fix(codex): improve reused session adoption (#305)

2026-08-08 07:17:39 +00:00 · 2026-03-18 07:26:58 +08:00
parent 9c043b42da
commit f24ea4fea8
2 changed files with 198 additions and 8 deletions
@@ -79,6 +79,10 @@ class CodexSessionScannerImpl extends BaseSessionScanner<CodexSessionEvent> {
    private reportedSessionId: string | null;
    private matchFailed = false;
    private bestWithinWindow: Candidate | null = null;
+    private readonly recentActivitySessionIds = new Set<string>();
+    private firstRecentActivityCandidateResolved = false;
+    private readonly firstRecentActivitySessionIds = new Set<string>();
+    private loggedAmbiguousRecentActivity = false;

    constructor(opts: CodexSessionScannerOptions, targetCwd: string | null) {
        super({ intervalMs: 2000 });
@@ -140,6 +144,7 @@ class CodexSessionScannerImpl extends BaseSessionScanner<CodexSessionEvent> {

    protected async beforeScan(): Promise<void> {
        this.bestWithinWindow = null;
+        this.recentActivitySessionIds.clear();
    }

    protected async findSessionFiles(): Promise<string[]> {
@@ -172,6 +177,10 @@ class CodexSessionScannerImpl extends BaseSessionScanner<CodexSessionEvent> {
                    this.bestWithinWindow = candidate;
                }
            }
+            const recentActivityCandidate = this.getRecentActivityCandidateForFile(filePath, stats.newCount);
+            if (recentActivityCandidate) {
+                this.recentActivitySessionIds.add(recentActivityCandidate.sessionId);
+            }
            if (stats.newCount > 0) {
                logger.debug(`[CODEX_SESSION_SCANNER] Buffered ${stats.newCount} pending events from ${filePath}`);
            }
@@ -189,18 +198,50 @@ class CodexSessionScannerImpl extends BaseSessionScanner<CodexSessionEvent> {
            if (this.bestWithinWindow) {
                logger.debug(`[CODEX_SESSION_SCANNER] Selected session ${this.bestWithinWindow.sessionId} within start window`);
                this.setActiveSessionId(this.bestWithinWindow.sessionId);
-            } else if (Date.now() > this.matchDeadlineMs) {
-                this.matchFailed = true;
-                this.pendingEventsByFile.clear();
-                const message = `No Codex session found within ${this.sessionStartWindowMs}ms for cwd ${this.targetCwd}; refusing fallback.`;
-                logger.warn(`[CODEX_SESSION_SCANNER] ${message}`);
-                this.onSessionMatchFailed?.(message);
-            } else if (this.pendingEventsByFile.size > 0) {
-                logger.debug('[CODEX_SESSION_SCANNER] No session candidate matched yet; pending events buffered');
+            } else {
+                this.captureFirstRecentActivityCandidate();
+
+                if (this.firstRecentActivitySessionIds.size === 1) {
+                    const [sessionId] = this.firstRecentActivitySessionIds;
+                    if (sessionId) {
+                        logger.debug(`[CODEX_SESSION_SCANNER] Selected session ${sessionId} from first unique matching activity after startup`);
+                        this.setActiveSessionId(sessionId);
+                    }
+                } else if (
+                    !this.loggedAmbiguousRecentActivity
+                    && this.firstRecentActivityCandidateResolved
+                    && this.firstRecentActivitySessionIds.size > 1
+                ) {
+                    this.loggedAmbiguousRecentActivity = true;
+                    logger.debug('[CODEX_SESSION_SCANNER] First matching activity after startup was ambiguous; refusing reused-session adoption');
+                }
+
+                if (!this.activeSessionId) {
+                    if (Date.now() > this.matchDeadlineMs) {
+                        this.matchFailed = true;
+                        this.pendingEventsByFile.clear();
+                        const message = `No Codex session found within ${this.sessionStartWindowMs}ms for cwd ${this.targetCwd}; refusing fallback.`;
+                        logger.warn(`[CODEX_SESSION_SCANNER] ${message}`);
+                        this.onSessionMatchFailed?.(message);
+                    } else if (this.pendingEventsByFile.size > 0) {
+                        logger.debug('[CODEX_SESSION_SCANNER] No session candidate matched yet; pending events buffered');
+                    }
+                }
            }
        }
    }

+    private captureFirstRecentActivityCandidate(): void {
+        if (this.firstRecentActivityCandidateResolved || this.recentActivitySessionIds.size === 0) {
+            return;
+        }
+
+        this.firstRecentActivityCandidateResolved = true;
+        for (const sessionId of this.recentActivitySessionIds) {
+            this.firstRecentActivitySessionIds.add(sessionId);
+        }
+    }
+
    private shouldSkipFile(filePath: string): boolean {
        if (!this.activeSessionId) {
            return false;
@@ -351,6 +392,27 @@ class CodexSessionScannerImpl extends BaseSessionScanner<CodexSessionEvent> {
        };
    }

+    private getRecentActivityCandidateForFile(filePath: string, newCount: number): Candidate | null {
+        if (newCount <= 0) {
+            return null;
+        }
+
+        const sessionId = this.sessionIdByFile.get(filePath);
+        if (!sessionId) {
+            return null;
+        }
+
+        const fileCwd = this.sessionCwdByFile.get(filePath);
+        if (this.targetCwd && fileCwd !== this.targetCwd) {
+            return null;
+        }
+
+        return {
+            sessionId,
+            score: 0
+        };
+    }
+
    private getFilesForSession(sessionId: string): string[] {
        const matches: string[] = [];
        for (const [filePath, storedSessionId] of this.sessionIdByFile.entries()) {