Potential fix for code scanning alert no. 87: String concatenation in loop #1003
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… loop use string builder to combine strings in a loop Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>
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Pull Request Overview
This PR addresses a code scanning alert by replacing inefficient string concatenation in a loop with a StringBuilder. The change optimizes the performance of message construction when building method signatures for logging purposes.
Key Changes
- Replaces string concatenation with
StringBuilderfor building method signatures - Adds proper
using System.Text;import statement - Improves performance by avoiding repeated string allocations in loops
| var message = messageBuilder.ToString(); | ||
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| } |
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The variable message is declared inside the if block but used outside of it at line 204. This will cause a compilation error because message is not in scope when parameters.Length is 0. Move the declaration outside the if block or ensure it's accessible in all code paths.
| var message = messageBuilder.ToString(); | |
| } | |
| } | |
| message = messageBuilder.ToString(); |
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| if (parameters.Length > 0) | ||
| messageBuilder.Length -= 1; |
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This condition check is redundant since this code is already inside a block that only executes when parameters.Length > 0 (line 183). The condition will always be true and can be removed.
| if (parameters.Length > 0) | |
| messageBuilder.Length -= 1; | |
| messageBuilder.Length -= 1; |
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Added line breaks and formatting adjustments to enhance clarity. Reformatted comments and logging statements for consistency. No functional changes were made; the code is now more maintainable.
| var vmType = viewModel.GetType(); | ||
| if (vmType.FullName == "Microsoft.Expression.DesignModel.InstanceBuilders.DesignInstanceExtension") { | ||
| if (vmType.FullName == "Microsoft.Expression.DesignModel.InstanceBuilders.DesignInstanceExtension") |
Check warning
Code scanning / CodeQL
Erroneous class compare Warning
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AI 2 days ago
To fix the problem, replace the string-based type comparison (vmType.FullName == "Microsoft.Expression.DesignModel.InstanceBuilders.DesignInstanceExtension") with a direct type comparison using == typeof(...). This ensures that the check is robust and not vulnerable to spoofing by types with the same name in different assemblies. The change should be made only in the relevant region (line 249) of src/Caliburn.Micro.Platform/ViewModelBinder.cs. No new imports are needed, as typeof is a built-in C# operator.
| @@ -246,7 +246,7 @@ | ||
| if (View.InDesignMode) | ||
| { | ||
| var vmType = viewModel.GetType(); | ||
| if (vmType.FullName == "Microsoft.Expression.DesignModel.InstanceBuilders.DesignInstanceExtension") | ||
| if (vmType == Type.GetType("Microsoft.Expression.DesignModel.InstanceBuilders.DesignInstanceExtension", false)) | ||
| { | ||
| var propInfo = vmType.GetProperty("Instance", BindingFlags.Instance | BindingFlags.NonPublic); | ||
| viewModel = propInfo.GetValue(viewModel, null); |
Potential fix for https://github.com/Caliburn-Micro/Caliburn.Micro/security/code-scanning/87
To fix the problem, replace the string concatenation in the loop with a
StringBuilder. Specifically, in the region wheremessageis built up by appending parameter names and commas, instantiate aStringBuilder, append the method name, and then append each parameter name and comma inside the loop. After the loop, remove the trailing comma and append the closing parenthesis. Finally, convert theStringBuilderto a string and assign it tomessage. This change should be made in the block starting at line 179, wheremessageis constructed. You will need to addusing System.Text;at the top of the file if it is not already present.Suggested fixes powered by Copilot Autofix. Review carefully before merging.