From 39dcbb3f81dfd930af02a98bf6cdb93a31be0b38 Mon Sep 17 00:00:00 2001
From: David Hatch <david.hatch@mongodb.com>
Date: Tue, 26 Jul 2016 11:55:05 -0400
Subject: [PATCH] repo.

---
 repo.js                               | 61 +++++++++++++++++++++++++++++++++++
 src/mongo/db/exec/collection_scan.cpp |  6 ++++
 2 files changed, 67 insertions(+)
 create mode 100644 repo.js

diff --git a/repo.js b/repo.js
new file mode 100644
index 0000000..e7b5265
--- /dev/null
+++ b/repo.js
@@ -0,0 +1,61 @@
+var coll = db.repo;
+coll.drop();
+
+function debug(x) {
+    printjson(x);
+}
+
+coll.save({});
+
+function getOpId(drop) {
+    var inProg = db.currentOp().inprog;
+    debug(inProg);
+    for (var id in inProg) {
+        var op = inProg[id];
+        if (drop) {
+            if (op.query && op.query.drop && op.query.drop == coll.getName()) {
+                return op.opid;
+            }
+        } else {
+            if (op.query && op.query.query && op.query.query.$where && op.ns == (coll + "")) {
+                return op.opid;
+            }
+        }
+    }
+    return null;
+}
+
+db.getSiblingDB('admin').runCommand({configureFailPoint: 'collectionScanYield', mode: {times: 1}});
+db.getSiblingDB('admin').runCommand(
+    {configureFailPoint: 'setYieldAllLocksWait', mode: {times: 2}, data: {waitForMillis: 500}});
+
+var awaitCount = startParallelShell(
+    "print(\"Count thread started\");" + "db.getMongo().getCollection(\"" + (coll + "") + "\")" +
+    ".count( { $where: function() {" + "while( 1 ) { sleep( 1 ); } } } );" +
+    "print(\"Count thread terminating\");");
+countOpId = null;
+assert.soon(function() {
+    countOpId = getOpId(false);
+    return countOpId;
+});
+
+var awaitDrop =
+    startParallelShell("print(\"Drop thread started\");" + "print(\"drop result: \" + " +
+                       "db.getMongo().getCollection(\"" + (coll + "") + "\")" + ".drop() );" +
+                       "print(\"Drop thread terminating\")");
+dropOpId = null;
+assert.soon(function() {
+    dropOpId = getOpId(true);
+    return dropOpId;
+});
+
+db.killOp(dropOpId);
+db.killOp(countOpId);
+
+var exitCode = awaitCount({checkExitSuccess: false});
+assert.neq(0, exitCode, "expected shell to exit abnormally due to JS execution being terminated");
+
+// The drop operation may or may not have been killed.
+awaitDrop({checkExitSuccess: false});
+
+coll.drop();  // in SERVER-1818, this fails
diff --git a/src/mongo/db/exec/collection_scan.cpp b/src/mongo/db/exec/collection_scan.cpp
index 1e1e88e..73bd644 100644
--- a/src/mongo/db/exec/collection_scan.cpp
+++ b/src/mongo/db/exec/collection_scan.cpp
@@ -40,12 +40,14 @@
 #include "mongo/db/exec/working_set_common.h"
 #include "mongo/db/storage/record_fetcher.h"
 #include "mongo/stdx/memory.h"
+#include "mongo/util/fail_point.h"
 #include "mongo/util/fail_point_service.h"
 #include "mongo/util/log.h"
 
 #include "mongo/db/client.h"  // XXX-ERH
 
 namespace mongo {
+MONGO_FP_DECLARE(collectionScanYield);
 
 using std::unique_ptr;
 using std::vector;
@@ -118,6 +120,10 @@ PlanStage::StageState CollectionScan::doWork(WorkingSetID* out) {
             return PlanStage::NEED_TIME;
         }
 
+        if (MONGO_FAIL_POINT(collectionScanYield)) {
+            return PlanStage::NEED_YIELD;
+        }
+
         if (_lastSeenId.isNull() && !_params.start.isNull()) {
             record = _cursor->seekExact(_params.start);
         } else {
-- 
2.8.3