New rule proposal: Curly braces must not be omitted when parent expression spans multiple lines

[alxru]

Category: Layout
Rule: Curly braces must not be omitted when parent expression spans multiple lines.
Rationale: Improve readability and maintainability of the code (when SA1503 is off).
See also: SA1503:CurlyBracketsMustNotBeOmitted and SA1519:CurlyBracketsMustNotBeOmittedFromMultiLineChildStatement

Bad:

if (alpha == beta &&
    beta == gamma)
    alpha = delta;

Good:

if (alpha == beta &&
    beta == gamma)
{
    alpha = delta;
}

[sharwell]

I think I'd be more in favor of modifying rule SA1519 to perform a combination of this and what it currently does. Something like "Curly braces must not be omitted when clause spans more than two lines". In addition to the case above, this would finally cover the following case:

do
    Method(); // SA1519
while (condition);

📝 I used the term clause because technically the following is one statement:

if (condition)
    Then();
else
    Else();

[alxru]

It would be ok to extend SA1519 but I'm not sure that this should affect the do-while loops -- short do-whiles will get two lines longer then:

do
{
    Method();
}
while (condition);

And sometimes there's a need to just transform a while-do loop to a do-while loop. With the new behavior, moving the loop condition to the end of the loop would require adding {} to the code (and a separate line for each of the braces).

[jnm2]

@sharwell So SA1519:CurlyBracketsMustNotBeOmittedFromMultiLineChildStatement would change to CurlyBracketsMustNotBeOmittedWhenConditionOrChildStatementIsMultiLine and start giving more warnings than it did in previous versions?

[sharwell]

@jnm2 Yes that's correct

[jnm2]

Hmm, the term 'condition' isn't generic enough since we have to handle using and for statements.
'Parenthesized syntax' is too long and hard to understand. Also, we care about more than just the parenthesized part:

if
    (cond)
    return;

What's a term that means 'the part before the child statement'?