pouchdb-find: error with $elemMatch and array of objects

[plepe]

Issue

I have something like a blog where each doc has comments, which have a user, date, body, ... I'd like to find all docs which have a comment written by a specific user (or at a specific date, does not really matter).

Unfortunately I get an error:

Error: unknown operator "0" - should be one of $eq, $lte, $lt, $gt, $gte, $exists, $ne, $in, $nin, $size, $mod, $regex, $elemMatch, $type or $all
    at match (/path/to/script/node_modules/pouchdb-find/lib/adapters/local/find/in-memory-filter.js:122:11)

Maybe I'm doing something wrong? It's very very similar to nolanlawson/pouchdb-find#118, but it should have been resolved a long time ago. I'm not (yet) using an index, but as I understand the problem it should not matter.

Info

• Environment: Node.js & browser
• Platform: Node.js on Linux, Chrome on Linux (others untested)
• Adapter: LevelDB, IndexedDB
• Server: CouchDB, but also without server DB

I'm using pouchdb-find via npm, version 0.10.5 (current).

Reproduce

I've written a small script which initializes a database with some docs and runs the query:
https://gist.github.com/plepe/44c5f2dfd210c695b4cb4ddb6b254ec8

It fails with the following stack trace:

/path/to/script/testfind.js:47
      if (err) { throw(err) }
                 ^

Error: unknown operator "0" - should be one of $eq, $lte, $lt, $gt, $gte, $exists, $ne, $in, $nin, $size, $mod, $regex, $elemMatch, $type or $all
    at match (/path/to/script/node_modules/pouchdb-find/lib/adapters/local/find/in-memory-filter.js:122:11)
    at /path/to/script/node_modules/pouchdb-find/lib/adapters/local/find/in-memory-filter.js:97:12
    at Array.every (native)
    at matchSelector (/path/to/script/node_modules/pouchdb-find/lib/adapters/local/find/in-memory-filter.js:95:31)
    at /path/to/script/node_modules/pouchdb-find/lib/adapters/local/find/in-memory-filter.js:81:12
    at Array.every (native)
    at rowFilter (/path/to/script/node_modules/pouchdb-find/lib/adapters/local/find/in-memory-filter.js:69:25)
    at /path/to/script/node_modules/pouchdb-find/lib/adapters/local/find/in-memory-filter.js:220:16
    at Array.some (native)
    at Object.$elemMatch (/path/to/script/node_modules/pouchdb-find/lib/adapters/local/find/in-memory-filter.js:219:28)

[nolanlawson]

Have you tested by any chance to see if Cloudant/Couch2 has the same issue? We try to match their behavior exactly.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[zhaochy1990]

@nolanlawson I meet the same issue as @plepe said. I tried my code by Couchdb2 and it works, however the same query by pouchdb throws error.