> ## Documentation Index
> Fetch the complete documentation index at: https://ancplua.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# AL0042 - AotTest should return 100

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

Source: [AL0042AotTestExitCode100Analyzer.cs](https://github.com/ANcpLua/ANcpLua.Analyzers/blob/main/src/ANcpLua.Analyzers/Analyzers/AL0042AotTestExitCode100Analyzer.cs)

## Description

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

## Bad Code

```csharp theme={null}
[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

```csharp theme={null}
[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

```editorconfig theme={null}
dotnet_diagnostic.AL0042.severity = warning
```

## Exit Code Convention

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