Check that handled effect is user-defined effect

1 files changed, 23 insertions, 0 deletions

diff --git a/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerTryTests.java b/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerTryTests.java
index 9224c8ff..802f4d44 100644
--- a/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerTryTests.java
+++ b/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerTryTests.java
@@ -4,6 +4,7 @@ import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.untyped.Untyped;
 import org.shedlang.compiler.ast.untyped.UntypedCallNode;
 import org.shedlang.compiler.ast.untyped.UntypedTryNode;
+import org.shedlang.compiler.typechecker.errors.NotUserDefinedEffectError;
 import org.shedlang.compiler.typechecker.errors.UnexpectedEffectError;
 import org.shedlang.compiler.types.Effects;
 import org.shedlang.compiler.types.FunctionType;
@@ -133,4 +134,26 @@ public class TypeCheckerTryTests {
 
         assertThat(result.value(), isTypedTryNode());
     }
+
+    @Test
+    public void whenHandledEffectIsNotUserDefinedEffectThenErrorIsThrown() {
+        var untyped = UntypedTryNode.builder()
+            .withHandledEffect(Untyped.typeLevelReference("Io"))
+            .build();
+        var context = TypeCheckerContext.EMPTY
+            .enterFunction(
+                P.map(
+                    Map.entry("Io", Variable.defined(Types.effectType(Effects.IO), VariableType.CONSTANT))
+                ),
+                Effects.NONE,
+                Optional.empty()
+            );
+
+        var error = assertThrows(
+            NotUserDefinedEffectError.class,
+            () -> typeCheckExpression(untyped, context)
+        );
+
+        assertThat(error.effect(), equalTo(Effects.IO));
+    }
 }