algorithm improvements

Author: sokra

lib/util/findGraphRoots.js

@@ -113,9 +113,6 @@ module.exports = (items, getDependencies) => {
 								cycle = new Cycle();
 								cycle.nodes.add(dependency);
 								dependency.cycle = cycle;
-								// Assume this is a root cycle
-								// It will removed if not on node leaving
-								rootCycles.add(cycle);
 							}
 							// set cycle property for each node in the cycle
 							// if nodes are already part of a cycle
@@ -129,7 +126,6 @@ module.exports = (items, getDependencies) => {
 								if (node.cycle) {
 									if (node.cycle !== cycle) {
 										// merge cycles
-										rootCycles.delete(node.cycle);
 										for (const cycleNode of node.cycle.nodes) {
 											cycleNode.cycle = cycle;
 											cycle.nodes.add(cycleNode);
@@ -153,7 +149,8 @@ module.exports = (items, getDependencies) => {
 							roots.delete(dependency);
 							break;
 						case DONE_MAYBE_ROOT_CYCLE_MARKER:
-							// This node has be visited yet and is currently part of a completed root cycle
+							// This node has be visited yet and
+							// is maybe currently part of a completed root cycle
 							// we found a new reference to the cycle
 							// so it's not really a root cycle
 							// remove the cycle from the root cycles
@@ -167,28 +164,16 @@ module.exports = (items, getDependencies) => {
 					// All dependencies of the current node has been visited
 					// we leave the node
 					stack.pop();
-					const node = topOfStack.node;
-					// If the leaving node is part of a cycle
-					// and parent node is not part of the same cycle
-					// we have a parent-child-relationship between these cycles
-					// and remove the child cycle from the rootCycles
-					const cycle = node.cycle;
-					if (cycle) {
-						if (stack.length > 0) {
-							const parent = stack[stack.length - 1];
-							if (parent.node.cycle !== cycle) {
-								rootCycles.delete(cycle);
-								node.marker = DONE_MARKER;
-								continue;
-							}
-						}
-						node.marker = DONE_MAYBE_ROOT_CYCLE_MARKER;
-					} else {
-						node.marker = DONE_MARKER;
-					}
+					topOfStack.node.marker = DONE_MARKER;
 				}
 			}
-			if (selectedNode.marker === DONE_MARKER) {
+			const cycle = selectedNode.cycle;
+			if (cycle) {
+				for (const node of cycle.nodes) {
+					node.marker = DONE_MAYBE_ROOT_CYCLE_MARKER;
+				}
+				rootCycles.add(cycle);
+			} else {
 				selectedNode.marker = DONE_AND_ROOT_MARKER;
 				roots.add(selectedNode);
 			}