Assign tags to structs

1 files changed, 23 insertions, 0 deletions

diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenDefineStructTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenDefineStructTests.java
index 6464dfe0..932f626a 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenDefineStructTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenDefineStructTests.java
@@ -16,6 +16,8 @@ import java.util.List;
 import java.util.Map;
 
 import static org.shedlang.compiler.patio.PatioTesting.serialize;
+import static org.zwobble.precisely.AssertThat.assertThat;
+import static org.zwobble.precisely.Matchers.equalTo;
 
 @ExtendWith({SnapshotResolver.class})
 public class PatioCodeGenDefineStructTests {
@@ -40,4 +42,25 @@ public class PatioCodeGenDefineStructTests {
 
         snapshotter.assertSnapshot(serialize(result));
     }
+
+    @Test
+    public void structsAreAssignedSequentialTags(Snapshotter snapshotter) throws IOException {
+        // TODO: we can probably optimise this to ensure that (for instance)
+        // variants of the same sum type have sequential tags, but source order
+        // will suffice for now
+        var structType1 = Types.struct(NamespaceName.of("Example", "Project"), "User");
+        var structType2 = Types.struct(NamespaceName.of("Example", "Project"), "Id");
+        var instruction1 = Instructions.defineStruct(structType1, List.of());
+        var instruction2 = Instructions.defineStruct(structType1, List.of());
+        var typeInfos = TypeInfos.EMPTY
+            .addStructTypeInfo(structType1, StructTypeInfo.fromFields(P.orderedMap()))
+            .addStructTypeInfo(structType2, StructTypeInfo.fromFields(P.orderedMap()));
+        var context = PatioCodeGenContext.forTypeInfos(typeInfos);
+
+        context = PatioCodeGen.generateInstruction(instruction1, context);
+        context = PatioCodeGen.generateInstruction(instruction2, context);
+
+        assertThat(context.tag(structType1), equalTo(0));
+        assertThat(context.tag(structType2), equalTo(1));
+    }
 }