code review 224068: go/scanner: the position of '\n's chars must be the las...

go/scanner: the position of '\n's chars must be the last position of the current line

Background: This didn't matter until recently, because '\n' don't appear as token starts
in source code and thus the exact position was irrelevant (and set as was easiest in the
code). With auto semicolon insertion, a virtual semicolon may be inserted when a '\n' is
seen. The position of the semicolon is the position of the '\n'. Without this fix, these
semicolons appeared on the next line instead of the line where they were inserted.  This
affected the association of comments to declarations in the parser. As a result, some
lead comments where considered line comments, not collected in the ast, and not shown in
godoc pages. (This affected only godoc pages, not gofmt-formatted programs).

Fixes issue 592.

[gri, 2010-02-26 02:49:47]

Hello rsc (cc: golang-dev@googlegroups.com),

I'd like you to review this change.

[rsc, 2010-02-26 02:51:36]

LGTM

[gri, 2010-02-26 19:23:26]

*** Submitted as http://code.google.com/p/go/source/detail?r=b53a867d0db6 ***

go/scanner: the position of '\n's chars must be the last position of the current
line

Background: This didn't matter until recently, because '\n' don't appear as
token starts
in source code and thus the exact position was irrelevant (and set as was
easiest in the
code). With auto semicolon insertion, a virtual semicolon may be inserted when a
'\n' is
seen. The position of the semicolon is the position of the '\n'. Without this
fix, these
semicolons appeared on the next line instead of the line where they were
inserted.  This
affected the association of comments to declarations in the parser. As a result,
some
lead comments where considered line comments, not collected in the ast, and not
shown in
godoc pages. (This affected only godoc pages, not gofmt-formatted programs).

Fixes issue 592.

R=rsc
CC=golang-dev
http://codereview.appspot.com/224068