Allow schema to be used for values list types (#4553)

Author: greg-rychlewski

integration_test/cases/repo.exs

@@ -2207,6 +2207,17 @@ defmodule Ecto.Integration.RepoTest do
       assert TestRepo.all(query) == Enum.map(values, &{&1, &1.bid})
     end
 
+    test "all with schema types" do
+      uuid_module = uuid_module(TestRepo.__adapter__())
+      uuid = uuid_module.generate()
+
+      raw_values = [%{bid: uuid, visits: "1"}, %{bid: uuid, visits: "2"}]
+      casted_values = [%{bid: uuid, visits: 1}, %{bid: uuid, visits: 2}]
+      types = Post
+      query = from v in values(raw_values, types)
+      assert TestRepo.all(query) == casted_values
+    end
+
     test "all with join" do
       uuid_module = uuid_module(TestRepo.__adapter__())
       uuid = uuid_module.generate()

lib/ecto/query.ex

@@ -507,7 +507,7 @@ defmodule Ecto.Query do
       MapSet.to_list(fields)
     end
 
-    defp types!(fields, types) do
+    defp types!(fields, types) when is_map(types) do
       Enum.map(fields, fn field ->
         case types do
           %{^field => type} ->
@@ -521,6 +521,18 @@ defmodule Ecto.Query do
       end)
     end
 
+    defp types!(fields, schema) when is_atom(schema) do
+      Enum.map(fields, fn field ->
+        if type = schema.__schema__(:type, field) do
+          {field, type}
+        else
+          raise ArgumentError,
+                "values/2 must declare the type for every field. " <>
+                  "The type was not given for field `#{field}`"
+        end
+      end)
+    end
+
     defp params!(values_list, types) do
       Enum.reduce(values_list, [], fn values, params ->
         Enum.reduce(types, params, fn {field, type}, params ->

lib/ecto/query/api.ex

@@ -518,13 +518,15 @@ defmodule Ecto.Query.API do
   An error is raised if the list is empty or if every map does not have exactly the
   same fields.
 
-  The second argument is a map of types corresponding to the fields in the first argument.
+  The second argument is either a map of types or an Ecto schema containing all the
+  fields in the first argument.
+
   Each field must be given a type or an error is raised. Any type that can be specified in
   a schema may be used.
 
   Queries using a values list are not cacheable by Ecto.
 
-  ## Select example
+  ## Select with map types example
 
       values = [%{id: 1, text: "abc"}, %{id: 2, text: "xyz"}]
       types = %{id: :integer, text: :string}
@@ -536,6 +538,18 @@ defmodule Ecto.Query.API do
 
       Repo.all(query)
 
+  ## Select with schema types example
+
+      values = [%{id: 1, text: "abc"}, %{id: 2, text: "xyz"}]
+      types = ValuesSchema
+
+      query =
+        from v1 in values(values, types),
+          join: v2 in values(values, types),
+          on: v1.id == v2.id
+
+      Repo.all(query)
+
   ## Delete example
       values = [%{id: 1, text: "abc"}, %{id: 2, text: "xyz"}]
       types = %{id: :integer, text: :string}

test/ecto/query/builder/from_test.exs

@@ -5,6 +5,16 @@ defmodule Ecto.Query.Builder.FromTest do
 
   import Ecto.Query
 
+  defmodule Schema do
+    use Ecto.Schema
+
+    schema "schema" do
+      field :num, :integer
+      field :text, :string
+    end
+  end
+
+
   defmacro from_macro(left, right) do
     quote do
       fragment("? <> ?", unquote(left), unquote(right))
@@ -19,31 +29,52 @@ defmodule Ecto.Query.Builder.FromTest do
   end
 
   test "values list source" do
-    # Valid input
     values = [%{num: 1, text: "one"}, %{num: 2, text: "two"}]
     types = %{num: :integer, text: :string}
     query = from v in values(values, types)
 
     types_kw = Enum.map(types, & &1)
     assert query.from.source == {:values, [], [types_kw, length(values)]}
+  end
+
+  test "values list source with types defined by schema" do
+    values = [%{num: 1, text: "one"}, %{num: 2, text: "two"}]
+    type_schema = Schema
+    types_kw = Enum.map(%{num: :integer, text: :string}, & &1)
+    query = from v in values(values, type_schema)
+
+    assert query.from.source == {:values, [], [types_kw, length(values)]}
+  end
 
-    # Empty values
+  test "values list source with empty values" do
     msg = "must provide a non-empty list to values/2"
 
     assert_raise ArgumentError, msg, fn ->
       from v in values([], %{})
     end
+  end
 
-
-    # Missing type
+  test "values list source with missing types" do
     msg = "values/2 must declare the type for every field. The type was not given for field `text`"
 
     assert_raise ArgumentError, msg, fn ->
       values = [%{num: 1, text: "one"}, %{num: 2, text: "two"}]
       types = %{num: :integer}
       from v in values(values, types)
     end
+  end
+
+  test "values list source with missing schema types" do
+    msg = "values/2 must declare the type for every field. The type was not given for field `not_a_field`"
+
+    assert_raise ArgumentError, msg, fn ->
+      values = [%{not_a_field: 1}]
+      types = Schema
+      from v in values(values, types)
+    end
+  end
 
+  test "values list source with inconsistent fields across entries" do
     # Missing field
     msg = "each member of a values list must have the same fields. Missing field `text` in %{num: 2}"