chushihua

node_modules/postcss-modules-extract-imports/lib/topologicalSort.js

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+"use strict";
+
+var PERMANENT_MARKER = 2;
+var TEMPORARY_MARKER = 1;
+
+function createError(node, graph) {
+  var er = new Error("Nondeterministic import's order");
+
+  var related = graph[node];
+  var relatedNode = related.find(function (relatedNode) {
+    return graph[relatedNode].indexOf(node) > -1;
+  });
+
+  er.nodes = [node, relatedNode];
+
+  return er;
+}
+
+function walkGraph(node, graph, state, result, strict) {
+  if (state[node] === PERMANENT_MARKER) return;
+  if (state[node] === TEMPORARY_MARKER) {
+    if (strict) return createError(node, graph);
+    return;
+  }
+
+  state[node] = TEMPORARY_MARKER;
+
+  var children = graph[node];
+  var length = children.length;
+
+  for (var i = 0; i < length; ++i) {
+    var er = walkGraph(children[i], graph, state, result, strict);
+    if (er instanceof Error) return er;
+  }
+
+  state[node] = PERMANENT_MARKER;
+
+  result.push(node);
+}
+
+function topologicalSort(graph, strict) {
+  var result = [];
+  var state = {};
+
+  var nodes = Object.keys(graph);
+  var length = nodes.length;
+
+  for (var i = 0; i < length; ++i) {
+    var er = walkGraph(nodes[i], graph, state, result, strict);
+    if (er instanceof Error) return er;
+  }
+
+  return result;
+}
+
+module.exports = topologicalSort;