Comparison with a boolean constant (CompareWithBoolean)¶

Type	Scope	Severity	Activated by default	Minutes to fix	Tags
`Code smell`	`BSL` `OS`	`Minor`	`Yes`	`1`	`clumsy` `suspicious`

Description¶

Comparing an expression with the boolean constant True or False using the = and <> operators is redundant and reduces code readability. If the expression already has the Boolean type, it is enough to use it directly (or with the NOT operator).

Moreover, such a construction can hide a design error: if for some reason the type of the expression differs from Boolean, the code branch may be executed incorrectly.

Examples¶

Bad:

If Value = True Then
    // ...
EndIf;

If Value <> False Then
    // ...
EndIf;

Good:

If Value Then
    // ...
EndIf;

If NOT Value Then
    // ...
EndIf;

Exceptions¶

The diagnostic is triggered only if the type of the second operand can be inferred and it is unambiguously Boolean. If the type cannot be determined or is a union of types, no issue is reported — in such cases comparison with a boolean constant may be justified.

For example, SafeMode() returns a value of type Boolean | String, so comparison with False is correct here and no issue is reported:

If SafeMode() <> False Then
    // ...
EndIf;

Sources¶

Standard: Comparison with True and False (RU) (item 4)

Snippets¶

Diagnostic ignorance in code¶

// BSLLS:CompareWithBoolean-off
// BSLLS:CompareWithBoolean-on

Parameter for config¶

"CompareWithBoolean": false