fix: infinite loop parsing incomplete struct

lib/spitfire.ex

@@ -1698,11 +1698,9 @@ defmodule Spitfire do
           {parser, is_valid} = validate_peek(parser, current_token_type(parser))
 
           if is_valid do
-            while peek_token(parser) not in terminals && calc_prec(parser, associativity, precedence) <- {left, parser} do
-              case peek_token_type(parser) do
-                :. -> parse_dot_expression(next_token(parser), left)
-                _ -> {left, parser}
-              end
+            while peek_token(parser) not in terminals && peek_token(parser) == :. &&
+                    calc_prec(parser, associativity, precedence) <- {left, parser} do
+              parse_dot_expression(next_token(parser), left)
             end
           else
             {left, parser}

test/spitfire_test.exs

@@ -2722,6 +2722,16 @@ defmodule SpitfireTest do
                ]
              }
     end
+
+    test "incomplete struct in match expression" do
+      assert Spitfire.parse("%Foo = x") ==
+               {:error,
+                {:%, [line: 1, column: 1],
+                 [
+                   {:__aliases__, [last: [line: 1, column: 2], line: 1, column: 2], [:Foo]},
+                   {:%{}, [closing: [line: 1, column: 8], line: 1, column: 6], [{:x, [line: 1, column: 8], nil}]}
+                 ]}, [{[line: 1, column: 8], "missing closing brace for struct"}]}
+    end
   end
 
   describe "&parse_with_comments/2" do