diff --git a/publicodes/source/cyclesLib/graph.ts b/publicodes/source/cyclesLib/graph.ts
index 625dc640f..c94a6eba0 100644
--- a/publicodes/source/cyclesLib/graph.ts
+++ b/publicodes/source/cyclesLib/graph.ts
@@ -60,7 +60,8 @@ export function flattenOneLevelRemplaceLoops(naiveGraph: Graph) {
 	const ROLLNodesTypes = new Proxy(
 		{},
 		{
-			get: (target, name) => (name in target ? target[name] : new Set())
+			get: (target, name) =>
+				name in target ? target[name] : (target[name] = new Set())
 		}
 	)
 	ROLLEdges.forEach(e => {
diff --git a/publicodes/test/cycles.test.js b/publicodes/test/cycles.test.js
index 70aba30d9..46796d8ac 100644
--- a/publicodes/test/cycles.test.js
+++ b/publicodes/test/cycles.test.js
@@ -6,15 +6,72 @@ import { flattenOneLevelRemplaceLoops } from '../source/cyclesLib/graph'
 
 import { cyclicDependencies } from '../source/cyclesLib'
 
-describe('Remplace loops flatten-o-tron 2500 ™', () => {
-	it(`should replace 2 nodes referencing each other with formule and replacedBy by
-	4 nodes without loop`, () => {
+describe('ROLL flatten-o-tron 2500 ™', () => {
+	it('should replace 2 ROLL nodes with	4 nodes without loop', () => {
 		const g = new graphlib.Graph()
 
 		g.setEdge('b', 'c', { type: DependencyType.formule })
 		g.setEdge('c', 'b', { type: DependencyType.replacedBy })
 
 		const flattenedGraph = flattenOneLevelRemplaceLoops(g)
+
+		expect(flattenedGraph.nodes()).to.deep.equal([
+			'b [depType: 0]',
+			'c [depType: 0]',
+			'c [depType: 1]',
+			'b [depType: 1]'
+		])
+		expect(flattenedGraph.edges()).to.deep.equal([
+			{ v: 'b [depType: 0]', w: 'c [depType: 0]' },
+			{ v: 'c [depType: 1]', w: 'b [depType: 1]' }
+		])
+	})
+
+	it('should replace 2 ROLL nodes in context of a larger graph', () => {
+		const g = new graphlib.Graph()
+
+		g.setEdge('a', 'b', { type: DependencyType.formule })
+		g.setEdge('a', 'c', { type: DependencyType.formule })
+		g.setEdge('b', 'c', { type: DependencyType.formule })
+		g.setEdge('c', 'b', { type: DependencyType.replacedBy })
+		g.setEdge('b', 'd', { type: DependencyType.formule })
+		g.setEdge('c', 'd', { type: DependencyType.formule })
+
+		const flattenedGraph = flattenOneLevelRemplaceLoops(g)
+
+		expect(flattenedGraph.nodes()).to.deep.equal([
+			'a',
+			'b [depType: 1]',
+			'b [depType: 0]',
+			'c [depType: 1]',
+			'c [depType: 0]',
+			'd'
+		])
+		expect(flattenedGraph.edges()).to.have.deep.members([
+			{ v: 'a', w: 'b [depType: 0]' },
+			{ v: 'a', w: 'b [depType: 1]' },
+			{ v: 'a', w: 'c [depType: 0]' },
+			{ v: 'a', w: 'c [depType: 1]' },
+			{ v: 'b [depType: 0]', w: 'c [depType: 0]' },
+			{ v: 'c [depType: 1]', w: 'b [depType: 1]' },
+			{ v: 'b [depType: 0]', w: 'd' },
+			{ v: 'b [depType: 1]', w: 'd' },
+			{ v: 'c [depType: 0]', w: 'd' },
+			{ v: 'c [depType: 1]', w: 'd' }
+		])
+	})
+
+	it('should not replace any nodes in a 2-level formule + remplace loop', () => {
+		const g = new graphlib.Graph()
+
+		g.setEdge('a', 'b', { type: DependencyType.formule })
+		g.setEdge('b', 'c', { type: DependencyType.formule })
+		g.setEdge('c', 'a', { type: DependencyType.replacedBy })
+
+		const flattenedGraph = flattenOneLevelRemplaceLoops(g)
+
+		expect(flattenedGraph.nodes()).to.deep.equal(['a', 'b', 'c'])
+		expect(flattenedGraph.edges()).to.deep.equal(g.edges())
 	})
 })