1 files changed, 157 insertions, 0 deletions
diff --git a/test/elixir/test/rev_stemming_test.exs b/test/elixir/test/rev_stemming_test.exs
new file mode 100644
index 000000000..9a16d481d
--- /dev/null
+++ b/test/elixir/test/rev_stemming_test.exs
@@ -0,0 +1,157 @@
+defmodule RevStemmingTest do
+  use CouchTestCase
+
+  @moduletag :revs
+
+  @moduledoc """
+  This is a port of the rev_stemming.js suite
+  """
+
+  @new_limit 5
+
+  @tag :with_db
+  test "revs limit update", context do
+    db_name = context[:db_name]
+
+    resp = Couch.get("/#{db_name}/_revs_limit")
+    assert resp.body == 1000
+
+    create_rev_doc(db_name, "foo", @new_limit + 1)
+    resp = Couch.get("/#{db_name}/foo?revs=true")
+    assert length(resp.body["_revisions"]["ids"]) == @new_limit + 1
+
+    resp =
+      Couch.put("/#{db_name}/_revs_limit",
+        body: "#{@new_limit}",
+        headers: ["Content-type": "application/json"]
+      )
+
+    assert resp.status_code == 200
+
+    create_rev_doc(db_name, "foo", @new_limit + 1)
+    resp = Couch.get("/#{db_name}/foo?revs=true")
+    assert length(resp.body["_revisions"]["ids"]) == @new_limit
+  end
+
+  @tag :with_db
+  test "revs limit produces replication conflict ", context do
+    db_name = context[:db_name]
+
+    db_name_b = "#{db_name}_b"
+    create_db(db_name_b)
+    delete_db_on_exit([db_name_b])
+
+    resp =
+      Couch.put("/#{db_name}/_revs_limit",
+        body: "#{@new_limit}",
+        headers: ["Content-type": "application/json"]
+      )
+
+    assert resp.status_code == 200
+
+    create_rev_doc(db_name, "foo", @new_limit + 1)
+    resp = Couch.get("/#{db_name}/foo?revs=true")
+    assert length(resp.body["_revisions"]["ids"]) == @new_limit
+
+    # If you replicate after you make more edits than the limit, you'll
+    # cause a spurious edit conflict.
+    replicate(db_name, db_name_b)
+    resp = Couch.get("/#{db_name_b}/foo?conflicts=true")
+    assert not Map.has_key?(resp.body, "_conflicts")
+
+    create_rev_doc(db_name, "foo", @new_limit - 1)
+
+    # one less edit than limit, no conflict
+    replicate(db_name, db_name_b)
+    resp = Couch.get("/#{db_name_b}/foo?conflicts=true")
+    assert not Map.has_key?(resp.body, "_conflicts")
+    prev_conflicted_rev = resp.body["_rev"]
+
+    # now we hit the limit
+    create_rev_doc(db_name, "foo", @new_limit + 1)
+
+    replicate(db_name, db_name_b)
+    resp = Couch.get("/#{db_name_b}/foo?conflicts=true")
+    assert Map.has_key?(resp.body, "_conflicts")
+
+    conflicted_rev =
+      resp.body["_conflicts"]
+      |> Enum.at(0)
+
+    # we have a conflict, but the previous replicated rev is always the losing
+    # conflict
+    assert conflicted_rev == prev_conflicted_rev
+  end
+
+  @tag :with_db
+  test "revs limit is kept after compaction", context do
+    db_name = context[:db_name]
+
+    create_rev_doc(db_name, "bar", @new_limit + 1)
+    resp = Couch.get("/#{db_name}/bar?revs=true")
+    assert length(resp.body["_revisions"]["ids"]) == @new_limit + 1
+
+    resp =
+      Couch.put("/#{db_name}/_revs_limit",
+        body: "#{@new_limit}",
+        headers: ["Content-type": "application/json"]
+      )
+
+    assert resp.status_code == 200
+
+    # We having already updated bar before setting the limit, so it's still got
+    # a long rev history. compact to stem the revs.
+    resp = Couch.get("/#{db_name}/bar?revs=true")
+    assert length(resp.body["_revisions"]["ids"]) == @new_limit
+
+    compact(db_name)
+
+    # force reload because ETags don't honour compaction
+    resp =
+      Couch.get("/#{db_name}/bar?revs=true",
+        headers: ["if-none-match": "pommes"]
+      )
+
+    assert length(resp.body["_revisions"]["ids"]) == @new_limit
+  end
+
+  # function to create a doc with multiple revisions
+  defp create_rev_doc(db_name, id, num_revs) do
+    resp = Couch.get("/#{db_name}/#{id}")
+
+    doc =
+      if resp.status_code == 200 do
+        resp.body
+      else
+        %{_id: id, count: 0}
+      end
+
+    {:ok, resp} = create_doc(db_name, doc)
+    create_rev_doc(db_name, id, num_revs, [Map.put(doc, :_rev, resp.body["rev"])])
+  end
+
+  defp create_rev_doc(db_name, id, num_revs, revs) do
+    if length(revs) < num_revs do
+      doc = %{_id: id, _rev: Enum.at(revs, -1)[:_rev], count: length(revs)}
+      {:ok, resp} = create_doc(db_name, doc)
+
+      create_rev_doc(
+        db_name,
+        id,
+        num_revs,
+        revs ++ [Map.put(doc, :_rev, resp.body["rev"])]
+      )
+    else
+      revs
+    end
+  end
+
+  def delete_db_on_exit(db_names) when is_list(db_names) do
+    on_exit(fn ->
+      Enum.each(db_names, fn name ->
+        delete_db(name)
+      end)
+    end)
+  end
+
+end