BRO1526: Blank line between switch sections

The sections of a switch statement are separated by a blank line, or (if you configure it) not. Not a StyleCop rule: from Roslynator's RCS0061.

Example

Before

public static class Shipping
{
    public static decimal Cost(string zone, decimal weight)
    {
        switch (zone)
        {
            case "local":
                return 5m;
            case "national":
            case "island":
                return 5m + weight;
            default:
                return 20m + (2 * weight);
        }
    }
}

After

public static class Shipping
{
    public static decimal Cost(string zone, decimal weight)
    {
        switch (zone)
        {
            case "local":
                return 5m;

            case "national":
            case "island":
                return 5m + weight;

            default:
                return 20m + (2 * weight);
        }
    }
}

Why

A long switch reads like a list of small blocks. A blank line between them shows where one case ends and the next begins, the way BRO1505 separates members. Some teams prefer compact sections; the option is for them.

Configuration

[*.cs]
stylebro_blank_line_between_switch_sections = include

• include (default): one blank line between sections.
• omit: no blank line between sections.
• omit_after_block: a blank line, except after a section whose last statement is a block (case 1: { ... }).

Labels of one section (case 2: and case 3: above) belong together and are never separated. Several blank lines between sections are BRO1517's, which leaves one.

How the fix works

It adds a line break before the next section's first label, or removes the blank lines there.

After a multi-line block (a section that ends in { ... }, or in an if/else whose last } closes the section) the setting decides too: where it wants no blank line (omit, or omit_after_block after a { ... } section), BRO1519 doesn't ask for one after the }, and BRO1504 doesn't ask for one above a comment that starts the next section. Where it wants one (include), BRO1519 wants the same and this rule leaves that gap to it.

Not reported

• A comment or directive between the sections: the blank line may belong to the comment (BRO1504), and an #if can hide sections. A trailing comment after the previous section's last statement is fine.
• Sections on one line (case 1: return 1; case 2: return 2;).
• Switch expressions: their arms aren't sections.
• Code with syntax errors in the switch.

Compared with StyleCop

StyleCop has no such rule; its SA1513 (StyleBro's BRO1519) only asks for a blank line after a }. stylebro-migrate turns this rule off, so migrating doesn't change a StyleCop-clean repository.