From af098e56e6d41eb3d4517bfd777530c593d9802f Mon Sep 17 00:00:00 2001
From: hperl <34397+hperl@users.noreply.github.com>
Date: Mon, 4 Jul 2022 15:54:31 +0200
Subject: [PATCH] feat: support nested userset rewrites

---
 internal/check/engine.go | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/internal/check/engine.go b/internal/check/engine.go
index ed3fbabcf..facbfd534 100644
--- a/internal/check/engine.go
+++ b/internal/check/engine.go
@@ -255,6 +255,11 @@ func (e *Engine) checkUsersetRewrite(
 				Tuple: *r,
 				Type:  expand.ComputedUserset,
 			}, e.checkComputedUserset(ctx, r, c, restDepth)))
+		case *ast.UsersetRewrite:
+			checks = append(checks, checkgroup.WithEdge(checkgroup.Edge{
+				Tuple: *r,
+				Type:  toExpandNodeType(c.Operation),
+			}, e.checkUsersetRewrite(ctx, r, c, restDepth)))
 		}
 	}
 
@@ -263,6 +268,19 @@ func (e *Engine) checkUsersetRewrite(
 	}
 }
 
+func toExpandNodeType(op ast.SetOperation) expand.NodeType {
+	switch op {
+	case ast.SetOperationUnion:
+		return expand.Union
+	case ast.SetOperationDifference:
+		return expand.Exclusion
+	case ast.SetOperationIntersection:
+		return expand.Intersection
+	default:
+		return expand.Union
+	}
+}
+
 func (e *Engine) checkComputedUserset(
 	ctx context.Context,
 	r *RelationTuple,