feat: basic PoC of Map type re: #681

lib/schema/index.js

@@ -25,6 +25,8 @@ exports.Mixed = require('./mixed');
 
 exports.Decimal128 = exports.Decimal = require('./decimal128');
 
+exports.Map = require('./map');
+
 // alias
 
 exports.Oid = exports.ObjectId;

lib/schema/map.js

@@ -0,0 +1,25 @@
+/*!
+ * ignore
+ */
+
+const MongooseMap = require('../types/map');
+const SchemaType = require('../schematype');
+
+/*!
+ * ignore
+ */
+
+class SchemaMap extends SchemaType {
+  constructor(key, options) {
+    super(key, options, 'Map');
+  }
+
+  cast(val, doc) {
+    if (val instanceof MongooseMap) {
+      return val;
+    }
+    return new MongooseMap(val, this.path, doc);
+  }
+}
+
+module.exports = SchemaMap;

lib/types/index.js

@@ -13,4 +13,6 @@ exports.DocumentArray = require('./documentarray');
 exports.Decimal128 = require('./decimal128');
 exports.ObjectId = require('./objectid');
 
+exports.Map = require('./map');
+
 exports.Subdocument = require('./subdocument');

lib/types/map.js

@@ -0,0 +1,45 @@
+/*!
+ * ignore
+ */
+
+class MongooseMap extends Map {
+  constructor(v, path, doc) {
+    if (v != null && v.constructor.name === 'Object') {
+      v = Object.keys(v).reduce((arr, key) => arr.concat([[key, v[key]]]), []);
+    }
+    super(v);
+
+    this.$__parent = doc;
+    this.$__path = path;
+  }
+
+  set(key, value) {
+    super.set(key, value);
+
+    if (this.$__parent != null) {
+      this.$__parent.markModified(this.$__path + '.' + key);
+    }
+  }
+
+  toBSON() {
+    return new Map(this);
+  }
+
+  toJSON() {
+    return new Map(this);
+  }
+}
+
+Object.defineProperty(MongooseMap.prototype, '$__parent', {
+  enumerable: false,
+  writable: true,
+  configurable: false
+});
+
+Object.defineProperty(MongooseMap.prototype, '$__path', {
+  enumerable: false,
+  writable: true,
+  configurable: false
+});
+
+module.exports = MongooseMap;