SERVER-8514 return error on invalid count query on empty collection

Closes #783

Signed-off-by: Benety Goh <benety@mongodb.com>

1 files changed, 26 insertions, 0 deletions

diff --git a/jstests/core/count11.js b/jstests/core/count11.js
new file mode 100644
index 00000000000..14392b9d90c
--- /dev/null
+++ b/jstests/core/count11.js
@@ -0,0 +1,26 @@
+// SERVER-8514: Test the count command returns an error to the user when given an invalid query
+// predicate, even when the collection doesn't exist.
+
+var t = db.count11;
+
+t.drop();
+
+var validQuery = {a: 1};
+var invalidQuery = {a: {$invalid: 1}};
+
+// Query non-existing collection with empty query.
+assert.eq(0, t.find().count());
+assert.eq(0, t.find().itcount());
+
+// Query non-existing collection.
+// Returns 0 on valid syntax query.
+// Fails on invalid syntax query.
+assert.eq(0, t.find(validQuery).count());
+assert.throws(function() { t.find(invalidQuery).count(); });
+
+// Query existing collection.
+// Returns 0 on valid syntax query.
+// Fails on invalid syntax query.
+assert.commandWorked(db.createCollection(t.getName()));
+assert.eq(0, t.find(validQuery).count());
+assert.throws(function() { t.find(invalidQuery).count(); });