AL0042 - AotTest should return 100

[AotTest]/[TrimTest] methods should return 100 on success by convention

Source: AL0042AotTestExitCode100Analyzer.cs

Description

By convention, AOT/Trim test methods should return 100 to indicate success. Other values are reserved for failure conditions.

Bad Code

[AotTest]
public int TestMethod() {
    // Test logic
    return 0;  // Warning: use 100 for success
}

[TrimTest]
public static int RunTest() {
    return 1;  // Warning: non-standard success code
}

Good Code

[AotTest]
public int TestMethod() {
    // Test logic
    return 100;  // Convention: 100 = success
}

[TrimTest]
public static int RunTest() {
    try {
        // Test logic
        return 100;  // Success
    } catch {
        return 1;  // Failure
    }
}

Properties

• Category: Usage
• Severity: Warning
• Enabled by default: True
• Code fix available: False

Configuration

dotnet_diagnostic.AL0042.severity = warning

Exit Code Convention

Code	Meaning
100	Success
1-99	Test failure (specific error codes)
101+	Test infrastructure error