// ensure strings containing null characters dont end at that null c = db.s6556; c.drop(); c.save({foo:"as\0df"}); // compare the whole string, they should match assert.eq(c.aggregate({$project: {_id: 0, matches: {$eq:["as\0df", "$foo"]}}}).toArray(), [{matches:true}]); // compare with the substring containing only the up to the null, they should not match assert.eq(c.aggregate({$project: {_id: 0, matches: {$eq:["as\0df", {$substr:["$foo",0,3]}]}}}).toArray(), [{matches:false}]); // partial the other way shouldnt work either assert.eq(c.aggregate({$project: {_id: 0, matches: {$eq:["as", "$foo"]}}}).toArray(), [{matches:false}]); // neither should one that differs after the null assert.eq(c.aggregate({$project: {_id: 0, matches: {$eq:["as\0de", "$foo"]}}}).toArray(), [{matches:false}]); // should assert on fieldpaths with a null assert.throws( function() { c.aggregate({$project: {_id: 0, matches: {$eq:["as\0df", "$f\0oo"]}}}) });