Add handled effect to try body effects

3 files changed, 112 insertions, 3 deletions

diff --git a/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerIsSubEffectTests.java b/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerIsSubEffectTests.java
new file mode 100644
index 00000000..72e0fa32
--- /dev/null
+++ b/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerIsSubEffectTests.java
@@ -0,0 +1,54 @@
+package org.shedlang.compiler.typechecker;
+
+import org.junit.jupiter.api.Test;
+import org.shedlang.compiler.types.Effects;
+import org.shedlang.compiler.types.NamespaceName;
+
+import static org.shedlang.compiler.typechecker.TypeCheckerSubTyping.isSubEffect;
+import static org.zwobble.precisely.AssertThat.assertThat;
+import static org.zwobble.precisely.Matchers.equalTo;
+
+public class TypeCheckerIsSubEffectTests {
+    public static final NamespaceName NAMESPACE_NAME = NamespaceName.of("Example", "Project");
+
+    @Test
+    public void effectsAreSubEffectsOfThemselves() {
+        var effect = Effects.userDefined(NAMESPACE_NAME, "Effect");
+        var context = TypeCheckerContext.EMPTY;
+
+        assertThat(isSubEffect(Effects.IO, Effects.IO, context), equalTo(true));
+        assertThat(isSubEffect(Effects.NONE, Effects.NONE, context), equalTo(true));
+        assertThat(isSubEffect(effect, effect, context), equalTo(true));
+    }
+
+    @Test
+    public void unrelatedEffectsAreNotSubEffects() {
+        var effect1 = Effects.userDefined(NAMESPACE_NAME, "Effect1");
+        var effect2 = Effects.userDefined(NAMESPACE_NAME, "Effect2");
+        var context = TypeCheckerContext.EMPTY;
+
+        assertThat(isSubEffect(effect1, effect2, context), equalTo(false));
+        assertThat(isSubEffect(effect1, Effects.IO, context), equalTo(false));
+        assertThat(isSubEffect(Effects.IO, effect2, context), equalTo(false));
+    }
+
+    @Test
+    public void noneEffectIsSubEffectOfAllEffects() {
+        var effect = Effects.userDefined(NAMESPACE_NAME, "Effect");
+        var context = TypeCheckerContext.EMPTY;
+
+        assertThat(isSubEffect(Effects.NONE, effect, context), equalTo(true));
+        assertThat(isSubEffect(Effects.NONE, Effects.IO, context), equalTo(true));
+        assertThat(isSubEffect(Effects.NONE, Effects.NONE, context), equalTo(true));
+    }
+
+    @Test
+    public void noneEffectIsOnlySuperEffectOfItself() {
+        var effect = Effects.userDefined(NAMESPACE_NAME, "Effect");
+        var context = TypeCheckerContext.EMPTY;
+
+        assertThat(isSubEffect(effect, Effects.NONE, context), equalTo(false));
+        assertThat(isSubEffect(Effects.IO, Effects.NONE, context), equalTo(false));
+        assertThat(isSubEffect(Effects.NONE, Effects.NONE, context), equalTo(true));
+    }
+}
diff --git a/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerTryTests.java b/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerTryTests.java
index 566a93ee..9224c8ff 100644
--- a/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerTryTests.java
+++ b/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerTryTests.java
@@ -49,7 +49,7 @@ public class TypeCheckerTryTests {
 
     @Test
     public void whenEffectIsNotAllowedInExpressionScopeAndIsNotHandledEffectThenEffectIsNotAllowedInBodyScope() {
-        var handledEffect = Effects.userDefined(NAMESPACE_NAME, "HandledEmpty");
+        var handledEffect = Effects.userDefined(NAMESPACE_NAME, "HandledEffect");
         var unexpectedEffect = Effects.userDefined(NAMESPACE_NAME, "UnexpectedEffect");
         var untyped = UntypedTryNode.builder()
             .addBodyStatement(Untyped.expressionStatement(
@@ -75,13 +75,13 @@ public class TypeCheckerTryTests {
             () -> typeCheckExpression(untyped, context)
         );
 
-        assertThat(error.allowed(), equalTo(Effects.NONE));
+        assertThat(error.allowed(), equalTo(handledEffect));
         assertThat(error.actual(), equalTo(unexpectedEffect));
     }
 
     @Test
     public void effectsAllowedInExpressionScopeAreAllowedInBodyScope() {
-        var handledEffect = Effects.userDefined(NAMESPACE_NAME, "HandledEmpty");
+        var handledEffect = Effects.userDefined(NAMESPACE_NAME, "HandledEffect");
         var allowedEffect = Effects.userDefined(NAMESPACE_NAME, "AllowedEffect");
         var untyped = UntypedTryNode.builder()
             .addBodyStatement(Untyped.expressionStatement(
@@ -106,4 +106,31 @@ public class TypeCheckerTryTests {
 
         assertThat(result.value(), isTypedTryNode());
     }
+
+    @Test
+    public void handledEffectIsAllowedInBodyScope() {
+        var handledEffect = Effects.userDefined(NAMESPACE_NAME, "HandledEffect");
+        var untyped = UntypedTryNode.builder()
+            .addBodyStatement(Untyped.expressionStatement(
+                UntypedCallNode.builder()
+                    .withReceiver(Untyped.reference("f"))
+                    .withHasEffects(true)
+                    .build()
+            ))
+            .withHandledEffect(Untyped.typeLevelReference(handledEffect.name()))
+            .build();
+        var context = TypeCheckerContext.EMPTY
+            .enterFunction(
+                P.map(
+                    Map.entry(handledEffect.name(), Variable.defined(Types.effectType(handledEffect), VariableType.CONSTANT)),
+                    Map.entry("f", Variable.defined(FunctionType.builder().withEffect(handledEffect).build(), VariableType.VAL))
+                ),
+                Effects.NONE,
+                Optional.empty()
+            );
+
+        var result = typeCheckExpression(untyped, context);
+
+        assertThat(result.value(), isTypedTryNode());
+    }
 }
diff --git a/src/test/java/org/shedlang/compiler/types/EffectUnionTests.java b/src/test/java/org/shedlang/compiler/types/EffectUnionTests.java
new file mode 100644
index 00000000..9825a354
--- /dev/null
+++ b/src/test/java/org/shedlang/compiler/types/EffectUnionTests.java
@@ -0,0 +1,28 @@
+package org.shedlang.compiler.types;
+
+import org.junit.jupiter.api.Test;
+
+import static org.zwobble.precisely.AssertThat.assertThat;
+import static org.zwobble.precisely.Matchers.equalTo;
+
+public class EffectUnionTests {
+    @Test
+    public void unionOfNoneAndOtherTypeIsOtherType() {
+        var effect = Effects.userDefined(NamespaceName.of("Example"), "Effect");
+
+        assertThat(Effects.union(effect, Effects.NONE), equalTo(effect));
+        assertThat(Effects.union(Effects.NONE, effect), equalTo(effect));
+        assertThat(Effects.union(Effects.NONE, Effects.NONE), equalTo(Effects.NONE));
+    }
+
+    @Test
+    public void effectUnionDescriptionIsBarSeparatedConstituentEffects() {
+        var effect1 = Effects.userDefined(NamespaceName.of("Example1"), "Effect1");
+        var effect2 = Effects.userDefined(NamespaceName.of("Example2"), "Effect2");
+        var union = Effects.union(effect1, effect2);
+
+        var result = union.describe();
+
+        assertThat(result, equalTo("Example1.Effect1 | Example2.Effect2"));
+    }
+}