fix(sync-service): Fix bug with logical operators with 3 or more argu…

…ments (#2225)

Fix for #2224

.changeset/stale-bats-tickle.md

@@ -0,0 +1,5 @@
+---
+"@core/sync-service": patch
+---
+
+Fix bug with WHERE clauses with logical operators (AND, OR, etc.) with 3 or more conditions chained together

packages/sync-service/lib/electric/replication/eval/parser.ex

@@ -254,13 +254,15 @@ defmodule Electric.Replication.Eval.Parser do
               :NOT_EXPR -> {&Kernel.not/1, "not"}
             end
 
-          maybe_reduce(%Func{
+          %Func{
             implementation: fun,
             name: name,
             type: :bool,
             args: args,
             location: expr.location
-          })
+          }
+          |> to_binary_operators()
+          |> maybe_reduce()
 
         %{location: loc} = node ->
           {:error, {loc, "#{internal_node_to_error(node)} is not castable to bool"}}
@@ -1120,4 +1122,15 @@ defmodule Electric.Replication.Eval.Parser do
         {:ok, arg}
     end)
   end
+
+  # to_binary_operators/1 coverts a function with more than two arguments to a tree of binary operators
+  defp to_binary_operators(%Func{args: [_, _]} = func) do
+    # The function is already a binary operator (it has two arguments) so just return the function
+    func
+  end
+
+  defp to_binary_operators(%Func{args: [arg | args]} = func) do
+    # The function has more than two arguments, reduce the number of arguments to two: the first argument and a binary operator
+    %Func{func | args: [arg, to_binary_operators(%Func{func | args: args})]}
+  end
 end

packages/sync-service/test/electric/replication/eval/runner_test.exs

@@ -62,6 +62,13 @@ defmodule Electric.Replication.Eval.RunnerTest do
                |> Runner.execute(%{["test"] => "test"})
     end
 
+    test "can evaluate AND expression with multiple conditions" do
+      assert {:ok, true} =
+               ~S|test > 1 AND test = 2 AND test < 3|
+               |> Parser.parse_and_validate_expression!(%{["test"] => :int4})
+               |> Runner.execute(%{["test"] => 2})
+    end
+
     test "should work with array types" do
       assert {:ok, [[1, 2], [3, 4]]} =
                ~S|ARRAY[ARRAY[1, x], ARRAY['3', 2 + 2]]|