Proposal: relax parenthesis usage (AV2400)

[bkoelman]

Existing guidance:

Add parentheses around every binary expression, but don’t add parentheses around unary expressions. For example if (!string.IsNullOrEmpty(str) && (str != "new"))

Most developers are unaware that && has higher precedence than ||, which makes expressions like below hard to read:

if (a && b || c)
{
}

For other cases I think precedence is obvious for most developers:

if (a > b && c < d)
{
}

int result = a + b * c;

Recently the usage of parentheses was added to Visual Studio / .editorconfig:

# Parentheses preferences
dotnet_style_parentheses_in_arithmetic_binary_operators = always_for_clarity:silent
dotnet_style_parentheses_in_other_binary_operators = always_for_clarity:silent
dotnet_style_parentheses_in_other_operators = never_if_unnecessary:silent
dotnet_style_parentheses_in_relational_binary_operators = always_for_clarity:silent

and to Resharper:

This enables us to be more specific on which cases parentheses are helpful and have automated formatting settings for them.

[dennisdoomen]

So how would you change the rule?

[bkoelman]

Remove redundant parentheses in expressions if they do not clarify precedence. Add parentheses in expressions to avoid non-obvious precedence. For example, in nested conditional expressions: overruled || (enabled && active), bitwise and shift operations: foo | (bar >> size).

[dennisdoomen]

I think that's a good balance.