fix(UrlSearchParams): change a behavior when a param value is null or undefined (#11990)

modules/@angular/http/src/url_search_params.ts

@@ -102,6 +102,10 @@ export class URLSearchParams {
   getAll(param: string): string[] { return this.paramsMap.get(param) || []; }
 
   set(param: string, val: string) {
+    if (val === void 0 || val === null) {
+      this.delete(param);
+      return;
+    }
     const list = this.paramsMap.get(param) || [];
     list.length = 0;
     list.push(val);
@@ -124,6 +128,7 @@ export class URLSearchParams {
   }
 
   append(param: string, val: string): void {
+    if (val === void 0 || val === null) return;
     const list = this.paramsMap.get(param) || [];
     list.push(val);
     this.paramsMap.set(param, list);

modules/@angular/http/test/url_search_params_spec.ts

@@ -149,5 +149,23 @@ export function main() {
       expect(paramsC.toString()).toEqual('a=2&q=4%2B&c=8');
     });
 
+    it('should remove the parameter when set to undefined or null', () => {
+      const params = new URLSearchParams('q=Q');
+      params.set('q', undefined);
+      expect(params.has('q')).toBe(false);
+      expect(params.toString()).toEqual('');
+      params.set('q', null);
+      expect(params.has('q')).toBe(false);
+      expect(params.toString()).toEqual('');
+    });
+
+    it('should ignore the value when append undefined or null', () => {
+      const params = new URLSearchParams('q=Q');
+      params.append('q', undefined);
+      expect(params.toString()).toEqual('q=Q');
+      params.append('q', null);
+      expect(params.toString()).toEqual('q=Q');
+    });
+
   });
 }