cmd/gofmt: Comments are incorrectly moved across commas

[varungandhi-src]

Go version

HEAD

Output of go env in your module/workspace:

n/a - Tested on https://go.dev/play/

What did you do?

Write some code like:

foo(x, /* name */ y)

Then run go fmt

What did you see happen?

The code gets re-formatted to:

foo(x /* name */, y)

CleanShot.2024-06-26.at.18.12.00.mp4

This changes the meaning of the comment, as it seems to apply to the preceding argument.

This problem also applies to commas in slice literals and comments. I have not checked the behavior with other grammar constructs that have commas.

What did you expect to see?

The comment should respect the position relative to the comma. Otherwise, one has to introduce an unnecessary line break to force the comment from not being moved to the wrong place.

[gabyhelp]

Similar Issues

• cmd/gofmt: Faulty Comment Re-Arrangement in Argument Lists #13113
• gofmt reorders inline argument comments #19341
• go/printer: /*-style comments placed after commas in argument lists #3062
• cmd/gofmt: comment in return params is misplaced #28433
• cmd/gofmt: extra indentations when adding comments #32480
• cmd/gofmt: gofmt does not format indented comments #53005
• cmd/gofmt: incorrect indentation of comments for LabeledStmt #27964
• cmd/gofmt: Slice literal condensed to one line and comment moved outside if comment is last line #18599
• cmd/gofmt: call("arg", newline /* comment */) is changed to syntax error #27574
• cmd/gofmt: odd comment alignment #9064

_{(Emoji vote if this was helpful or unhelpful; more detailed feedback welcome in this discussion.)}

[varungandhi-src]

Closing as duplicate of #13113