Skip to content

Fix Map.from_struct/1 typecheck #15610

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
josevalim merged 2 commits into from
Jul 14, 2026
+20 −12
Merged

Fix Map.from_struct/1 typecheck #15610

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
4da44bb
Fix Map.from_struct/1 typecheck
AlexGx Jul 14, 2026
d61719b
Apply suggestion from @josevalim
josevalim Jul 14, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
20 changes: 14 additions & 6 deletions lib/elixir/lib/module/types/apply.ex
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -254,7 +254,7 @@ defmodule Module.Types.Apply do
{Map, :fetch,
[{[open_map(), term()], tuple([atom([:ok]), term()]) |> opt_union(atom([:error]))}]},
{Map, :fetch!, [{[open_map(), term()], term()}]},
{Map, :from_struct, [{[open_map()], open_map(__struct__: not_set())}]},
{Map, :from_struct, [{[open_map(__struct__: atom())], open_map(__struct__: not_set())}]},
{Map, :get, [{[open_map(), term()], term()}]},
{Map, :get, [{[open_map(), term(), term()], term()}]},
{Map, :get_lazy, [{[open_map(), term(), fun(0)], term()}]},
Expand Down Expand Up @@ -1129,11 +1129,19 @@ defmodule Module.Types.Apply do
@struct_key atom([:__struct__])
@nil_atom atom([nil])

defp remote_apply(Map, :from_struct, _info, [map] = args_types, stack) do
case map_update(map, @struct_key, not_set(), false, true) do
{_value, descr, _errors} -> {:ok, return(descr, args_types, stack)}
:badmap -> {:error, badremote(Map, :from_struct, args_types)}
{:error, _errors} -> {:ok, map}
defp remote_apply(Map, :from_struct, info, [map] = args_types, stack) do
case remote_apply(info, args_types, stack) do
{:ok, _type} ->
case map_update(map, @struct_key, not_set(), false, true) do
{_value, descr, _errors} ->
{:ok, return(descr, args_types, stack)}

_ ->
{:error, badremote(Map, :from_struct, args_types)}
end

other ->
other
end
end

Expand Down
12 changes: 6 additions & 6 deletions lib/elixir/test/elixir/module/types/map_test.exs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -330,11 +330,8 @@ defmodule Module.Types.MapTest do

describe "Map.from_struct/1" do
test "checking" do
assert typecheck!(Map.from_struct(%{})) ==
empty_map()

assert typecheck!(Map.from_struct(%{key: 123})) ==
closed_map(key: integer())
assert typecheck!(Map.from_struct(%{__struct__: URI, port: 433})) ==
closed_map(port: integer())

assert typecheck!(Map.from_struct(%URI{})) ==
closed_map(
Expand All @@ -359,12 +356,15 @@ defmodule Module.Types.MapTest do
_ = Map.from_struct(x)
x
)
) == dynamic(open_map())
) == dynamic(open_map(__struct__: atom()))
end

test "errors" do
assert typeerror!([x = []], Map.from_struct(x)) =~
"incompatible types given to Map.from_struct/1"

assert typeerror!(Map.from_struct(%{})) =~
"incompatible types given to Map.from_struct/1"
end
end

Expand Down
Loading