Bug: expireAfterSeconds 0 can't be passed to Index decorator

[enten]

Issue type:

[ ] question
[x] bug report
[ ] feature request
[ ] documentation issue

Database system/driver:

[ ] cordova
[x] mongodb
[ ] mssql
[ ] mysql / mariadb
[ ] oracle
[ ] postgres
[ ] cockroachdb
[ ] sqlite
[ ] sqljs
[ ] react-native
[ ] expo

TypeORM version:

[x] latest
[ ] @next
[ ] 0.x.x (or put your version here)

Steps to reproduce or a small repository showing the problem:

Currently, expireAfterSeconds: 0 can't be passed to Index decorator:

import { Column, Entity, Index, getMetadataArgsStorage } from 'typeorm';

@Entity()
export class Foo {
  @Column('date')
  @Index({ expireAfterSeconds: 0 })
  expireAt: Date;
}

console.log(getMetadataArgsStorage().indices);
/*
[ { target: [Function: Foo],
  name: undefined,
  columns: [ 'expireAt' ],
  synchronize: true,
  where: undefined,
  unique: false,
  spatial: false,
  fulltext: false,
  sparse: false,
  background: false,
  expireAfterSeconds: undefined } ]
*/

We can fix that with one line change:

diff --git a/src/decorator/Index.ts b/src/decorator/Index.ts
index 7b6197b..45683a5 100644
--- a/src/decorator/Index.ts
+++ b/src/decorator/Index.ts
@@ -79,7 +79,7 @@ export function Index(nameOrFieldsOrOptions?: string|string[]|((object: any) =>
             fulltext: options && options.fulltext ? true : false,
             sparse: options && options.sparse ? true : false,
             background: options && options.background ? true : false,
-            expireAfterSeconds: options && options.expireAfterSeconds ? options.expireAfterSeconds : undefined
+            expireAfterSeconds: options ? options.expireAfterSeconds : undefined
         } as IndexMetadataArgs);
     };
 }

I will make a PR.