flow like the river

BACK_BACK/node_modules/mongoose/lib/plugins/removeSubdocs.js

@@ -0,0 +1,35 @@
+'use strict';
+
+const each = require('../helpers/each');
+
+/*!
+ * ignore
+ */
+
+module.exports = function removeSubdocs(schema) {
+  const unshift = true;
+  schema.s.hooks.pre('deleteOne', { document: true, query: false }, function removeSubDocsPreRemove(next) {
+    if (this.$isSubdocument) {
+      next();
+      return;
+    }
+    if (this.$__ == null) {
+      next();
+      return;
+    }
+
+    const _this = this;
+    const subdocs = this.$getAllSubdocs();
+
+    each(subdocs, function(subdoc, cb) {
+      subdoc.$__deleteOne(cb);
+    }, function(error) {
+      if (error) {
+        return _this.$__schema.s.hooks.execPost('deleteOne:error', _this, [_this], { error: error }, function(error) {
+          next(error);
+        });
+      }
+      next();
+    });
+  }, null, unshift);
+};