chore: import upstream snapshot with attribution

tools/challenge-parser/parser/plugins/utils/find-all.js

@@ -0,0 +1,27 @@
+const visit = require('unist-util-visit');
+const _ = require('lodash');
+
+/**
+ * Finds all nodes in a tree that match a given condition. This is a trivial
+ * extension of `unist-util-find` that returns all matching nodes.
+ *
+ * @param {Object} tree - The unist tree to search through.
+ * @param {Function|Object} condition - The condition to match nodes
+ * against. This can be a function that accepts a single node argument or an object to match.
+ * @returns {Array} An array of nodes that match the condition.
+ */
+function findAll(tree, condition) {
+  const predicate = _.iteratee(condition);
+  const results = [];
+  visit(tree, node => {
+    if (predicate(node)) {
+      results.push(node);
+    }
+
+    return visit.CONTINUE;
+  });
+
+  return results;
+}
+
+module.exports.findAll = findAll;