some progress

node_modules/mongoose/lib/schema/map.js

@@ -0,0 +1,84 @@
+'use strict';
+
+/*!
+ * ignore
+ */
+
+const MongooseMap = require('../types/map');
+const SchemaMapOptions = require('../options/SchemaMapOptions');
+const SchemaType = require('../schematype');
+/*!
+ * ignore
+ */
+
+class Map extends SchemaType {
+  constructor(key, options) {
+    super(key, options, 'Map');
+    this.$isSchemaMap = true;
+  }
+
+  set(option, value) {
+    return SchemaType.set(option, value);
+  }
+
+  cast(val, doc, init) {
+    if (val instanceof MongooseMap) {
+      return val;
+    }
+
+    const path = this.path;
+
+    if (init) {
+      const map = new MongooseMap({}, path, doc, this.$__schemaType);
+
+      if (val instanceof global.Map) {
+        for (const key of val.keys()) {
+          let _val = val.get(key);
+          if (_val == null) {
+            _val = map.$__schemaType._castNullish(_val);
+          } else {
+            _val = map.$__schemaType.cast(_val, doc, true, null, { path: path + '.' + key });
+          }
+          map.$init(key, _val);
+        }
+      } else {
+        for (const key of Object.keys(val)) {
+          let _val = val[key];
+          if (_val == null) {
+            _val = map.$__schemaType._castNullish(_val);
+          } else {
+            _val = map.$__schemaType.cast(_val, doc, true, null, { path: path + '.' + key });
+          }
+          map.$init(key, _val);
+        }
+      }
+
+      return map;
+    }
+
+    return new MongooseMap(val, path, doc, this.$__schemaType);
+  }
+
+  clone() {
+    const schematype = super.clone();
+
+    if (this.$__schemaType != null) {
+      schematype.$__schemaType = this.$__schemaType.clone();
+    }
+    return schematype;
+  }
+}
+
+/**
+ * This schema type's name, to defend against minifiers that mangle
+ * function names.
+ *
+ * @api public
+ */
+Map.schemaName = 'Map';
+
+Map.prototype.OptionsConstructor = SchemaMapOptions;
+
+Map.defaultOptions = {};
+
+module.exports = Map;