mongo/jstests/core/query/array/arrayfind4.js

// @tags: [
//   requires_non_retryable_writes,
//   requires_getmore,
//   # Time series collections do not support indexing array values in measurement fields.
//   exclude_from_timeseries_crud_passthrough,
// ]

// Test query empty array SERVER-2258

let t = db.jstests_arrayfind4;
t.drop();

t.save({a: []});
t.createIndex({a: 1});

assert.eq(1, t.find({a: []}).hint({$natural: 1}).itcount());
assert.eq(1, t.find({a: []}).hint({a: 1}).itcount());

assert.eq(
    1,
    t
        .find({a: {$in: [[]]}})
        .hint({$natural: 1})
        .itcount(),
);
assert.eq(
    1,
    t
        .find({a: {$in: [[]]}})
        .hint({a: 1})
        .itcount(),
);

t.remove({});
t.save({a: [[]]});

assert.eq(1, t.find({a: []}).hint({$natural: 1}).itcount());
assert.eq(1, t.find({a: []}).hint({a: 1}).itcount());

assert.eq(
    1,
    t
        .find({a: {$in: [[]]}})
        .hint({$natural: 1})
        .itcount(),
);
assert.eq(
    1,
    t
        .find({a: {$in: [[]]}})
        .hint({a: 1})
        .itcount(),
);