From 1ea043c40fbeccea1447eb930aac532f32ecafa5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?David=20Pavl=C3=ADk?= <david@dpavlik.cz>
Date: Fri, 3 May 2024 18:25:44 +0200
Subject: [PATCH] Use lists:usort/1 instead of lists:uniq/1 on OTP < 25

lists:uniq/1 was introduced in OTP 25.
---
 src/constraints.erl     | 2 +-
 src/gradualizer_lib.erl | 9 ++++++++-
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/constraints.erl b/src/constraints.erl
index 699de889..1c23a17b 100644
--- a/src/constraints.erl
+++ b/src/constraints.erl
@@ -65,7 +65,7 @@ do_combine(Cs1, Cs2, Env) ->
 
 -spec variables(t()) -> [var()].
 variables(#constraints{ upper_bounds = UBounds, lower_bounds = LBounds }) ->
-    lists:uniq(maps:keys(UBounds) ++ maps:keys(LBounds)).
+    gradualizer_lib:uniq(maps:keys(UBounds) ++ maps:keys(LBounds)).
 
 
 %% Checks that all lower bounds are subtypes of respective upper bounds.
diff --git a/src/gradualizer_lib.erl b/src/gradualizer_lib.erl
index 883a3dfb..6be522eb 100644
--- a/src/gradualizer_lib.erl
+++ b/src/gradualizer_lib.erl
@@ -1,7 +1,7 @@
 %% @private
 -module(gradualizer_lib).
 
--export([merge_with/3, top_sort/1, get_type_definition/3,
+-export([merge_with/3, uniq/1, top_sort/1, get_type_definition/3,
          pick_values/2, fold_ast/3, get_ast_children/1,
          empty_tenv/0, create_tenv/3,
          remove_pos_typed_record_field/1,
@@ -45,6 +45,13 @@ merge_with(F, M1, M2) ->
     end.
 -endif.
 
+-spec uniq([A]) -> [A].
+-if(?OTP_RELEASE >= 25).
+uniq(List) -> lists:uniq(List).
+-else.
+uniq(List) -> lists:usort(List).
+-endif.
+
 %% -- Topological sort
 
 -type graph(Node) :: #{Node => [Node]}. %% List of incoming edges (dependencies).