immutable-js · abacaphiliac · Oct 16, 2017 · Oct 17, 2017 · Oct 17, 2017 · Oct 17, 2017
diff --git a/__tests__/Map.ts b/__tests__/Map.ts
@@ -473,4 +473,80 @@ describe('Map', () => {
       Map([[a, Map([[b, Map([[c, 10], [d, 2], [e, 20], [f, 30], [g, 40]])]])]])
     );
   });
+
+  it('supports Symbol keys from object literal', () => {
+    const a = Symbol('A');
+    const b = Symbol('B');
+    const c = Symbol('C');
+    const m = Map.fromOwnEntries({ [a]: 'A', [b]: 'B', [c]: 'C' });
+    expect(m.size).toBe(3);
+    expect(m.get(a)).toBe('A');
+    expect(m.get(b)).toBe('B');
+    expect(m.get(c)).toBe('C');
+  });
+
+  it('Symbol keys from object literal are unique', () => {
+    const a = Symbol('FooBar');
+    const b = Symbol('FooBar');
+    const m = Map.fromOwnEntries({ [a]: 'FizBuz', [b]: 'FooBar' });
+    expect(m.size).toBe(2);
+    expect(m.get(a)).toBe('FizBuz');
+    expect(m.get(b)).toBe('FooBar');
+  });
+
+  it('creates nested Map from object with nested Symbol keys', () => {
+    const a = Symbol('a');
+    const b = Symbol('b');
+    const c = Symbol('c');
+    const e = Symbol('e');
+    const f = Symbol('f');
+    const g = Symbol('g');
+    const map = Map.fromOwnEntries({
+      [a]: { [b]: { [c]: 10, [e]: 20 }, [f]: 30 },
+      [g]: 40,
+    });
+
+    expect(
+      map
+        .get(a)
+        .get(b)
+        .get(c)
+    ).toEqual(10);
+    expect(
+      map
+        .get(a)
+        .get(b)
+        .get(e)
+    ).toEqual(20);
+    expect(map.get(a).get(f)).toEqual(30);
+    expect(map.get(g)).toEqual(40);
+  });
+
+  it('mergeDeep Map from object literal', () => {
+    const a = Symbol('a');
+    const b = Symbol('b');
+    const c = Symbol('c');
+    const d = Symbol('d');
+    const e = Symbol('e');
+    const f = Symbol('f');
+    const g = Symbol('g');
+    const m1 = Map.fromOwnEntries({ [a]: { [b]: { [c]: 1, [d]: 2 } } });
+    const m2 = Map.fromOwnEntries({
+      [a]: { [b]: { [c]: 10, [e]: 20 }, [f]: 30 },
+      [g]: 40,
+    });
+    const expected = Map.fromOwnEntries({
+      [a]: { [b]: { [c]: 10, [d]: 2, [e]: 20 }, [f]: 30 },
+      [g]: 40,
+    });
+    const actual = m1.mergeDeep(m2);
+    expect(actual).toEqual(expected);
+
+    const actualJs = actual.toJS();
+    expect(actualJs[a][b][c]).toEqual(10);
+    expect(actualJs[a][b][d]).toEqual(2);
+    expect(actualJs[a][b][e]).toEqual(20);
+    expect(actualJs[a][f]).toEqual(30);
+    expect(actualJs[g]).toEqual(40);
+  });
 });
diff --git a/src/Map.js b/src/Map.js
@@ -66,6 +66,17 @@ export class Map extends KeyedCollection {
     });
   }
 
+  static fromOwnEntries(source) {
+    return Map(
+      Reflect.ownKeys(source).map(key => [
+        key,
+        typeof source[key] === 'object'
+          ? Map.fromOwnEntries(source[key])
+          : source[key],
+      ])
+    );
+  }
+
   toString() {
     return this.__toString('Map {', '}');
   }

diff --git a/type-definitions/Immutable.d.ts b/type-definitions/Immutable.d.ts
@@ -717,6 +717,48 @@ declare module Immutable {
      * @deprecated Use Map([ [ 'k', 'v' ] ]) or Map({ k: 'v' })
      */
     function of(...keyValues: Array<any>): Map<any, any>;
+
+    /**
+     * Creates a new Map from an object.
+     *
+     * <!-- runkit:activate -->
+     * ```js
+     * const { Map } = require('immutable')
+     * Map.fromOwnEntries({
+     *   foo: 'bar',
+     *   fiz: 'buz'
+     * })
+     * // Map { "foo": "bar", "fiz": "buz" }
+     * ```
+     *
+     * Nested objects are recursively converted into instances of Map.
+     *
+     * <!-- runkit:activate -->
+     * ```js
+     * const { Map } = require('immutable')
+     * Map.fromOwnEntries({
+     *   foo: 'bar',
+     *   fiz: {
+     *     buz: 'qux'
+     *   }
+     * })
+     * // Map { "foo": "bar", "fiz": Map { "buz": "qux" } }
+     * ```
+     *
+     * Symbol keys are supported.
+     *
+     * <!-- runkit:activate -->
+     * ```js
+     * const { Map } = require('immutable')
+     * const fiz = Symbol('fiz');
+     * Map.fromOwnEntries({
+     *   foo: 'bar',
+     *   [fiz]: 'buz'
+     * })
+     * // Map { "foo": "bar", "Symbol(fiz)": "buz" }
+     * ```
+     */
+    function fromOwnEntries(obj: any): Map<any, any>;
   }
 
   /**

diff --git a/type-definitions/immutable.js.flow b/type-definitions/immutable.js.flow
@@ -868,6 +868,7 @@ declare class Map<K, +V> extends KeyedCollection<K, V> mixins UpdatableInCollect
 
   size: number;
 
+  fromOwnEntries(obj: mixed): Map<K, V>;
   set<K_, V_>(key: K_, value: V_): Map<K | K_, V | V_>;
   delete(key: K): this;
   remove(key: K): this;