(function() {

var s = new ShardingTest({name: "presplit", shards: 2, mongos: 1, other: {chunkSize: 1}});

s.adminCommand({enablesharding: "test"});
s.ensurePrimaryShard('test', s.shard1.shardName);

// Insert enough data in 'test.foo' to fill several chunks, if it was sharded.
bigString = "";
while (bigString.length < 10000) {
    bigString += "asdasdasdasdadasdasdasdasdasdasdasdasda";
}

db = s.getDB("test");
inserted = 0;
num = 0;
var bulk = db.foo.initializeUnorderedBulkOp();
while (inserted < (20 * 1024 * 1024)) {
    bulk.insert({_id: num++, s: bigString});
    inserted += bigString.length;
}
assert.commandWorked(bulk.execute());

// Make sure that there's only one chunk holding all the data.
s.printChunks();
primary = s.getPrimaryShard("test").getDB("test");
assert.eq(0, s.config.chunks.count({"ns": "test.foo"}), "single chunk assertion");
assert.eq(num, primary.foo.count());

s.adminCommand({shardcollection: "test.foo", key: {_id: 1}});

// Make sure the collection's original chunk got split
s.printChunks();
assert.lt(20, s.config.chunks.count({"ns": "test.foo"}), "many chunks assertion");
assert.eq(num, primary.foo.count());

s.printChangeLog();
s.stop();
})();