Fix: Add regex comparison support to Condition Agentflow

[shazee257]

Fixes #5650 - - Bug: "Regex" operation in Condition node is not implemented in backend

The Condition Agentflow node exposes a Regex operation in the UI but the backend did not implement it, causing runtime errors during evaluation. This update adds the missing backend behavior and ensures regex conditions evaluate safely.

• Backend condition evaluation

  • Added a regex comparator with defensive limits and invalid-pattern handling to prevent runtime errors and mitigate expensive pattern evaluation.

• Tests

  • Added unit coverage for regex match, invalid patterns, and safety limit enforcement.

Example:

const isMatch = compareOperationFunctions.regex('Hello123', '^Hello\\d+$')
// → true

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Original prompt

read the issue at #5650 and create new pull request with description , fix it

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[gemini-code-assist]

Summary of Changes

Hello @shazee257, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request addresses a functional gap in the Condition Agentflow node by providing a robust backend implementation for regex comparisons. It ensures that users can safely and effectively utilize regular expressions within their agent flows, preventing previous runtime errors and enhancing the node's conditional logic capabilities.

Highlights

• Regex Comparison Support: Implemented the missing backend logic for the 'regex' operation in the Condition Agentflow node, which was previously only exposed in the UI, resolving runtime errors during evaluation.
• Robustness and Safety: The new regex comparator includes defensive limits for pattern and input string lengths (256 and 10000 characters respectively) and handles invalid regex patterns gracefully to prevent runtime errors and mitigate expensive pattern evaluations.
• Comprehensive Testing: Added new unit tests to cover successful regex matches, scenarios with invalid regex patterns, and cases where safety limits are exceeded, ensuring the reliability of the new functionality.

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[gemini-code-assist]

Code Review

This pull request correctly implements the missing regex operation for the Condition Agentflow node, including important safety checks to prevent runtime errors and expensive evaluations. The addition of unit tests is also great for ensuring the new functionality is robust. My feedback includes suggestions to improve code readability by using named constants, enhancing type safety in the tests, and expanding test coverage to include all safety checks.

[Copilot]

Pull request overview

This PR fixes a critical bug where the Condition Agentflow node exposed a "Regex" operation in the UI but lacked the corresponding backend implementation, causing runtime errors when users attempted to use this feature.

Changes:

• Added regex comparator implementation with defensive safety limits (256 char pattern, 10,000 char input) and error handling for invalid patterns
• Added comprehensive unit tests covering successful regex matching, invalid pattern handling, and safety limit enforcement

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 4 comments.

File	Description
packages/components/nodes/agentflow/Condition/Condition.ts	Implements the missing regex comparison function with safety limits and error handling
packages/components/nodes/agentflow/Condition/Condition.test.ts	Adds new test suite with three test cases covering regex functionality, invalid patterns, and safety limits

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