Remove unnecessary suppression (IDE0079)
Property | Value |
---|---|
Rule ID | IDE0079 |
Title | Remove unnecessary suppression |
Category | CodeQuality |
Subcategory | Unnecessary code rules (suppression preferences) |
Applicable languages | C# and Visual Basic |
Options | dotnet_remove_unnecessary_suppression_exclusions |
Overview
This rule flags unnecessary pragma and SuppressMessageAttribute attribute suppressions in source.
Source suppressions suppress violations of compiler and analyzer rules in specific places but not in other parts of the source code. You generally use them to suppress false positives or less important violations that you don't intend to fix. However, suppressions often become stale. This can happen if a rule is fixed to prevent false positives or you refactor your code and, in doing so, render the suppressions redundant. This rule helps to identify redundant suppressions, which can be removed.
Note
Even if you enable code style rules on build, this rule is not enabled. It only surfaces in the Visual Studio editor.
Example
using System.Diagnostics.CodeAnalysis;
class C1
{
// Necessary pragma suppression
#pragma warning disable IDE0051 // IDE0051: Remove unused member
private int UnusedMethod() => 0;
#pragma warning restore IDE0051
// IDE0079: Unnecessary pragma suppression
#pragma warning disable IDE0051 // IDE0051: Remove unused member
private int UsedMethod() => 0;
#pragma warning restore IDE0051
public int PublicMethod() => UsedMethod();
}
class C2
{
// Necessary SuppressMessage attribute suppression
[SuppressMessage("CodeQuality", "IDE0051:Remove unused private members", Justification = "<Pending>")]
private int _unusedField;
// IDE0079: Unnecessary SuppressMessage attribute suppression
[SuppressMessage("CodeQuality", "IDE0051:Remove unused private members", Justification = "<Pending>")]
private int _usedField;
public int PublicMethod2() => _usedField;
}
Options
Options specify the behavior that you want the rule to enforce. For information about configuring options, see Option format.
dotnet_remove_unnecessary_suppression_exclusions
Property | Value | Description |
---|---|---|
Option name | dotnet_remove_unnecessary_suppression_exclusions | |
Option values | , separated list of rule IDs or categories (prefixed with category: ) |
Excludes suppressions for the listed rules |
all |
Disables the rule (all rule IDs excluded) | |
none |
Enables the rule for all rules (no exclusions) | |
Default option value | none |
using System.Diagnostics.CodeAnalysis;
class C1
{
// 'dotnet_remove_unnecessary_suppression_exclusions = IDE0051'
// Unnecessary pragma suppression, but not flagged by IDE0079
#pragma warning disable IDE0051 // IDE0051: Remove unused member
private int UsedMethod() => 0;
#pragma warning restore IDE0051
public int PublicMethod() => UsedMethod();
}
Suppress a warning
If you want to suppress only a single violation, add preprocessor directives to your source file to disable and then re-enable the rule.
#pragma warning disable IDE0079
// The code that's violating the rule is on this line.
#pragma warning restore IDE0079
To disable the rule for a file, folder, or project, set its severity to none
in the configuration file.
[*.{cs,vb}]
dotnet_diagnostic.IDE0079.severity = none
To disable this entire category of rules, set the severity for the category to none
in the configuration file.
[*.{cs,vb}]
dotnet_analyzer_diagnostic.category-CodeQuality.severity = none
For more information, see How to suppress code analysis warnings.