1 files changed, 135 insertions, 0 deletions
diff --git a/jstests/aggregation/testshard1.js b/jstests/aggregation/testshard1.js
new file mode 100644
index 00000000000..3bd0ff5f1bf
--- /dev/null
+++ b/jstests/aggregation/testshard1.js
@@ -0,0 +1,135 @@
+/*
+> ShardingTest
+function (testName, numShards, verboseLevel, numMongos, otherParams) {
+*/
+var shardedAggTest = new ShardingTest({
+    shards: 2,
+    verbose: 1,
+    mongos: 1,
+    other: { chunksize: 1}
+    }
+);
+
+shardedAggTest.adminCommand( { enablesharding : "aggShard" } );
+db = shardedAggTest.getDB( "aggShard" );
+
+/* make sure its cleaned up */
+db.ts1.drop();
+
+shardedAggTest.adminCommand( { shardcollection : "aggShard.ts1", key : { "_id" : 1 } } );
+
+
+/*
+Test combining results in mongos for operations that sub-aggregate on shards.
+
+The unusual operators here are $avg, $pushToSet, $push.   In the case of $avg,
+the shard pipeline produces an object with the current subtotal and item count
+so that these can be combined in mongos by totalling the subtotals counts
+before performing the final division.  For $pushToSet and $push, the shard
+pipelines produce arrays, but in mongos these are combined rather than simply
+being added as arrays within arrays.
+*/
+
+var count = 0;
+var strings = [
+    "one",
+    "two",
+    "three",
+    "four",
+    "five",
+    "six",
+    "seven",
+    "eight",
+    "nine",
+    "ten",
+    "eleven",
+    "twelve",
+    "thirteen",
+    "fourteen",
+    "fifteen",
+    "sixteen",
+    "seventeen",
+    "eighteen",
+    "nineteen",
+    "twenty"
+];
+
+var nItems = 200000;
+for(i = 1; i <= nItems; ++i) {
+    db.ts1.save(
+        {counter: ++count, number: strings[i % 20],
+         filler: "0123456789012345678901234567890123456789"});
+}
+
+// wait for all writebacks to be applied
+assert.eq(db.getLastError(), null);
+
+// a project and group in shards, result combined in mongos
+var a1 = db.runCommand({ aggregate:"ts1", pipeline:[
+    { $project: {
+        cMod10: {$mod:["$counter", 10]},
+        number: 1,
+        counter: 1
+    }},
+    { $group: {
+        _id: "$cMod10",
+        numberSet: {$addToSet: "$number"},
+        avgCounter: {$avg: "$cMod10"}
+    }},
+    { $sort: {_id:1} }
+]});
+
+var a1result = a1.result;
+for(i = 0 ; i < 10; ++i) {
+    assert.eq(a1result[i].avgCounter, a1result[i]._id,
+           'agg sharded test avgCounter failed');
+    assert.eq(a1result[i].numberSet.length, 2,
+           'agg sharded test numberSet length failed');
+}
+
+// an initial group starts the group in the shards, and combines them in mongos
+var a2 = db.runCommand({ aggregate:"ts1", pipeline:[
+    { $group: {
+        _id: "all",
+        total: {$sum: "$counter"}
+    }}
+]});
+
+// sum of an arithmetic progression S(n) = (n/2)(a(1) + a(n));
+assert.eq(a2.result[0].total, (nItems/2)*(1 + nItems),
+       'agg sharded test counter sum failed');
+
+// an initial group starts the group in the shards, and combines them in mongos
+var a3 = db.runCommand({ aggregate:"ts1", pipeline:[
+    { $group: {
+        _id: "$number",
+        total: {$sum: 1}
+    }},
+    { $sort: {_id:1} }
+]});
+
+var a3result = a3.result;
+for(i = 0 ; i < strings.length; ++i) {
+    assert.eq(a3result[i].total, nItems/strings.length,
+           'agg sharded test sum numbers failed');
+}
+
+// a match takes place in the shards; just returning the results from mongos
+var a4 = db.runCommand({ aggregate:"ts1", pipeline:[
+    { $match: {$or:[{counter:55}, {counter:1111},
+                    {counter: 2222}, {counter: 33333},
+                    {counter: 99999}, {counter: 55555}]}
+    }
+]});
+
+var a4result = a4.result;
+for(i = 0; i < 6; ++i) {
+    c = a4result[i].counter;
+    printjson({c:c})
+    assert((c == 55) || (c == 1111) || (c == 2222) ||
+           (c == 33333) || (c = 99999) || (c == 55555),
+           'agg sharded test simple match failed');
+}
+
+// shut everything down
+shardedAggTest.stop();