|author||Scott Graham <email@example.com>||Tue Jan 21 12:14:43 2020 -0800|
|committer||Commit Bot <firstname.lastname@example.org>||Wed Jan 22 22:15:03 2020 +0000|
format: Fix not getting to fixed point in one step In https://gn-review.googlesource.com/c/gn/+/7140/ some styles of suffix comments the formatter would wrap the suffix comments. But on reapplying the formatter a second time, the parse tree is slightly different. The second time through, the wrapped comment is the only thing on a line separating two statements. a = 1 b + c # x 2 # y 3 d = e 4 The ParseNode doesn't have a LocationRange that includes the suffix comments, so when the formatter attempts to determine if there was a blank line between two statements, it incorrectly decides there should be an additional blank line added (because the end of the first statement is not directly next to the start of the next one). That is, the "end" of the "a=b+c" is line 2, not line 3. I fiddled around with trying to amend the parse tree to make the comments be included in the range of the node, but I didn't come up with a reasonable way to do that. Instead, have the formatter calculate the "real" range at formatting time, so instead of simply using line numbers for A and B to determine if they're split, it walks down A looking for suffix comments and finds the lowest down one and uses that instead. In the example above, the walk will determine that "a=b+c" really ends on line 3, so is adjacent to "d=e" on line 4 and no blank line should be inserted. This makes the recent Chromium test reformat https://chromium-review.googlesource.com/c/chromium/src/+/2011169/ "stick" in that no further changes are made if the formatter is run on it again. Bug: gn:141 Change-Id: If320a87feec9671d2368a799e9e396866698561d Reviewed-on: https://gn-review.googlesource.com/c/gn/+/7180 Commit-Queue: Scott Graham <email@example.com> Reviewed-by: Brett Wilson <firstname.lastname@example.org> Reviewed-by: Nico Weber <email@example.com>
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