Add more concurrent write testsadd-concurrent-test-with-intermettent-view-queries

 * `Secondary data tests with updates and queries`: Like the `Secondary data
    tests with updates` but adds intermittent queries while updates are taking
    place.

 * `Secondary data tests with deletes and queries`: Deletes and queries
   intermettently. This one was specifically crafted to trigger the
   `ebtree:lookup_multi/3` error and hopefully other similar ones. The
   retry_until section at the end was added to differentiate between the case
   were we return a partial view and when the view is actually broken and it
   will never "catch up". Once we start returning only completed views, we
   remove that section.

1 files changed, 76 insertions, 0 deletions

diff --git a/test/elixir/test/concurrent_writes_test.exs b/test/elixir/test/concurrent_writes_test.exs
index 397c5e880..8bc33df6f 100644
--- a/test/elixir/test/concurrent_writes_test.exs
+++ b/test/elixir/test/concurrent_writes_test.exs
@@ -72,4 +72,80 @@ defmodule ConcurrentWritesTest do
     assert result == Enum.sum(2..n + 1)
   end
 
+  @tag :with_db
+  test "Secondary data tests with updates and queries", context do
+    n = 120
+    query_every_n = 40
+    db_name = context[:db_name]
+    map_fun = "function(doc) { emit(null, doc.a); }"
+    red_fun = "_sum"
+    ddoc_id = "_design/foo"
+    ddoc = %{:views => %{:foo => %{:map => map_fun, :reduce => red_fun}}}
+    Couch.put("/#{db_name}/#{ddoc_id}", body: ddoc)
+    parent = self()
+    Enum.each(1..n,
+      fn x -> spawn fn ->
+          r = Couch.put("/#{db_name}/doc#{x}", body: %{:a => x})
+          assert r.status_code == 201
+          rev = r.body["rev"]
+          if rem(x, query_every_n) == 0 do
+              r = Couch.get("/#{db_name}/#{ddoc_id}/_view/foo")
+              assert r.status_code == 200
+          end
+          r = Couch.put("/#{db_name}/doc#{x}", body: %{:_rev => rev, :a => x + 1})
+          assert r.status_code == 201
+          send parent, :done
+        end end)
+    Enum.each(1..n, fn _x -> receive do :done -> :done end end)
+    rows = Couch.get("/#{db_name}/#{ddoc_id}/_view/foo").body["rows"]
+    result = hd(rows)["value"]
+    assert result == Enum.sum(2..n + 1)
+  end
+
+  # The following test was specifically crafted to trigger the issue fixed in:
+  # https://github.com/apache/couchdb/commit/ec4b2132918338d893a800a823cf5f12d5b2efd5
+  #
+  @tag :with_db
+  test "Secondary data tests with deletes and queries", context do
+    n = 120
+    query_every_n = 40
+    db_name = context[:db_name]
+    map_fun = "function(doc) { emit(null, doc.a); }"
+    red_fun = "_sum"
+    ddoc_id = "_design/foo"
+    ddoc = %{:views => %{:foo => %{:map => map_fun, :reduce => red_fun}}}
+    Couch.put("/#{db_name}/#{ddoc_id}", body: ddoc)
+    parent = self()
+    Enum.each(1..n,
+      fn x -> spawn fn ->
+          r = Couch.put("/#{db_name}/doc#{x}", body: %{:a => x})
+          assert r.status_code == 201
+          rev = r.body["rev"]
+          :timer.sleep(:rand.uniform(1000))
+          r = Couch.delete("/#{db_name}/doc#{x}?rev=#{rev}")
+          assert r.status_code == 200
+          if rem(x, query_every_n) == 0 do
+              r = Couch.get("/#{db_name}/#{ddoc_id}/_view/foo")
+              assert r.status_code == 200
+          end
+          send parent, :done
+        end end)
+    Enum.each(1..n, fn _x -> receive do :done -> :done end end)
+
+    # Keep trying to query the view for a bit to account for the case when
+    # partial view results can be returned. After the following commits merges
+    # `retry_until` can be removed:
+    # https://github.com/apache/couchdb/pull/3391/commits/5a82664d1b0b58dd6c9fe6a79faa51e89211969e
+    #
+    try do
+        retry_until(fn ->
+            [] == Couch.get("/#{db_name}/#{ddoc_id}/_view/foo").body["rows"]
+        end, 1000, 5000)
+    rescue
+        RuntimeError -> :ok
+    end
+
+    assert [] == Couch.get("/#{db_name}/#{ddoc_id}/_view/foo").body["rows"]
+  end
+
 end