From 6d7a1f9fe2029e1bc507d27413274284ac06d582 Mon Sep 17 00:00:00 2001
From: Gaith Hallak <gaithhallak@gmail.com>
Date: Sat, 4 Dec 2021 18:14:05 +0200
Subject: [PATCH] Solve named argument constraints when record type
 dereferencing fails

---
 src/aeso_ast_infer_types.erl                  | 24 +++++++++++++++----
 test/aeso_compiler_tests.erl                  |  1 +
 .../remote_call_ambiguous_record.aes          | 11 +++++++++
 3 files changed, 31 insertions(+), 5 deletions(-)
 create mode 100644 test/contracts/remote_call_ambiguous_record.aes

diff --git a/src/aeso_ast_infer_types.erl b/src/aeso_ast_infer_types.erl
index 11d970e..b34d005 100644
--- a/src/aeso_ast_infer_types.erl
+++ b/src/aeso_ast_infer_types.erl
@@ -2322,7 +2322,8 @@ solve_field_constraints(Env, Constraints) ->
 
 -spec solve_ambiguous_field_constraints(env(), [field_constraint()]) -> ok.
 solve_ambiguous_field_constraints(Env, Constraints) ->
-    Unknown = solve_known_record_types(Env, Constraints),
+    NamedArgConstraints = get_named_argument_constraints(),
+    Unknown = solve_known_record_types(Env, Constraints, NamedArgConstraints),
     if Unknown == [] -> ok;
        length(Unknown) < length(Constraints) ->
             %% progress! Keep trying.
@@ -2347,10 +2348,23 @@ solve_unknown_record_types(Env, Unknown) ->
         false -> Solutions
     end.
 
--spec solve_known_record_types(env(), [field_constraint()]) -> [field_constraint()].
-solve_known_record_types(Env, Constraints) ->
+%% Since named argument constraints solving happens after field
+%% constraints solving, try to find if dereferencing a record type
+%% is failing due to unsolved named argument constraint
+dereference_or_solve_named_argument_constraints(Env, RecType, Cs) ->
+    case dereference(RecType) of
+        UVar = {uvar, _, R} ->
+            L = [DT || DT = #dependent_type_constraint{specialized_type = {uvar, _, STR}} <- Cs, STR == R],
+            solve_named_argument_constraints(Env, L),
+            dereference(UVar);
+        Type ->
+            Type
+    end.
+
+-spec solve_known_record_types(env(), [field_constraint()], [named_argument_constraint()]) -> [field_constraint()].
+solve_known_record_types(Env, Constraints, NamedArgConstraints) ->
     DerefConstraints =
-        [ C#field_constraint{record_t = dereference(RecordType)}
+        [ C#field_constraint{record_t = dereference_or_solve_named_argument_constraints(Env, RecordType,  NamedArgConstraints)}
          || C = #field_constraint{record_t = RecordType} <- Constraints ],
     SolvedConstraints =
         [begin
@@ -2398,7 +2412,7 @@ destroy_and_report_unsolved_field_constraints(Env) ->
                         OtherCs),
     {ContractCs, []} =
         lists:partition(fun(#is_contract_constraint{}) -> true; (_) -> false end, OtherCs1),
-    Unknown  = solve_known_record_types(Env, FieldCs),
+    Unknown  = solve_known_record_types(Env, FieldCs, []),
     if Unknown == [] -> ok;
        true ->
             case solve_unknown_record_types(Env, Unknown) of
diff --git a/test/aeso_compiler_tests.erl b/test/aeso_compiler_tests.erl
index 26a0c74..e5e646f 100644
--- a/test/aeso_compiler_tests.erl
+++ b/test/aeso_compiler_tests.erl
@@ -168,6 +168,7 @@ compilable_contracts() ->
      "maps",
      "oracles",
      "remote_call",
+     "remote_call_ambiguous_record",
      "simple",
      "simple_storage",
      "spend_test",
diff --git a/test/contracts/remote_call_ambiguous_record.aes b/test/contracts/remote_call_ambiguous_record.aes
new file mode 100644
index 0000000..915045f
--- /dev/null
+++ b/test/contracts/remote_call_ambiguous_record.aes
@@ -0,0 +1,11 @@
+contract interface Coin =
+    entrypoint mint : () => int
+
+contract interface OtherCoin =
+    entrypoint mint : () => int
+
+main contract Main =
+    function mkCoin() : Coin = ct_11111111111111111111111111111115rHyByZ
+    entrypoint foo() : int =
+        let r = mkCoin()
+        r.mint()