Greptile Summary

This PR fixes a dual-instance 503 regression in the Mattermost slash command flow by anchoring the shared accountStates Map to globalThis via Symbol.for(). The root cause — two distinct module loader instances (jiti and native ESM) each holding their own copy of the module-level Map — is correctly diagnosed, and the fix follows the established Node.js pattern for sharing singleton state across module loader boundaries.

Confidence Score: 5/5

Safe to merge — minimal, well-scoped change with a clear rationale and a passing test suite.

The fix is technically correct: Symbol.for() guarantees the same Symbol across module instances, and the ??= initializer ensures only one Map is ever created on globalThis. No logic changes elsewhere, no new surface area introduced, and all 319 extension tests pass.

No files require special attention.

_{Reviews (1): Last reviewed commit: "fix(mattermost): anchor slash command ac..." | Re-trigger Greptile}

Please merge

Please please merge

Any updates on this?

Thanks for the context here. I swept through the related work, and this is now duplicate or superseded.

This PR is a duplicate implementation candidate for the Mattermost native slash-command 503 regression already tracked by open PR #68089 and bug #68113. Current main still has the old dynamic loader plus module-local state, so the bug is not implemented-on-main; cleanup should consolidate review on the earlier, root-cause PR or an equivalent maintainer-owned fix.

Best possible solution:

Close this duplicate PR and consolidate maintainer review on #68089, or land an equivalent root-cause fix that makes route registration and monitor activation share one Mattermost slash-state module instance. Keep #68113 open until the selected fix merges and ships.

What I checked:

• Current main still uses the dynamic bundled-entry loader for the Mattermost slash route: registerSlashCommandRoute loads ./slash-route-api.js through loadBundledEntryExportSync, which is the loader boundary implicated by both PRs. (extensions/mattermost/index.ts:7, 7a23b2d945cc)
• Current main still keeps Mattermost slash state in a module-local Map: accountStates is still a plain module-level new Map, so this PR's globalThis change is not present on main. (extensions/mattermost/src/mattermost/slash-state.ts:35, 7a23b2d945cc)
• The monitor activation path imports the same state module through normal ESM: monitor-slash.ts imports activateSlashCommands from ./slash-state.js, matching the reported dual-loader split between route registration and monitor activation. (extensions/mattermost/src/mattermost/monitor-slash.ts:23, 7a23b2d945cc)
• The loader can evaluate source-side bundled entry modules through jiti: For non-built source modules, loadBundledEntryModuleSync uses getJiti(modulePath) and calls the jiti loader, which supports the duplicate module-instance root cause described in mattermost: fix /oc_* slash command 503 from duplicate slash-state instance #68089 and this PR. (src/plugin-sdk/channel-entry-contract.ts:344, 7a23b2d945cc)
• Earlier canonical implementation candidate already covers the same regression: Provided GitHub context shows mattermost: fix /oc_* slash command 503 from duplicate slash-state instance #68089 is open, predates this PR, targets the same /oc_* Mattermost 503 failure, and proposes the root-cause import-topology fix in extensions/mattermost/index.ts. [Bug]: Mattermost slash commands return 503 "not yet initialized" in v2026.4.15 #68113 remains the linked user bug.

So I’m closing this here and keeping the remaining discussion on the canonical linked item.

Codex review notes: model gpt-5.5, reasoning high; reviewed against 7a23b2d945cc.