fix(migrate): guard report timestamp formatting

src/commands/migrate/context.test.ts

@@ -0,0 +1,18 @@
+import path from "node:path";
+import { describe, expect, it } from "vitest";
+import { buildMigrationReportDir } from "./context.js";
+
+describe("migration context helpers", () => {
+  it("builds report directories with filename-safe timestamps", () => {
+    const now = Date.parse("2026-02-23T12:34:56.000Z");
+    expect(buildMigrationReportDir("codex", "/state", now)).toBe(
+      path.join("/state", "migration", "codex", "2026-02-23T12-34-56.000Z"),
+    );
+  });
+
+  it("falls back instead of throwing for out-of-range report timestamps", () => {
+    expect(buildMigrationReportDir("codex", "/state", 9_000_000_000_000_000)).toMatch(
+      /[/\\]migration[/\\]codex[/\\]\d{4}-\d{2}-\d{2}T\d{2}-\d{2}-\d{2}\.\d{3}Z$/,
+    );
+  });
+});

src/commands/migrate/context.ts

@@ -4,6 +4,7 @@ import { resolveStateDir } from "../../config/paths.js";
 import type { OpenClawConfig } from "../../config/types.openclaw.js";
 import type { MigrationProviderContext } from "../../plugins/types.js";
 import type { RuntimeEnv } from "../../runtime.js";
+import { timestampMsToIsoFileStamp } from "../../shared/number-coercion.js";
 
 export function createMigrationLogger(runtime: RuntimeEnv, opts: { json?: boolean } = {}) {
   const info = opts.json ? runtime.error : runtime.log;
@@ -24,7 +25,7 @@ export function buildMigrationReportDir(
   stateDir: string,
   nowMs = Date.now(),
 ): string {
-  const stamp = new Date(nowMs).toISOString().replaceAll(":", "-");
+  const stamp = timestampMsToIsoFileStamp(nowMs);
   return path.join(stateDir, "migration", providerId, stamp);
 }
 

src/config/sessions/artifacts.ts

@@ -1,4 +1,4 @@
-import { timestampMsToIsoString } from "../../shared/number-coercion.js";
+import { timestampMsToIsoFileStamp } from "../../shared/number-coercion.js";
 import { escapeRegExp } from "../../shared/regexp.js";
 
 export type SessionArchiveReason = "bak" | "reset" | "deleted";
@@ -123,11 +123,7 @@ export function parseUsageCountedSessionIdFromFileName(fileName: string): string
 }
 
 export function formatSessionArchiveTimestamp(nowMs = Date.now()): string {
-  const iso =
-    timestampMsToIsoString(nowMs) ??
-    timestampMsToIsoString(Date.now()) ??
-    "1970-01-01T00:00:00.000Z";
-  return iso.replaceAll(":", "-");
+  return timestampMsToIsoFileStamp(nowMs);
 }
 
 function restoreSessionArchiveTimestamp(raw: string): string {

src/shared/number-coercion.test.ts

@@ -25,6 +25,8 @@ import {
   parseStrictNonNegativeInteger,
   parseStrictPositiveInteger,
   resolveTimerTimeoutMs,
+  resolveTimestampMsToIsoString,
+  timestampMsToIsoFileStamp,
   timestampMsToIsoString,
 } from "./number-coercion.js";
 
@@ -132,6 +134,22 @@ describe("number-coercion", () => {
     expect(timestampMsToIsoString("0")).toBeUndefined();
   });
 
+  test("timestamp fallback helpers resolve Date-invalid timestamps", () => {
+    expect(resolveTimestampMsToIsoString(0)).toBe("1970-01-01T00:00:00.000Z");
+    expect(resolveTimestampMsToIsoString(Number.POSITIVE_INFINITY, 1_000)).toBe(
+      "1970-01-01T00:00:01.000Z",
+    );
+    expect(resolveTimestampMsToIsoString(Number.POSITIVE_INFINITY, Number.NaN)).toBe(
+      "1970-01-01T00:00:00.000Z",
+    );
+    expect(timestampMsToIsoFileStamp(Date.parse("2026-02-23T12:34:56.000Z"))).toBe(
+      "2026-02-23T12-34-56.000Z",
+    );
+    expect(timestampMsToIsoFileStamp(9_000_000_000_000_000, 1_000)).toBe(
+      "1970-01-01T00-00-01.000Z",
+    );
+  });
+
   test("expiry helpers resolve safe absolute timestamps", () => {
     expect(
       resolveExpiresAtMsFromDurationSeconds("3600", {

src/shared/number-coercion.ts

@@ -96,6 +96,7 @@ export function asPositiveSafeInteger(value: unknown): number | undefined {
 export const MAX_TIMER_TIMEOUT_MS = 2_147_000_000;
 export const MAX_TIMER_TIMEOUT_SECONDS = Math.floor(MAX_TIMER_TIMEOUT_MS / 1000);
 export const MAX_DATE_TIMESTAMP_MS = 8_640_000_000_000_000;
+export const UNIX_EPOCH_ISO_STRING = "1970-01-01T00:00:00.000Z";
 
 export function asDateTimestampMs(value: unknown): number | undefined {
   return asFiniteNumberInRange(value, {
@@ -109,6 +110,22 @@ export function timestampMsToIsoString(value: unknown): string | undefined {
   return timestampMs === undefined ? undefined : new Date(timestampMs).toISOString();
 }
 
+export function resolveTimestampMsToIsoString(
+  value: unknown,
+  fallbackValue: unknown = Date.now(),
+): string {
+  return (
+    timestampMsToIsoString(value) ?? timestampMsToIsoString(fallbackValue) ?? UNIX_EPOCH_ISO_STRING
+  );
+}
+
+export function timestampMsToIsoFileStamp(
+  value: unknown,
+  fallbackValue: unknown = Date.now(),
+): string {
+  return resolveTimestampMsToIsoString(value, fallbackValue).replaceAll(":", "-");
+}
+
 export function clampTimerTimeoutMs(valueMs: unknown, minMs = 1): number | undefined {
   const value = asFiniteNumber(valueMs);
   if (value === undefined) {