Type if expression properly

1 files changed, 21 insertions, 0 deletions

diff --git a/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerIfTests.java b/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerIfTests.java
index 796dd7c9..47a6cc22 100644
--- a/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerIfTests.java
+++ b/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerIfTests.java
@@ -35,6 +35,27 @@ public class TypeCheckerIfTests {
     }
 
     @Test
+    public void whenBranchesHaveDifferentTypesThenTypeOfIfIsUnionOfBranchTypes() {
+        var untyped = Untyped.if_(
+            List.of(
+                Untyped.conditionalBranch(
+                    Untyped.boolLiteral(true),
+                    Untyped.block(List.of(
+                        Untyped.blockReturn(Untyped.intLiteral(42))
+                    ))
+                )
+            ),
+            Untyped.block(List.of(
+                Untyped.blockReturn(Untyped.stringLiteral("b"))
+            ))
+        );
+
+        var result = TypeChecker.typeCheckExpression(untyped, TypeCheckerContext.EMPTY);
+
+        assertThat(result.value().type(), equalTo(Types.TOP));
+    }
+
+    @Test
     public void whenConditionIsNotBoolThenErrorIsThrown() {
         var untyped = Untyped.if_(
             List.of(