[es6] Implement inner scope for functions with destructuring

[es6] Implement inner scope for functions with destructuring

R=adamk@chromium.org, littledan@chromium.org
BUG=v8:811
LOG=N

Committed: https://crrev.com/207fbbbe327b782c65ba4f1d0f626d81629758c7
Cr-Commit-Position: refs/heads/master@{#29674}

[caitp (gmail), 2015-07-13 16:00:51]

caitpotter88@gmail.com changed reviewers:
+ caitpotter88@gmail.com

[caitp (gmail), 2015-07-13 16:00:52]

https://codereview.chromium.org/1240463002/diff/1/src/scopes.cc
File src/scopes.cc (right):

https://codereview.chromium.org/1240463002/diff/1/src/scopes.cc#newcode1369
src/scopes.cc:1369: outer_scope()->DeclarationScope()->AllocateStackSlot(var);
Won't DeclarationScope() get outer_scope() on its own if is_block_scope() is
true? It looks like it does

[adamk, 2015-07-13 19:27:31]

https://codereview.chromium.org/1240463002/diff/1/test/mjsunit/harmony/destru...
File test/mjsunit/harmony/destructuring.js (right):

https://codereview.chromium.org/1240463002/diff/1/test/mjsunit/harmony/destru...
test/mjsunit/harmony/destructuring.js:761: // TODO(rossberg): Check for variable
collision.
Do you mean to take care of this in this patch or a followup?

[rossberg, 2015-07-14 06:24:51]

https://codereview.chromium.org/1240463002/diff/1/src/scopes.cc
File src/scopes.cc (right):

https://codereview.chromium.org/1240463002/diff/1/src/scopes.cc#newcode1369
src/scopes.cc:1369: outer_scope()->DeclarationScope()->AllocateStackSlot(var);
On 2015/07/13 16:00:51, caitp wrote:
> Won't DeclarationScope() get outer_scope() on its own if is_block_scope() is
> true? It looks like it does

Not if it is a block scope that is a declaration scope, which is exactly what
this CL introduces. Without this, you'd run into an infinite loop.

https://codereview.chromium.org/1240463002/diff/1/test/mjsunit/harmony/destru...
File test/mjsunit/harmony/destructuring.js (right):

https://codereview.chromium.org/1240463002/diff/1/test/mjsunit/harmony/destru...
test/mjsunit/harmony/destructuring.js:761: // TODO(rossberg): Check for variable
collision.
On 2015/07/13 19:27:31, adamk wrote:
> Do you mean to take care of this in this patch or a followup?

I leave that for a future CL. Leaving out this check for now does not break
anything, other than allowing a few more programs.

[adamk, 2015-07-14 18:33:31]

lgtm

[rossberg, 2015-07-15 10:30:31]

The CQ bit was checked by rossberg@chromium.org

[commit-bot: I haz the power, 2015-07-15 10:30:36]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1240463002/20001

[commit-bot: I haz the power, 2015-07-15 10:59:57]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-07-15 11:00:07]

Patchset 2 (id:??) landed as
https://crrev.com/207fbbbe327b782c65ba4f1d0f626d81629758c7
Cr-Commit-Position: refs/heads/master@{#29674}