1 files changed, 120 insertions, 118 deletions
diff --git a/jstests/sharding/explain_exec_stats_on_shards.js b/jstests/sharding/explain_exec_stats_on_shards.js
index d9c9067f3ef..fa2a21864d8 100644
--- a/jstests/sharding/explain_exec_stats_on_shards.js
+++ b/jstests/sharding/explain_exec_stats_on_shards.js
@@ -1,137 +1,139 @@
 // Tests for the mongos explain command to ensure that the 'executionStats' section of the explain
 // output is populated correctly for each shard.
 (function() {
-    'use strict';
+'use strict';
 
-    // Verifies that the explain output for the given shard contains all expected fields and that
-    // field values match the values specified in the 'expected*' arguments. This function also
-    // updates the 'totals' object which holds accumulated values for certain fields from each
-    // shard.
-    function verifyExecStatsOnShard({explain,
-                                     expectedShardName,
-                                     expectedNReturned,
-                                     expectedKeysExamined,
-                                     expectedDocsExamined,
-                                     totals}) {
-        assert(explain.executionSuccess, tojson(explain));
-        assert.eq(explain.shardName, expectedShardName, tojson(explain));
-        assert.eq(explain.nReturned, expectedNReturned, tojson(explain));
-        assert.gte(explain.executionTimeMillis, 0, tojson(explain));
-        assert.eq(explain.totalKeysExamined, expectedKeysExamined, tojson(explain));
-        assert.eq(explain.totalDocsExamined, expectedDocsExamined, tojson(explain));
-        assert(explain.hasOwnProperty("executionStages"), tojson(explain));
+// Verifies that the explain output for the given shard contains all expected fields and that
+// field values match the values specified in the 'expected*' arguments. This function also
+// updates the 'totals' object which holds accumulated values for certain fields from each
+// shard.
+function verifyExecStatsOnShard({
+    explain,
+    expectedShardName,
+    expectedNReturned,
+    expectedKeysExamined,
+    expectedDocsExamined,
+    totals
+}) {
+    assert(explain.executionSuccess, tojson(explain));
+    assert.eq(explain.shardName, expectedShardName, tojson(explain));
+    assert.eq(explain.nReturned, expectedNReturned, tojson(explain));
+    assert.gte(explain.executionTimeMillis, 0, tojson(explain));
+    assert.eq(explain.totalKeysExamined, expectedKeysExamined, tojson(explain));
+    assert.eq(explain.totalDocsExamined, expectedDocsExamined, tojson(explain));
+    assert(explain.hasOwnProperty("executionStages"), tojson(explain));
 
-        totals.nReturned += explain.nReturned;
-        totals.executionTimeMillis += explain.executionTimeMillis;
-        totals.keysExamined += explain.totalKeysExamined;
-        totals.docsExamined += explain.totalDocsExamined;
-    }
+    totals.nReturned += explain.nReturned;
+    totals.executionTimeMillis += explain.executionTimeMillis;
+    totals.keysExamined += explain.totalKeysExamined;
+    totals.docsExamined += explain.totalDocsExamined;
+}
 
-    // Create a cluster with 2 shards.
-    const numShards = 2;
-    const st = new ShardingTest({shards: numShards});
-    const db = st.s.getDB(`${jsTest.name()}_db`);
+// Create a cluster with 2 shards.
+const numShards = 2;
+const st = new ShardingTest({shards: numShards});
+const db = st.s.getDB(`${jsTest.name()}_db`);
 
-    // Enable sharding on the database and use shard0 as the primary shard.
-    assert.commandWorked(db.adminCommand({enableSharding: db.getName()}));
-    st.ensurePrimaryShard(db.getName(), st.shard0.shardName);
+// Enable sharding on the database and use shard0 as the primary shard.
+assert.commandWorked(db.adminCommand({enableSharding: db.getName()}));
+st.ensurePrimaryShard(db.getName(), st.shard0.shardName);
 
-    // Test that the explain's 'executionStats' section includes all relevant fields for each shard
-    // when the 'explain' command is executed against a sharded collection.
-    (function testExplainExecutionStatsWithShardedCollection() {
-        // Set up a collection, shard on {a:1}, split at {a:4}, and move the {a:4} chunk to shard1.
-        const shardedColl = db.getCollection(`${jsTest.name()}_sharded`);
-        shardedColl.drop();
-        st.shardColl(shardedColl, {a: 1}, {a: 4}, {a: 4});
+// Test that the explain's 'executionStats' section includes all relevant fields for each shard
+// when the 'explain' command is executed against a sharded collection.
+(function testExplainExecutionStatsWithShardedCollection() {
+    // Set up a collection, shard on {a:1}, split at {a:4}, and move the {a:4} chunk to shard1.
+    const shardedColl = db.getCollection(`${jsTest.name()}_sharded`);
+    shardedColl.drop();
+    st.shardColl(shardedColl, {a: 1}, {a: 4}, {a: 4});
 
-        // Put documents on each shard.
-        const numDocs = 10;
-        for (let i = 0; i < numDocs; i++) {
-            assert.commandWorked(shardedColl.insert({_id: i, a: i}));
-        }
-        assert.eq(shardedColl.find().itcount(), numDocs);
+    // Put documents on each shard.
+    const numDocs = 10;
+    for (let i = 0; i < numDocs; i++) {
+        assert.commandWorked(shardedColl.insert({_id: i, a: i}));
+    }
+    assert.eq(shardedColl.find().itcount(), numDocs);
 
-        // Explain the find command and check that all expected explain fields are present in the
-        // output.
-        const explain = shardedColl.find({}).explain("executionStats");
-        assert(explain.hasOwnProperty("executionStats"), tojson(explain));
-        assert(explain.executionStats.hasOwnProperty("executionStages"), tojson(explain));
-        assert(explain.executionStats.executionStages.hasOwnProperty("shards"), tojson(explain));
-        assert.eq(explain.executionStats.executionStages.shards.length, numShards);
+    // Explain the find command and check that all expected explain fields are present in the
+    // output.
+    const explain = shardedColl.find({}).explain("executionStats");
+    assert(explain.hasOwnProperty("executionStats"), tojson(explain));
+    assert(explain.executionStats.hasOwnProperty("executionStages"), tojson(explain));
+    assert(explain.executionStats.executionStages.hasOwnProperty("shards"), tojson(explain));
+    assert.eq(explain.executionStats.executionStages.shards.length, numShards);
 
-        // Verify execution stats on each shards and accumulate totals.
-        const totals = {nReturned: 0, executionTimeMillis: 0, keysExamined: 0, docsExamined: 0};
-        const executionStages = explain.executionStats.executionStages;
-        // Sort the shards array by the 'shardName' to guarantee consistent results, as explain
-        // outputs from the shards may arrive in an arbitrary order.
-        executionStages.shards.sort((a, b) => a.shardName.localeCompare(b.shardName));
-        verifyExecStatsOnShard({
-            explain: executionStages.shards[0],
-            expectedShardName: st.shard0.shardName,
-            expectedNReturned: 4,
-            expectedKeysExamined: 0,
-            expectedDocsExamined: 4,
-            totals: totals
-        });
-        verifyExecStatsOnShard({
-            explain: executionStages.shards[1],
-            expectedShardName: st.shard1.shardName,
-            expectedNReturned: 6,
-            expectedKeysExamined: 0,
-            expectedDocsExamined: 6,
-            totals: totals
-        });
+    // Verify execution stats on each shards and accumulate totals.
+    const totals = {nReturned: 0, executionTimeMillis: 0, keysExamined: 0, docsExamined: 0};
+    const executionStages = explain.executionStats.executionStages;
+    // Sort the shards array by the 'shardName' to guarantee consistent results, as explain
+    // outputs from the shards may arrive in an arbitrary order.
+    executionStages.shards.sort((a, b) => a.shardName.localeCompare(b.shardName));
+    verifyExecStatsOnShard({
+        explain: executionStages.shards[0],
+        expectedShardName: st.shard0.shardName,
+        expectedNReturned: 4,
+        expectedKeysExamined: 0,
+        expectedDocsExamined: 4,
+        totals: totals
+    });
+    verifyExecStatsOnShard({
+        explain: executionStages.shards[1],
+        expectedShardName: st.shard1.shardName,
+        expectedNReturned: 6,
+        expectedKeysExamined: 0,
+        expectedDocsExamined: 6,
+        totals: totals
+    });
 
-        // Ensure that execution stats accumulated across all shards matches the values in the
-        // top-level 'executionStages' section of the explain output.
-        assert.eq(executionStages.nReturned, totals.nReturned, tojson(explain));
-        assert.eq(executionStages.totalChildMillis, totals.executionTimeMillis, tojson(explain));
-        assert.eq(executionStages.totalKeysExamined, totals.keysExamined, tojson(explain));
-        assert.eq(executionStages.totalDocsExamined, totals.docsExamined, tojson(explain));
-    })();
+    // Ensure that execution stats accumulated across all shards matches the values in the
+    // top-level 'executionStages' section of the explain output.
+    assert.eq(executionStages.nReturned, totals.nReturned, tojson(explain));
+    assert.eq(executionStages.totalChildMillis, totals.executionTimeMillis, tojson(explain));
+    assert.eq(executionStages.totalKeysExamined, totals.keysExamined, tojson(explain));
+    assert.eq(executionStages.totalDocsExamined, totals.docsExamined, tojson(explain));
+})();
 
-    // Test that the explain's 'executionStats' section includes all relevant fields when the
-    // 'explain' command is executed against an unsharded collection.
-    (function testExplainExecutionStatsWithUnshardedCollection() {
-        // Setup an unsharded collection.
-        const unshardedColl = db.getCollection(`${jsTest.name()}_unsharded`);
-        unshardedColl.drop();
-        assert.commandWorked(unshardedColl.ensureIndex({a: 1}));
+// Test that the explain's 'executionStats' section includes all relevant fields when the
+// 'explain' command is executed against an unsharded collection.
+(function testExplainExecutionStatsWithUnshardedCollection() {
+    // Setup an unsharded collection.
+    const unshardedColl = db.getCollection(`${jsTest.name()}_unsharded`);
+    unshardedColl.drop();
+    assert.commandWorked(unshardedColl.ensureIndex({a: 1}));
 
-        // Add documents to the collection.
-        const numDocs = 10;
-        for (let i = 0; i < numDocs; i++) {
-            assert.commandWorked(unshardedColl.insert({_id: i, a: i}));
-        }
-        assert.eq(unshardedColl.count(), numDocs);
+    // Add documents to the collection.
+    const numDocs = 10;
+    for (let i = 0; i < numDocs; i++) {
+        assert.commandWorked(unshardedColl.insert({_id: i, a: i}));
+    }
+    assert.eq(unshardedColl.count(), numDocs);
 
-        // Explain the find command and check that all expected explain fields are present in the
-        // output.
-        const explain = unshardedColl.find({}).explain("executionStats");
-        assert(explain.hasOwnProperty("executionStats"), tojson(explain));
-        assert(explain.executionStats.hasOwnProperty("executionStages"), tojson(explain));
-        assert(explain.executionStats.executionStages.hasOwnProperty("shards"), tojson(explain));
-        assert.eq(explain.executionStats.executionStages.shards.length, 1);
+    // Explain the find command and check that all expected explain fields are present in the
+    // output.
+    const explain = unshardedColl.find({}).explain("executionStats");
+    assert(explain.hasOwnProperty("executionStats"), tojson(explain));
+    assert(explain.executionStats.hasOwnProperty("executionStages"), tojson(explain));
+    assert(explain.executionStats.executionStages.hasOwnProperty("shards"), tojson(explain));
+    assert.eq(explain.executionStats.executionStages.shards.length, 1);
 
-        // Verify execution stats on the primary shard and accumulate totals.
-        const totals = {nReturned: 0, executionTimeMillis: 0, keysExamined: 0, docsExamined: 0};
-        const executionStages = explain.executionStats.executionStages;
-        verifyExecStatsOnShard({
-            explain: executionStages.shards[0],
-            expectedShardName: st.shard0.shardName,
-            expectedNReturned: 10,
-            expectedKeysExamined: 0,
-            expectedDocsExamined: 10,
-            totals: totals
-        });
+    // Verify execution stats on the primary shard and accumulate totals.
+    const totals = {nReturned: 0, executionTimeMillis: 0, keysExamined: 0, docsExamined: 0};
+    const executionStages = explain.executionStats.executionStages;
+    verifyExecStatsOnShard({
+        explain: executionStages.shards[0],
+        expectedShardName: st.shard0.shardName,
+        expectedNReturned: 10,
+        expectedKeysExamined: 0,
+        expectedDocsExamined: 10,
+        totals: totals
+    });
 
-        // Ensure that execution stats on the primary shard matches the values in the top-level
-        // 'executionStages' section of the explain output.
-        assert.eq(executionStages.nReturned, totals.nReturned, tojson(explain));
-        assert.eq(executionStages.totalChildMillis, totals.executionTimeMillis, tojson(explain));
-        assert.eq(executionStages.totalKeysExamined, totals.keysExamined, tojson(explain));
-        assert.eq(executionStages.totalDocsExamined, totals.docsExamined, tojson(explain));
-    })();
+    // Ensure that execution stats on the primary shard matches the values in the top-level
+    // 'executionStages' section of the explain output.
+    assert.eq(executionStages.nReturned, totals.nReturned, tojson(explain));
+    assert.eq(executionStages.totalChildMillis, totals.executionTimeMillis, tojson(explain));
+    assert.eq(executionStages.totalKeysExamined, totals.keysExamined, tojson(explain));
+    assert.eq(executionStages.totalDocsExamined, totals.docsExamined, tojson(explain));
+})();
 
-    st.stop();
+st.stop();
 })();