Tall style: Preserve blank line between line comments and subsequent code?

[munificent]

The new in-progress style removes all blank lines between a comment and subsequent code when it occurs in a block or at the top level. For example, given:

// Comment.

main() {}

It outputs:

// Comment.
main() {}

This is different from the current style where it will preserve a blank line after a comment and the thing that follows it. This is particularly common to separate the initial copyright comment from subsequent code:

// Copyright (c) 2022, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

import 'package:analyzer/dart/ast/ast.dart';

Should the new style do that? I suspect the answer is yes.

cc @natebosch @kallentu

[jakemac53]

Are there any situations other than the top level header where we do this? If not, should we just specialize the behavior up until the first non-comment (or is that feasible)?

[kallentu]

Are there any situations other than the top level header where we do this? If not, should we just specialize the behavior up until the first non-comment (or is that feasible)?

+1

Removing blank lines between comments and top level code is probably fine? I anecdotally never see code that has really used that feature, besides the exception of the copyright header and the next code line. (But it would be good to get that working.)

[srawlins]

I see often in large files separations like "// something or other methods" and "// fields for such and such" and "// constructors."

If a comment was previously separated from the thing after it, by a blank line, and suddenly becomes quite attached to the very next element, I can see confusion ensuing.

[srawlins]

Here is a good code search query to look at top-level examples in google3: lang:dart \n//\s.*\n\n pcre:yes; that catches the last line of a lot of copyright notices. lang:dart \n\n//\s.*\n\n pcre:yes catches single-line comments. You can tweak it for two-line comments, or comments indented two spaces.

[kallentu]

Ah, I stand corrected. People do use standalone comments for categorizing.

Preserving blank lines between comments & top level code 👍