Handle Box and Shared when determining constructibility

1 files changed, 109 insertions, 1 deletions

diff --git a/src/test/java/org/zwobble/hobgoblin/compiler/analysis/ArbitraryValueAnalysisTests.java b/src/test/java/org/zwobble/hobgoblin/compiler/analysis/ArbitraryValueAnalysisTests.java
index 526f6bb..b802386 100644
--- a/src/test/java/org/zwobble/hobgoblin/compiler/analysis/ArbitraryValueAnalysisTests.java
+++ b/src/test/java/org/zwobble/hobgoblin/compiler/analysis/ArbitraryValueAnalysisTests.java
@@ -57,7 +57,7 @@ public class ArbitraryValueAnalysisTests {
     }
 
     @Test
-    public void firstNonRecursiveVariantIsChosen() {
+    public void firstNonRecursivelyConstructibleVariantIsChosen() {
         var sumType = new SumType(NamespaceName.of(), "X");
         var recursiveVariantType = new StructType(NamespaceName.of(), "Y");
         var nonRecursiveVariantType = new StructType(NamespaceName.of(), "Z");
@@ -82,4 +82,112 @@ public class ArbitraryValueAnalysisTests {
 
         assertThat(variant, equalTo(nonRecursiveVariantType));
     }
+
+    @Test
+    public void boxIsRecursivelyConstructibleIffInnerTypeIsRecursivelyConstructible() {
+        var sumType = new SumType(NamespaceName.of(), "X");
+        var recursiveVariantType = new StructType(NamespaceName.of(), "Y");
+        var nonRecursiveVariantType = new StructType(NamespaceName.of(), "Z");
+        var typesInfo = TypesInfoInMemory.empty();
+        typesInfo.defineSumType(
+            sumType,
+            List.of(
+                new SumVariant(0, recursiveVariantType, recursiveVariantType),
+                new SumVariant(1, nonRecursiveVariantType, nonRecursiveVariantType)
+            ),
+            List.of(),
+            NullSource.INSTANCE
+        );
+        typesInfo.defineStructType(recursiveVariantType, Optional.of(List.of(
+            new Field("x", NativeTypes.box(sumType), NullSource.INSTANCE)
+        )));
+        typesInfo.defineStructType(nonRecursiveVariantType, Optional.of(List.of(
+            new Field("x", NativeTypes.box(NativeTypes.INT_64), NullSource.INSTANCE)
+        )));
+
+        var variant = selectArbitraryVariant(sumType, typesInfo);
+
+        assertThat(variant, equalTo(nonRecursiveVariantType));
+    }
+
+    @Test
+    public void listIsAlwaysNonRecursivelyConstructible() {
+        var sumType = new SumType(NamespaceName.of(), "X");
+        var recursiveVariantType = new StructType(NamespaceName.of(), "Y");
+        var nonRecursiveVariantType = new StructType(NamespaceName.of(), "Z");
+        var typesInfo = TypesInfoInMemory.empty();
+        typesInfo.defineSumType(
+            sumType,
+            List.of(
+                new SumVariant(0, recursiveVariantType, recursiveVariantType),
+                new SumVariant(1, nonRecursiveVariantType, nonRecursiveVariantType)
+            ),
+            List.of(),
+            NullSource.INSTANCE
+        );
+        typesInfo.defineStructType(recursiveVariantType, Optional.of(List.of(
+            new Field("x", NativeTypes.list(sumType), NullSource.INSTANCE)
+        )));
+        typesInfo.defineStructType(nonRecursiveVariantType, Optional.of(List.of(
+            new Field("x", NativeTypes.list(NativeTypes.INT_64), NullSource.INSTANCE)
+        )));
+
+        var variant = selectArbitraryVariant(sumType, typesInfo);
+
+        assertThat(variant, equalTo(recursiveVariantType));
+    }
+
+    @Test
+    public void optionIsAlwaysNonRecursivelyConstructible() {
+        var sumType = new SumType(NamespaceName.of(), "X");
+        var recursiveVariantType = new StructType(NamespaceName.of(), "Y");
+        var nonRecursiveVariantType = new StructType(NamespaceName.of(), "Z");
+        var typesInfo = TypesInfoInMemory.empty();
+        typesInfo.defineSumType(
+            sumType,
+            List.of(
+                new SumVariant(0, recursiveVariantType, recursiveVariantType),
+                new SumVariant(1, nonRecursiveVariantType, nonRecursiveVariantType)
+            ),
+            List.of(),
+            NullSource.INSTANCE
+        );
+        typesInfo.defineStructType(recursiveVariantType, Optional.of(List.of(
+            new Field("x", NativeTypes.option(sumType), NullSource.INSTANCE)
+        )));
+        typesInfo.defineStructType(nonRecursiveVariantType, Optional.of(List.of(
+            new Field("x", NativeTypes.option(NativeTypes.INT_64), NullSource.INSTANCE)
+        )));
+
+        var variant = selectArbitraryVariant(sumType, typesInfo);
+
+        assertThat(variant, equalTo(recursiveVariantType));
+    }
+
+    @Test
+    public void sharedIsRecursivelyConstructibleIffInnerTypeIsRecursivelyConstructible() {
+        var sumType = new SumType(NamespaceName.of(), "X");
+        var recursiveVariantType = new StructType(NamespaceName.of(), "Y");
+        var nonRecursiveVariantType = new StructType(NamespaceName.of(), "Z");
+        var typesInfo = TypesInfoInMemory.empty();
+        typesInfo.defineSumType(
+            sumType,
+            List.of(
+                new SumVariant(0, recursiveVariantType, recursiveVariantType),
+                new SumVariant(1, nonRecursiveVariantType, nonRecursiveVariantType)
+            ),
+            List.of(),
+            NullSource.INSTANCE
+        );
+        typesInfo.defineStructType(recursiveVariantType, Optional.of(List.of(
+            new Field("x", NativeTypes.shared(sumType), NullSource.INSTANCE)
+        )));
+        typesInfo.defineStructType(nonRecursiveVariantType, Optional.of(List.of(
+            new Field("x", NativeTypes.shared(NativeTypes.INT_64), NullSource.INSTANCE)
+        )));
+
+        var variant = selectArbitraryVariant(sumType, typesInfo);
+
+        assertThat(variant, equalTo(nonRecursiveVariantType));
+    }
 }