1 files changed, 98 insertions, 0 deletions
diff --git a/jstests/noPassthrough/initial_sync_same_index_spec.js b/jstests/noPassthrough/initial_sync_same_index_spec.js
new file mode 100644
index 00000000000..5746a6091b3
--- /dev/null
+++ b/jstests/noPassthrough/initial_sync_same_index_spec.js
@@ -0,0 +1,98 @@
+/**
+ * Test that initial sync does not fail if an identical index spec is created, dropped and
+ * recreated.
+ */
+
+(function() {
+"use strict";
+
+load("jstests/libs/fail_point_util.js");  // for kDefaultWaitForFailPointTimeout
+
+const testName = "initial_sync_same_index_spec";
+const dbName = testName;
+const collName = "testcoll";
+
+// Set up a stable two node replica set.
+let replTest = new ReplSetTest({
+    name: testName,
+    nodes: [{}, {rsConfig: {priority: 0, votes: 0}}],
+});
+replTest.startSet();
+replTest.initiateWithHighElectionTimeout();
+
+let primary = replTest.getPrimary();
+let secondary = replTest.getSecondary();
+
+let primaryDB = primary.getDB(dbName);
+let secondaryDB = secondary.getDB(dbName);
+
+let primaryColl = primaryDB[collName];
+let secondaryColl = secondaryDB[collName];
+
+// Insert data into the collection for initial sync to copy.
+assert.commandWorked(primaryColl.insert([{_id: 1, a: 1}, {_id: 2, a: 2}]));
+
+// Set WC to 1. The default WC is majority and the replica set will not be able to satisfy majority
+// index create/drop later.
+assert.commandWorked(primary.adminCommand(
+    {setDefaultRWConcern: 1, defaultWriteConcern: {w: 1}, writeConcern: {w: "majority"}}));
+
+/**
+ * Restart the the secondary with no data in order to provoke an initial sync from the primary.
+ * Use startup setParameter to set failpoints to pause the initial sync before indexes are fetched.
+ */
+
+const fp = 'hangBeforeClonerStage';
+let secondaryStartupParams = {};
+secondaryStartupParams['failpoint.' + fp] = tojson({
+    mode: 'alwaysOn',
+    data: {cloner: "CollectionCloner", stage: "listIndexes", nss: primaryColl.getFullName()}
+});
+
+// Only try initial sync once, so any failure syncing indexes will be surfaced.
+secondaryStartupParams['numInitialSyncAttempts'] = 1;
+
+const startupOptions = {
+    startClean: true,
+    setParameter: secondaryStartupParams
+};
+
+jsTestLog(
+    "Restarting the the secondary with no data in order to provoke an initial sync from the " +
+    "primary. Using startup options: " + tojson(startupOptions));
+secondary = replTest.restart(secondary, startupOptions);
+secondaryDB = secondary.getDB(dbName);
+secondaryColl = secondaryDB[collName];
+
+jsTestLog("Waiting for secondary to reach failPoint '" + fp + "'");
+assert.commandWorked(secondary.adminCommand(
+    {waitForFailPoint: fp, timesEntered: 1, maxTimeMS: kDefaultWaitForFailPointTimeout}));
+
+// Restarting the secondary may have resulted in an election.  Wait until the system stabilizes and
+// reaches RS_STARTUP2 state.
+replTest.getPrimary();
+replTest.waitForState(secondary, ReplSetTest.State.STARTUP_2);
+
+/**
+ * Now that the secondary is hanging in initial sync, create, drop and recreate identical indexes to
+ * ensure it is correctly handled by initial sync (when the failpoint is removed).
+ */
+
+jsTestLog("Creating index on the primary.");
+assert.commandWorked(primaryColl.createIndex({a: 1}, {name: "a1"}));
+
+jsTestLog("Dropping index on the primary.");
+assert.commandWorked(primaryColl.dropIndex("a1"));
+
+jsTestLog("Recreating index with same spec on the primary.");
+assert.commandWorked(primaryColl.createIndex({a: 1}, {name: "a2"}));
+
+jsTestLog("Allowing secondary initial sync to resume.");
+assert.commandWorked(
+    secondary.adminCommand({configureFailPoint: "hangBeforeClonerStage", mode: 'off'}));
+
+jsTestLog("Waiting for initial sync to complete successfully.");
+replTest.waitForState(secondary, ReplSetTest.State.SECONDARY);
+
+replTest.stopSet();
+})();