const conn = MongoRunner.runMongod(); const db = conn.getDB(jsTestName()); const documentList = [ {_id: 47, "obj" : { "array" : [ "lowercase" ]}}, {_id: 78, "obj" : { "array" : [ "lowercase" ]}}, ]; let coll = db.bf34252; coll.drop(); assert.commandWorked(coll.insert(documentList)); // Create two indexes and run the query twice to create an _active_ plan cache entry. assert.commandWorked(coll.createIndex({ "obj.array" : 1}, { collation: {locale: 'en' }, })); assert.commandWorked(coll.createIndex({ "obj.array" : 1, unused: 1}, { collation: {locale: 'en' }, })); // Sanity check const match2 = { "obj.array" : {$elemMatch: {$gte: "UPPERCASE" }}}; assert.eq(2, coll.find(match2).itcount()); for (let i = 0; i < 2; ++i) { coll.find({ "obj.array" : {$elemMatch: {$gte: NumberLong( "78219" )}}}).itcount(); } assert.eq(2, coll.find(match2).itcount()); // <---- THIS ASSERTION FAILS MongoRunner.stopMongod(conn);