Do not look for a common supertype if there is only one type in the worklist

2013-08-22 12:13:15 +04:00
parent eeb4aac313
commit 96335b2e71
1 changed files with 2 additions and 1 deletions
@@ -35,8 +35,9 @@ import static org.jetbrains.jet.lang.types.Variance.*;
 public class CommonSupertypes {
    @NotNull
    public static JetType commonSupertype(@NotNull Collection<JetType> types) {
+        assert !types.isEmpty();
        Collection<JetType> typeSet = new HashSet<JetType>(types);
-        assert !typeSet.isEmpty();
+        if (typeSet.size() == 1) return typeSet.iterator().next();

        // If any of the types is nullable, the result must be nullable
        // This also removed Nothing and Nothing? because they are subtypes of everything else