Keep literals in insert_all, closes #348

Author: josevalim

lib/ecto/query/planner.ex

@@ -926,14 +926,15 @@ defmodule Ecto.Query.Planner do
     query
     |> normalize_query(operation, adapter, counter)
     |> elem(0)
-    |> normalize_select(keep_literals?(query))
+    |> normalize_select(keep_literals?(operation, query))
   rescue
     e ->
       # Reraise errors so we ignore the planner inner stacktrace
       filter_and_reraise e, __STACKTRACE__
   end
 
-  defp keep_literals?(%{combinations: combinations}), do: combinations != []
+  defp keep_literals?(:insert_all, _), do: true
+  defp keep_literals?(_, %{combinations: combinations}), do: combinations != []
 
   defp normalize_query(query, operation, adapter, counter) do
     case operation do

test/ecto/repo_test.exs

@@ -532,6 +532,26 @@ defmodule Ecto.RepoTest do
       assert ["one", "two", "ten"] = params
     end
 
+    test "takes query as datasource with literals" do
+      import Ecto.Query
+
+      threshold = "ten"
+
+      query = from s in MySchema,
+        where: s.x > ^threshold,
+        select: %{
+          foo: s.x,
+          bar: "bar",
+          baz: nil
+        }
+
+      TestRepo.insert_all(MySchema, query)
+
+      assert_received {:insert_all, %{source: "my_schema"}, {%Ecto.Query{} = query, params}}
+      assert [{{:., _, [{:&, [], [0]}, :x]}, _, []}, "bar", nil] = query.select.fields
+      assert ["ten"] = params
+    end
+
     test "raises when a bad query is given as source" do
       assert_raise ArgumentError, fn ->
         TestRepo.insert_all(MySchema, from(s in MySchema))