allow fragment tuple sources

Author: greg-rychlewski

integration_test/sql/sql.exs

@@ -7,7 +7,12 @@ defmodule Ecto.Integration.SQLTest do
   alias Ecto.Integration.Post
   alias Ecto.Integration.CorruptedPk
   alias Ecto.Integration.Tag
-  import Ecto.Query, only: [from: 2]
+  import Ecto.Query, only: [from: 2, from: 1]
+
+  test "fragment tuple sources" do
+    query = from f in {fragment("select 1 as num"), Barebone}
+    assert %Barebone{num: 1} = TestRepo.one(query)
+  end
 
   test "fragmented types" do
     datetime = ~N[2014-01-16 20:26:51]

lib/ecto/adapters/myxql/connection.ex

@@ -735,11 +735,11 @@ if Code.ensure_loaded?(MyXQL) do
     end
 
     defp expr({:fragment, _, parts}, sources, query) do
-      Enum.map(parts, fn
-        {:raw, part} -> part
-        {:expr, expr} -> expr(expr, sources, query)
-      end)
-      |> parens_for_select
+      fragment_expr(parts, sources, query)
+    end
+
+    defp expr({{:fragment, _, parts}, schema}, sources, query) when is_atom(schema) do
+      fragment_expr(parts, sources, query)
     end
 
     defp expr({:values, _, [types, _idx, num_rows]}, _, query) do
@@ -911,6 +911,14 @@ if Code.ensure_loaded?(MyXQL) do
       end)
     end
 
+    defp fragment_expr(parts, sources, query) do
+      Enum.map(parts, fn
+        {:raw, part} -> part
+        {:expr, expr} -> expr(expr, sources, query)
+      end)
+      |> parens_for_select()
+    end
+
     defp interval(count, "millisecond", sources, query) do
       ["INTERVAL (", expr(count, sources, query) | " * 1000) microsecond"]
     end
@@ -949,6 +957,9 @@ if Code.ensure_loaded?(MyXQL) do
         {:fragment, _, _} ->
           {nil, as_prefix ++ [?f | Integer.to_string(pos)], nil}
 
+        {{:fragment, _, _}, schema, _} ->
+          {nil, as_prefix ++ [?f | Integer.to_string(pos)], schema}
+
         {:values, _, _} ->
           {nil, as_prefix ++ [?v | Integer.to_string(pos)], nil}
 

lib/ecto/adapters/postgres/connection.ex

@@ -974,11 +974,11 @@ if Code.ensure_loaded?(Postgrex) do
     end
 
     defp expr({:fragment, _, parts}, sources, query) do
-      Enum.map(parts, fn
-        {:raw, part} -> part
-        {:expr, expr} -> expr(expr, sources, query)
-      end)
-      |> parens_for_select
+      fragment_expr(parts, sources, query)
+    end
+
+    defp expr({{:fragment, _, parts}, schema}, sources, query) when is_atom(schema) do
+      fragment_expr(parts, sources, query)
     end
 
     defp expr({:values, _, [types, idx, num_rows]}, _, _query) do
@@ -1162,6 +1162,14 @@ if Code.ensure_loaded?(Postgrex) do
       end)
     end
 
+    defp fragment_expr(parts, sources, query) do
+      Enum.map(parts, fn
+        {:raw, part} -> part
+        {:expr, expr} -> expr(expr, sources, query)
+      end)
+      |> parens_for_select()
+    end
+
     defp type_unless_typed(%Ecto.Query.Tagged{}, _type), do: []
     defp type_unless_typed(_, type), do: [?:, ?: | type]
 
@@ -1226,6 +1234,9 @@ if Code.ensure_loaded?(Postgrex) do
         {:fragment, _, _} ->
           {nil, as_prefix ++ [?f | Integer.to_string(pos)], nil}
 
+        {{:fragment, _, _}, schema, _} ->
+          {nil, as_prefix ++ [?f | Integer.to_string(pos)], schema}
+
         {:values, _, _} ->
           {nil, as_prefix ++ [?v | Integer.to_string(pos)], nil}
 

lib/ecto/adapters/tds/connection.ex

@@ -815,11 +815,11 @@ if Code.ensure_loaded?(Tds) do
     end
 
     defp expr({:fragment, _, parts}, sources, query) do
-      Enum.map(parts, fn
-        {:raw, part} -> part
-        {:expr, expr} -> expr(expr, sources, query)
-      end)
-      |> parens_for_select
+      fragment_expr(parts, sources, query)
+    end
+
+    defp expr({{:fragment, _, parts}, schema}, sources, query) when is_atom(schema) do
+      fragment_expr(parts, sources, query)
     end
 
     defp expr({:values, _, [types, idx, num_rows]}, _, _query) do
@@ -1007,6 +1007,14 @@ if Code.ensure_loaded?(Tds) do
       end)
     end
 
+    defp fragment_expr(parts, sources, query) do
+      Enum.map(parts, fn
+        {:raw, part} -> part
+        {:expr, expr} -> expr(expr, sources, query)
+      end)
+      |> parens_for_select()
+    end
+
     defp op_to_binary({op, _, [_, _]} = expr, sources, query) when op in @binary_ops do
       paren_expr(expr, sources, query)
     end
@@ -1070,6 +1078,9 @@ if Code.ensure_loaded?(Tds) do
         {:fragment, _, _} ->
           {nil, as_prefix ++ [?f | Integer.to_string(pos)], nil}
 
+        {{:fragment, _, _}, schema, _} ->
+          {nil, as_prefix ++ [?f | Integer.to_string(pos)], schema}
+
         {:values, _, _} ->
           {nil, as_prefix ++ [?v | Integer.to_string(pos)], nil}