t = db.getCollection("where1");
t.drop();

t.save({a: 1});
t.save({a: 2});
t.save({a: 3});

assert.eq(1,
          t.find(function() {
              return this.a == 2;
          }).length(),
          "A");

assert.eq(1, t.find({$where: "return this.a == 2"}).toArray().length, "B");
assert.eq(1, t.find({$where: "this.a == 2"}).toArray().length, "C");

assert.eq(1, t.find("this.a == 2").toArray().length, "D");

// SERVER-12117
// positional $ projection should fail on a $where query
assert.throws(function() {
    t.find({$where: "return this.a;"}, {'a.$': 1}).itcount();
});

// SERVER-12439: $where must be top-level
assert.throws(function() {
    t.find({a: 1, b: {$where: "this.a;"}}).itcount();
});
assert.throws(function() {
    t.find({a: {$where: "this.a;"}}).itcount();
});
assert.throws(function() {
    t.find({a: {$elemMatch: {$where: "this.a;"}}}).itcount();
});
assert.throws(function() {
    t.find({a: 3, "b.c": {$where: "this.a;"}}).itcount();
});

// SERVER-13503
assert.throws(function() {
    t.find({a: {$elemMatch: {$where: "this.a;", b: 1}}}).itcount();
});
assert.throws(function() {
    t.find({a: {$elemMatch: {b: 1, $where: "this.a;"}}}).itcount();
});
assert.throws(function() {
    t.find({a: {$elemMatch: {$and: [{b: 1}, {$where: "this.a;"}]}}}).itcount();
});