManager.default.removeItem(at: dir) }
+
+        let manager = LearningManager(dictionaryURL: Self.resourceURL)
+        _ = manager.updateConfig(self.getConfigForMemoryTest(memoryURL: dir))
+
+        XCTAssertFalse(manager.save())
+
+        let element = DicdataElement(word: "テスト", ruby: "テスト", cid: CIDData.一般名詞.cid, mid: MIDData.一般.mid, value: -10)
+        manager.update(data: [element])
+        XCTAssertTrue(manager.save())
+        XCTAssertFalse(manager.save())
+    }
+
     func testPauseFileIsClearedOnInit() throws {
         let dir = FileManager.default.temporaryDirectory.appendingPathComponent("LearningMemoryTest-\(UUID().uuidString)", isDirectory: true)
         try FileManager.default.createDirectory(at: dir, withIntermediateDirectories: true)

Tests/KanaKanjiConverterModuleWithDefaultDictionaryTests/ConverterTests/ConverterSessionTests.swift

@@ -0,0 +1,76 @@
+import Foundation
+@testable import KanaKanjiConverterModuleWithDefaultDictionary
+import XCTest
+
+final class ConverterSessionTests: XCTestCase {
+    func testStopCompositionOnlyResetsActiveSession() throws {
+        let converter = KanaKanjiConverter.withDefaultDictionary()
+        let firstSession = converter.createSession()
+        let secondSession = converter.createSession()
+
+        try converter.withSession(firstSession) {
+            converter.stopComposition()
+        }
+
+        XCTAssertNoThrow(
+            try converter.withSession(secondSession) {
+                var composingText = ComposingText()
+                composingText.insertAtCursorPosition("あずーきー", inputStyle: .direct)
+                _ = converter.requestCandidates(composingText, options: requestOptions())
+            }
+        )
+    }
+
+    func testRemovedSessionCannotBeSelected() throws {
+        let converter = KanaKanjiConverter.withDefaultDictionary()
+        let removedSession = converter.createSession()
+        let remainingSession = converter.createSession()
+
+        converter.removeSession(removedSession)
+
+        XCTAssertThrowsError(try converter.withSession(removedSession) {}) { error in
+            XCTAssertEqual(
+                error as? KanaKanjiConverter.ConversionSessionError,
+                .unknownSession(removedSession)
+            )
+        }
+        XCTAssertNoThrow(try converter.withSession(remainingSession) {})
+    }
+
+    func testNestedSessionSelectionRestoresOuterSession() throws {
+        let converter = KanaKanjiConverter.withDefaultDictionary()
+        let outerSession = converter.createSession()
+        let innerSession = converter.createSession()
+
+        try converter.withSession(outerSession) {
+            try converter.withSession(innerSession) {
+                converter.stopComposition()
+            }
+            converter.stopComposition()
+        }
+
+        XCTAssertNoThrow(try converter.withSession(outerSession) {})
+        XCTAssertNoThrow(try converter.withSession(innerSession) {})
+    }
+
+    private func requestOptions() -> ConvertRequestOptions {
+        ConvertRequestOptions(
+            N_best: 10,
+            requireJapanesePrediction: .disabled,
+            requireEnglishPrediction: .disabled,
+            keyboardLanguage: .ja_JP,
+            englishCandidateInRoman2KanaInput: true,
+            fullWidthRomanCandidate: false,
+            halfWidthKanaCandidate: false,
+            learningType: .nothing,
+            maxMemoryCount: 0,
+            shouldResetMemory: false,
+            memoryDirectoryURL: URL(fileURLWithPath: ""),
+            sharedContainerURL: URL(fileURLWithPath: ""),
+            textReplacer: .empty,
+            specialCandidateProviders: [],
+            typoCorrectionMode: .disabled,
+            metadata: nil
+        )
+    }
+}