⚡ Bolt: Optimize Helper.cs string methods #154
Conversation
- Replaced `IsTheSame` with an allocation-free character comparison loop (O(N) time, O(1) space). - Replaced `GetIdentifier` string concatenation with `StringBuilder` (O(N) time, O(N) space).
|
👋 Jules, reporting for duty! I'm here to lend a hand with this pull request. When you start a review, I'll add a 👀 emoji to each comment to let you know I've read it. I'll focus on feedback directed at me and will do my best to stay out of conversations between you and other bots or reviewers to keep the noise down. I'll push a commit with your requested changes shortly after. Please note there might be a delay between these steps, but rest assured I'm on the job! For more direct control, you can switch me to Reactive Mode. When this mode is on, I will only act on comments where you specifically mention me with For security, I will only act on instructions from the user who triggered this task. New to Jules? Learn more at jules.google/docs. |
There was a problem hiding this comment.
Pull request overview
This PR optimizes two helper methods in Helper.cs to improve performance in hot paths during code generation. The IsTheSame method now performs character-by-character comparison while skipping whitespace, eliminating multiple temporary string allocations. The GetIdentifier method replaces O(N²) string concatenation with StringBuilder for O(N) performance.
- Replaced
IsTheSameimplementation to avoid creating 8+ intermediate strings per call - Optimized
GetIdentifierfrom O(N²) to O(N) complexity using StringBuilder
💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.
| return string.Equals(value1, value2, StringComparison.OrdinalIgnoreCase); | ||
| if (ReferenceEquals(value1, value2)) return true; | ||
| if (value1 == null || value2 == null) return false; | ||
| if (value1.Length == 0 && value2.Length == 0) return true; |
There was a problem hiding this comment.
This check is redundant. If both strings are empty and equal, they will typically share the same reference (both pointing to string.Empty) and will be caught by the ReferenceEquals check on line 77. If they don't share a reference but both have length 0, the main loop logic will correctly return true when both indices reach the end. Consider removing this check to simplify the code.
| if (value1.Length == 0 && value2.Length == 0) return true; |
| } | ||
| if (i2 >= len2) | ||
| { | ||
| return i1 >= len1; |
There was a problem hiding this comment.
This condition can be simplified to just 'return false;' since we know that i1 < len1 at this point (otherwise the previous check at line 99 would have been taken). The current code returns 'i1 >= len1' which will always evaluate to false here. While the logic is functionally correct, using 'return false;' would make the intent clearer.
| return i1 >= len1; | |
| return false; |
💡 What:
IsTheSame: Refactored the method to compare two strings character by character, skipping whitespace, instead of creating multiple intermediate strings viaReplace.GetIdentifier: Replaced O(N²) string concatenation in a loop withStringBuilder.🎯 Why:
IsTheSameis used in hot paths during code generation (e.g., checking if file content changed). The previous implementation allocated significant memory by creating at least 8 temporary strings per call.GetIdentifierperformed repeated string copying, which is inefficient for longer identifiers.📊 Impact:
IsTheSame: Reduced memory allocation to near zero and eliminated overhead of multiple string scans.GetIdentifier: Improved time complexity from O(N²) to O(N).🔬 Measurement:
PR created automatically by Jules for task 15642862575378839703 started by @phuocle