Merge pull request immutable-js#727 from glenjamin/map-factory

leebyron · leebyron · commit d94141223d56 · 2016-01-05T19:31:53.000-08:00
Short-hand constructor for Map, taking flat arguments
diff --git a/__tests__/Map.ts b/__tests__/Map.ts
@@ -88,6 +88,20 @@ describe('Map', () => {
     expect(m.toJS()).toEqual({ 'length': 3, '1': 'one' });
   });
 
+  it('accepts flattened pairs via of()', () => {
+    var m: Map<any, any> = Map.of(1, 'a', 2, 'b', 3, 'c');
+    expect(m.size).toBe(3);
+    expect(m.get(1)).toBe('a');
+    expect(m.get(2)).toBe('b');
+    expect(m.get(3)).toBe('c');
+  });
+
+  it('does not accept mismatched flattened pairs via of()', () => {
+    expect(() => {
+      Map.of(1, 2, 3);
+    }).toThrow('Missing value for key: 3');
+  });
+
   it('converts back to JS object', () => {
     var m = Map({'a': 'A', 'b': 'B', 'c': 'C'});
     expect(m.toObject()).toEqual({'a': 'A', 'b': 'B', 'c': 'C'});
diff --git a/dist/immutable.d.ts b/dist/immutable.d.ts
@@ -420,6 +420,11 @@ declare module Immutable {
      * True if the provided value is a Map
      */
     function isMap(maybeMap: any): boolean;
+
+    /**
+     * Creates a new Map from alternating keys and values
+     */
+    function of(...keyValues: any[]): Map<any, any>;
   }
 
   /**
diff --git a/dist/immutable.js b/dist/immutable.js
@@ -1222,6 +1222,17 @@
         });
     }
 
+    Map.of = function() {var keyValues = SLICE$0.call(arguments, 0);
+      return emptyMap().withMutations(function(map ) {
+        for (var i = 0; i < keyValues.length; i += 2) {
+          if (i + 1 >= keyValues.length) {
+            throw new Error('Missing value for key: ' + keyValues[i]);
+          }
+          map.set(keyValues[i], keyValues[i + 1]);
+        }
+      });
+    };
+
     Map.prototype.toString = function() {
       return this.__toString('Map {', '}');
     };
diff --git a/dist/immutable.min.js b/dist/immutable.min.js
diff --git a/src/Map.js b/src/Map.js
@@ -37,6 +37,17 @@ export class Map extends KeyedCollection {
       });
   }
 
+  static of(...keyValues) {
+    return emptyMap().withMutations(map => {
+      for (var i = 0; i < keyValues.length; i += 2) {
+        if (i + 1 >= keyValues.length) {
+          throw new Error('Missing value for key: ' + keyValues[i]);
+        }
+        map.set(keyValues[i], keyValues[i + 1]);
+      }
+    });
+  }
+
   toString() {
     return this.__toString('Map {', '}');
   }
diff --git a/type-definitions/Immutable.d.ts b/type-definitions/Immutable.d.ts
@@ -420,6 +420,11 @@ declare module Immutable {
      * True if the provided value is a Map
      */
     function isMap(maybeMap: any): boolean;
+
+    /**
+     * Creates a new Map from alternating keys and values
+     */
+    function of(...keyValues: any[]): Map<any, any>;
   }
 
   /**
