Preserve Gotlin semantics across packages

internal/lang/metadata_test.go

@@ -0,0 +1,64 @@
+package lang
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestImportedGotlinClassesPreserveReferenceSemantics(t *testing.T) {
+	library, err := Parse(`package platform
+class Lifecycle { fun stopping(): Boolean { return false } }
+fun createLifecycle(): Lifecycle { return Lifecycle() }`)
+	if err != nil {
+		t.Fatal(err)
+	}
+	metadata, err := BuildPackageMetadata(library, "example/platform")
+	if err != nil {
+		t.Fatal(err)
+	}
+	consumer, err := Parse(`package service
+import platform "example/platform"
+class Worker(val lifecycle: platform.Lifecycle) {
+    fun stopped(): Boolean { return lifecycle.stopping() }
+}
+fun create(): platform.Lifecycle { return platform.createLifecycle() }`)
+	if err != nil {
+		t.Fatal(err)
+	}
+	semantic, diagnostics := AnalyzeWithMetadata(consumer, []*PackageMetadata{metadata})
+	if len(diagnostics) != 0 {
+		t.Fatalf("diagnostics: %#v", diagnostics)
+	}
+	fieldType := semantic.ClassInfo["Worker"].Fields["lifecycle"].Type
+	if _, ok := fieldType.(ImportedClassType); !ok {
+		t.Fatalf("type = %#v", fieldType)
+	}
+	output, err := GenerateGoWithMetadata(consumer, []*PackageMetadata{metadata})
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, expected := range []string{"lifecycle *platform.Lifecycle", "func create() *platform.Lifecycle", "platform.CreateLifecycle()"} {
+		if !strings.Contains(string(output), expected) {
+			t.Fatalf("missing %q:\n%s", expected, output)
+		}
+	}
+}
+
+func TestImportedGotlinClassRejectsExplicitPointer(t *testing.T) {
+	library, err := Parse(`package platform class Lifecycle`)
+	if err != nil {
+		t.Fatal(err)
+	}
+	metadata, err := BuildPackageMetadata(library, "example/platform")
+	if err != nil {
+		t.Fatal(err)
+	}
+	consumer, err := Parse(`package service import platform "example/platform" fun use(value: *platform.Lifecycle) {}`)
+	if err != nil {
+		t.Fatal(err)
+	}
+	_, diagnostics := AnalyzeWithMetadata(consumer, []*PackageMetadata{metadata})
+	if len(diagnostics) == 0 || !strings.Contains(diagnostics[0].Message, "already reference-valued") {
+		t.Fatalf("diagnostics: %#v", diagnostics)
+	}
+}