// Test "operation.idhack" when query uses idhack.
db.foo.drop();
db.foo.insert({_id: 0});
oldMetrics = db.serverStatus().metrics;
db.foo.find({_id: 0}).itcount();
newMetrics = db.serverStatus().metrics;
assert.eq(newMetrics.operation.idhack, oldMetrics.operation.idhack + 1);

// Test "queryExecutor.scanned" when query scans index entries.
db.foo.drop();
db.foo.ensureIndex({a: 1});
db.foo.insert({a: 1});
db.foo.insert({a: 2, b: 0});
db.foo.insert({a: 2, b: 1});
db.foo.insert({a: 2, b: 1});
oldMetrics = db.serverStatus().metrics;
db.foo.find({a: 2, b: 1}).hint({a: 1}).itcount();
newMetrics = db.serverStatus().metrics;
assert.eq(newMetrics.queryExecutor.scanned, oldMetrics.queryExecutor.scanned + 3);

// Test "queryExecutor.scannedObjects" when query fetches documents.
db.foo.drop();
db.foo.ensureIndex({a: 1, b: 1});
db.foo.insert({a: 1, b: 1, c: 1});
db.foo.insert({a: 1, b: 1, c: 1});
db.foo.insert({a: 1, b: 2, c: 1});
oldMetrics = db.serverStatus().metrics;
db.foo.find({b: 1, c: 1}).hint({a: 1, b: 1}).itcount();
newMetrics = db.serverStatus().metrics;
assert.eq(newMetrics.queryExecutor.scannedObjects, oldMetrics.queryExecutor.scannedObjects + 3);