object destructuring assignment with rename throws error

[effervescentia]

TypeScript Version: 2.0.2 (and 2.1.0-dev.20160830)

Code

// A *self-contained* demonstration of the problem follows...

let _value: SomeType;
let _other: OtherType;

({ value: _value, other: _other } = someFunction());

Expected behavior:
_value should be set to the value value returned in the result of someFunction()
same with _other

(this works in 2.0.0 and 2.0.0-dev.20160628)

Actual behavior:
Throws errors:
error: cannot find name 'value'
error: cannot find name 'other'

[mhegazy]

looks like there is something else going on here..

c:\test\93>tsc --v
Version 2.1.0-dev.20160901

c:\test\93>type C:\test\93\src\index.ts
// A *self-contained* demonstration of the problem follows...

declare function someFunction(): { value: number, other: number };

let _value: number;
let _other: number;

({ value: _value, other: _other } = someFunction());
c:\test\93>tsc C:\test\93\src\index.ts

c:\test\93>echo %ERRORLEVEL%
0

[effervescentia]

Exact location of the failing code
https://github.com/groupby/searchandiser-ui/blob/master/test/unit/tags/_suite.ts#L18

The error generated when running with 2.0.2:

I'll try to put together a failing case that doesn't rely on my codebase 😜

[thorn0]

I've reproduced this:

d:\dev\zzzqwd>tsc -v
Version 2.0.7

d:\dev\zzzqwd>type index.ts

function qux(bar: string) {
  const obj = { value: 1 };
  let foo: number;
  ({ value: foo } = obj);
  let log = () => bar;
}

d:\dev\zzzqwd>tsc index.ts
index.ts(5,6): error TS2304: Cannot find name 'value'.

playground

[effervescentia]

Yes! Thank you, I knew I wasn't crazy

[kpreisser]

Hi @mhegazy,
now that a repro is available, should this issue be marked as bug? I can still reproduce the error with the current master branch.
Thanks!

[sandersn]

Fix is up at #13708