From c98bc9500646d0991081caab1e10b946fd857bae Mon Sep 17 00:00:00 2001
From: Gareth Bowen <gareth@bowenwebdesign.co.nz>
Date: Tue, 10 May 2016 14:12:53 +1200
Subject: [PATCH] (#5145) - Update checkpoint even when no changes

---
 src/replicate/replicate.js            | 34 +++++++++++++++++++--------
 tests/integration/test.replication.js | 29 +++++++++++++++++++++++
 2 files changed, 53 insertions(+), 10 deletions(-)

diff --git a/src/replicate/replicate.js b/src/replicate/replicate.js
index a1a84d9854..01d6a72d82 100644
--- a/src/replicate/replicate.js
+++ b/src/replicate/replicate.js
@@ -121,11 +121,7 @@ function replicate(src, target, opts, returnValue, result) {
       }
       currentBatch = undefined;
       getChanges();
-    }).catch(function (err) {
-      writingCheckpoint = false;
-      abortReplication('writeCheckpoint completed with error', err);
-      throw err;
-    });
+    }).catch(onCheckpointError);
   }
 
   function getDiffs() {
@@ -294,15 +290,33 @@ function replicate(src, target, opts, returnValue, result) {
     if (changes.results.length > 0) {
       changesOpts.since = changes.last_seq;
       getChanges();
+      processPendingBatch(true);
     } else {
-      if (continuous) {
-        changesOpts.live = true;
-        getChanges();
+
+      var complete = function() {
+        if (continuous) {
+          changesOpts.live = true;
+          getChanges();
+        } else {
+          changesCompleted = true;
+        }
+        processPendingBatch(true);
+      };
+
+      // update the checkpoint so we start from the right seq next time
+      if (!currentBatch && changes.last_seq > last_seq) {
+        writingCheckpoint = true;
+        checkpointer.writeCheckpoint(changes.last_seq,
+            session).then(function () {
+          writingCheckpoint = false;
+          result.last_seq = last_seq = changes.last_seq;
+          complete();
+        })
+        .catch(onCheckpointError);
       } else {
-        changesCompleted = true;
+        complete();
       }
     }
-    processPendingBatch(true);
   }
 
 
diff --git a/tests/integration/test.replication.js b/tests/integration/test.replication.js
index 37d5cf4fc5..1a05f01f9a 100644
--- a/tests/integration/test.replication.js
+++ b/tests/integration/test.replication.js
@@ -1548,6 +1548,35 @@ adapters.forEach(function (adapters) {
       });
     });
 
+    it('Empty replication updates checkpoint (#5145)',
+       function (done) {
+      var db = new PouchDB(dbs.name);
+      var remote = new PouchDB(dbs.remote);
+      var docs1 = [ {_id: '0', integer: 0} ];
+      remote.bulkDocs({ docs: docs1 }, function () {
+        var filter = function () {
+          return false;
+        };
+        db.replicate.from(remote, {
+          filter: filter
+        }, function (err, result) {
+          result.ok.should.equal(true);
+          result.docs_written.should.equal(0);
+          result.docs_read.should.equal(0);
+          result.last_seq.should.equal(1);
+          db.replicate.from(remote, {
+            filter: filter
+          }, function (err, result) {
+            result.ok.should.equal(true);
+            result.docs_written.should.equal(0);
+            result.docs_read.should.equal(0);
+            result.last_seq.should.equal(1);
+            done();
+          });
+        });
+      });
+    });
+
     it('Replication with deleted doc', function (done) {
       var db = new PouchDB(dbs.name);
       var remote = new PouchDB(dbs.remote);