gn format: fix comments at end of blocks

gn format: fix comments at end of blocks

Fixes comments at the end of a block like:

  stuff() {
    sources = []
    # wee
  }

This is done by storing an EndNode (instead of just a Token) as the
end of Block and List nodes. This means there's a node in the tree
traversal for the trailing ], and gives a place to attach the comment.

Also collapses some of the expression output code to reuse Sequence.

R=brettw@chromium.org
BUG=348474
Committed: https://crrev.com/f7e13e52cddeda696e71c0ab4c08876ddeef4330
Cr-Commit-Position: refs/heads/master@{#297226}

[scottmg, 2014-09-26 18:39:10]

scottmg@chromium.org changed reviewers:
+ brettw@chromium.org

[brettw, 2014-09-26 21:37:34]

https://codereview.chromium.org/607173002/diff/60001/tools/gn/parse_tree.h
File tools/gn/parse_tree.h (right):

https://codereview.chromium.org/607173002/diff/60001/tools/gn/parse_tree.h#ne...
tools/gn/parse_tree.h:28: class EndNode;
Can you sort this list?

https://codereview.chromium.org/607173002/diff/60001/tools/gn/parse_tree.h#ne...
tools/gn/parse_tree.h:480: class EndNode : public IdentifierNode {
Can you document here what this is for? It's not self-explanatory.

It's weird it inherits from identifier since this isn't an identifier. I guess
you just want a node with a token, but I think it would be more clear to
duplicate this, and also provide a more reasonable implementation of Execute
(just return Value() I guess).

[scottmg, 2014-09-26 21:47:33]

Thanks

https://codereview.chromium.org/607173002/diff/60001/tools/gn/parse_tree.h
File tools/gn/parse_tree.h (right):

https://codereview.chromium.org/607173002/diff/60001/tools/gn/parse_tree.h#ne...
tools/gn/parse_tree.h:28: class EndNode;
On 2014/09/26 21:37:34, brettw wrote:
> Can you sort this list?

Done.

https://codereview.chromium.org/607173002/diff/60001/tools/gn/parse_tree.h#ne...
tools/gn/parse_tree.h:480: class EndNode : public IdentifierNode {
On 2014/09/26 21:37:34, brettw wrote:
> Can you document here what this is for? It's not self-explanatory.

Done.

> It's weird it inherits from identifier since this isn't an identifier. I guess
> you just want a node with a token, but I think it would be more clear to
> duplicate this, and also provide a more reasonable implementation of Execute
> (just return Value() I guess).

Yes, that was just unnecessary expedience, made it a plain ParseNode with its
own implementation.

[brettw, 2014-09-29 17:09:14]

lgtm

[scottmg, 2014-09-29 18:18:20]

The CQ bit was checked by scottmg@chromium.org

[commit-bot: I haz the power, 2014-09-29 18:20:08]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/607173002/80001

[commit-bot: I haz the power, 2014-09-29 19:21:21]

Committed patchset #5 (id:80001) as 5a45b8be01f2b47842323466d34f5e34418eb895

[commit-bot: I haz the power, 2014-09-29 19:22:16]

Patchset 5 (id:??) landed as
https://crrev.com/f7e13e52cddeda696e71c0ab4c08876ddeef4330
Cr-Commit-Position: refs/heads/master@{#297226}