fix(client): parse xInfoGroups replies by field

[raashish1601]

Summary

Updates the RESP2 XINFO GROUPS transformer to build each group from the returned field names instead of fixed array positions.

This keeps existing fields working, preserves Redis 7's entries-read and lag fields, and makes the transformer tolerate nullable lag values as documented by Redis. It also corrects the reply type for last-delivered-id to a blob string and allows lag to be null.

Closes #2388.

Redis command reference: https://redis.io/docs/latest/commands/xinfo-groups/

Validation

• direct node -r ts-node/register/transpile-only transformer check for Redis 7 entries-read/lag fields
• npm run lint:changed
• npm run build
• git diff --check

I also attempted npx mocha --require ts-node/register/transpile-only packages/client/lib/commands/XINFO_GROUPS.spec.ts --grep transformReply, but this repo starts its Docker-backed Redis test environment in global hooks before grep-selected tests run. It failed locally at spawn docker ENOENT because Docker is not installed in this environment.

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Note

Medium Risk
Changes the RESP2 reply transformer and types for XINFO GROUPS, which can affect downstream consumers that rely on the previous shape/typing or on positional parsing; behavior should improve but touches command decoding logic.

Overview
Updates XINFO GROUPS RESP2 reply handling to build each group object by field name using transformTuplesReply, instead of reading fixed tuple positions.

Adjusts the reply typing to match Redis behavior (last-delivered-id as a blob string; lag nullable) and adds unit tests covering both pre-Redis-7 and Redis-7+ fields (entries-read, lag) including null values.

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Cursor Bugbot has reviewed your changes and found 1 potential issue.

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Transformer returns null-prototype objects breaking integration test

Medium Severity

transformTuplesReply returns objects created with Object.create(null) (null prototype), but the existing integration test at line 62 expects a regular object literal with Object.prototype. Since the test uses strict assert (i.e., deepStrictEqual), and Node.js 20+ compares [[Prototype]] with ===, the test will fail for all Redis versions. Additionally, for pre-7 Redis, entries-read and lag fields won't exist as properties at all (whereas the old positional code always included them as undefined), causing a further mismatch with the test expectation.

Additional Locations (1)

• packages/client/lib/commands/XINFO_GROUPS.spec.ts#L59-L69

 

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