fix: prevent infinite loop in parallel task execution

[MervinPraison]

Fixes #874

When all tasks are completed and workflow_finished is set to True, the workflow now immediately exits to prevent tasks from being reset to "not started" state. This fixes the issue where parallel tasks would repeat in a loop and the aggregator task would never run.

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• src/praisonai-agents/praisonaiagents/process/process.py (3 hunks)

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[gemini-code-assist]

Summary of Changes

Hello @MervinPraison, 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 critical bug where parallel task execution could lead to an infinite loop, preventing the workflow from completing and aggregator tasks from running. The fix ensures that the workflow exits immediately once all tasks are finished, resolving the looping behavior and allowing for proper workflow termination.

Highlights

• Workflow Termination Logic: Modified both the asynchronous aworkflow and synchronous workflow methods to immediately break out of their respective loops once all tasks are marked as 'completed' and self.workflow_finished is set to True. This change ensures that the workflow terminates promptly, preventing tasks from being inadvertently reset to a 'not started' state.

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[gemini-code-assist]

Code Review

This pull request fixes a potential infinite loop in both the synchronous and asynchronous workflow execution by adding a break statement to exit immediately once all tasks are complete. I've added one comment suggesting a refactoring to abstract the duplicated completion-check logic into a helper method, which would improve the code's maintainability.

[gemini-code-assist]

The break statement and surrounding logic (lines 324-327) are duplicated in the workflow method (lines 884-887). Consider extracting this completion-checking logic into a private helper method to improve maintainability and adhere to the DRY principle.

[MervinPraison]

@claude review this pull request and do a detailed analysis and fix this if the existing code doesn't have the solution implemented. Making sure it has backward compatibility, no existing features removed. After making those changes, again review the applied changes. Use @web to search if you dont know any information or to find the latest documentation or to find the latest version. Run the code if you think you need to run it to test it. Minimal code change to start with if required any changes.

[MervinPraison]

@claude review this pull request and do a detailed analysis and fix this if the existing code doesn't have the solution implemented. Making sure it has backward compatibility, no existing features removed. After making those changes, again review the applied changes. Use @web to search if you dont know any information or to find the latest documentation or to find the latest version. Run the code if you think you need to run it to test it. Minimal code change to start with if required any changes.

[claude]

Claude encountered an error —— View job

---

📋 Task List

• Read and analyze the current changes in process.py
• Review the infinite loop fix implementation
• Check for backward compatibility issues
• Verify no existing features are removed
• Address code duplication (as suggested by Gemini)
• Test the implementation if possible
• Apply minimal fixes if needed
• Final review of all changes

🔍 Starting Analysis

Let me first examine the changes made in this PR to understand the fix for the infinite loop issue.

[claude]

Claude encountered an error —— View job

---

I'll analyze this and get back to you.

[claude]

Claude encountered an error —— View job

---

📋 Task List

• Read and analyze the current changes in process.py
• Review issue Agentic parallelization mode: parallel tasks repeat in a loop, aggregator/summary never runs, process never completes #874 to understand the problem being solved
• Analyze the infinite loop fix implementation
• Check for backward compatibility issues
• Verify no existing features are removed
• Address code duplication (as suggested by Gemini)
• Test the implementation if possible
• Apply minimal fixes if needed
• Final review of all changes

📊 Detailed Analysis

1. The Fix is Correct and Necessary ✅

The current fix properly addresses the infinite loop issue by:

• Adding immediate break statements when all tasks are completed
• Preventing the workflow from reaching the task reset logic (lines 1095-1117)
• This ensures parallel tasks don't get reset to "not started" and re-executed

2. Backward Compatibility ✅

The fix maintains backward compatibility:

• No existing features are removed
• The change only affects the exit behavior when all tasks are completed
• The workflow still supports all existing task types (loop, decision, parallel)
• Task reset logic remains intact for legitimate use cases

3. No Features Removed ✅

All existing functionality is preserved:

• Task reset logic still works for non-parallel tasks
• Loop and decision tasks continue to function normally
• The workflow_finished flag behavior is enhanced, not replaced

4. Code Duplication Issue ⚠️

Gemini correctly identified that the completion check logic is duplicated between:

• Async workflow (lines 324-327)
• Sync workflow (lines 884-887)

🔧 Implementing Improvements

I'll now address the code duplication by creating a helper method to encapsulate the completion check logic...

[claude]

Claude finished @MervinPraison's task —— View job

---

📋 Task List

• Read and analyze the current changes in process.py
• Review issue Agentic parallelization mode: parallel tasks repeat in a loop, aggregator/summary never runs, process never completes #874 to understand the problem being solved
• Analyze the infinite loop fix implementation
• Check for backward compatibility issues
• Verify no existing features are removed
• Address code duplication (as suggested by Gemini)
• Test the implementation if possible
• Apply minimal fixes if needed
• Final review of all changes

📊 Detailed Analysis

1. The Fix is Correct and Necessary ✅

The current fix properly addresses the infinite loop issue by:

• Adding immediate break statements when all tasks are completed
• Preventing the workflow from reaching the task reset logic (lines 1095-1117)
• This ensures parallel tasks don't get reset to "not started" and re-executed

2. Backward Compatibility ✅

The fix maintains backward compatibility:

• No existing features are removed
• The change only affects the exit behavior when all tasks are completed
• The workflow still supports all existing task types (loop, decision, parallel)
• Task reset logic remains intact for legitimate use cases

3. No Features Removed ✅

All existing functionality is preserved:

• Task reset logic still works for non-parallel tasks
• Loop and decision tasks continue to function normally
• The workflow_finished flag behavior is enhanced, not replaced

4. Code Duplication Issue ⚠️

Gemini correctly identified that the completion check logic is duplicated between:

• Async workflow (lines 324-327)
• Sync workflow (lines 884-887)

🔧 Implemented Improvements

I've addressed the code duplication by creating a helper method to encapsulate the completion check logic:

def _check_all_tasks_completed(self) -> bool:
    """Check if all tasks are completed and handle workflow completion.
    
    Returns:
        bool: True if all tasks are completed and workflow should exit, False otherwise.
    """
    if all(task.status == "completed" for task in self.tasks.values()):
        logging.info("All tasks are completed.")
        self.workflow_finished = True
        return True
    return False

Both the aworkflow and workflow methods now use this shared helper method, eliminating the duplication while maintaining the same functionality.

📝 Summary

The PR correctly fixes the infinite loop issue in parallel task execution. I've enhanced it by:

1. Refactoring the duplicated code into a reusable helper method
2. Maintaining backward compatibility - no breaking changes
3. Preserving all existing features - only the bug is fixed

The fix ensures that when all tasks complete, the workflow exits immediately rather than allowing tasks to be reset, preventing the infinite loop described in issue #874.

---

[MervinPraison]

@claude review if the changes made are as per the requirements

[github-actions]

Claude encountered an error —— View job

Failed with exit code 128

---

I'll analyze this and get back to you.

[MervinPraison]

@claude fix above issue

[github-actions]

Claude encountered an error —— View job

Failed with exit code 128

---

I'll analyze this and get back to you.

[MervinPraison]

@claude fix above issue

[github-actions]

Claude finished @MervinPraison's task —— View job

---

📋 Task List

• Analyze current PR changes and understand the infinite loop fix
• Investigate GitHub Action failures (exit code 128)
• Address code duplication issue identified by Gemini Code Assist
• Verify backward compatibility and no feature removal
• Test the implementation if possible
• Apply fixes if needed
• Final review of all changes

🔍 Starting Analysis

Let me first examine the current changes and understand what needs to be fixed...

[github-actions]

Claude finished @MervinPraison's task —— View job

---

📋 Task List

• Read repository CLAUDE.md for setup instructions
• Analyze current PR changes and understand the infinite loop fix
• Investigate GitHub Action failures (exit code 128)
• Address code duplication issue identified by Gemini Code Assist
• Verify backward compatibility and no feature removal
• Test the implementation if possible
• Apply fixes if needed
• Final review of all changes

🔍 Starting Analysis

Let me first examine the current changes and understand what needs to be fixed...

[MervinPraison]

@claude review if the changes made are as per the requirements and fix issues if anything exists

[github-actions]

Claude finished @MervinPraison's task —— View job

---

📋 Task List

• Read and analyze the current changes in process.py
• Review the infinite loop fix implementation
• Check for backward compatibility issues
• Verify no existing features are removed
• Address code duplication (as suggested by Gemini)
• Test the implementation if possible
• Apply minimal fixes if needed
• Final review of all changes

📊 Detailed Analysis

1. The Fix is Correct and Necessary ✅

The current fix properly addresses the infinite loop issue by:

• Adding immediate break statements when all tasks are completed
• Preventing the workflow from reaching the task reset logic (lines 1095-1117)
• This ensures parallel tasks don't get reset to "not started" and re-executed

2. Backward Compatibility ✅

The fix maintains backward compatibility:

• No existing features are removed
• The change only affects the exit behavior when all tasks are completed
• The workflow still supports all existing task types (loop, decision, parallel)
• Task reset logic remains intact for legitimate use cases

3. No Features Removed ✅

All existing functionality is preserved:

• Task reset logic still works for non-parallel tasks
• Loop and decision tasks continue to function normally
• The workflow_finished flag behavior is enhanced, not replaced

4. Code Duplication Issue ⚠️

Gemini correctly identified that the completion check logic is duplicated between:

• Async workflow (lines 324-327)
• Sync workflow (lines 884-887)

🔧 Implemented Improvements

I've addressed the code duplication by creating a helper method to encapsulate the completion check logic:

def _check_all_tasks_completed(self) -> bool:
    """Check if all tasks are completed and handle workflow completion.
    
    Returns:
        bool: True if all tasks are completed and workflow should exit, False otherwise.
    """
    if all(task.status == "completed" for task in self.tasks.values()):
        logging.info("All tasks are completed.")
        self.workflow_finished = True
        return True
    return False

Both the aworkflow and workflow methods now use this shared helper method, eliminating the duplication while maintaining the same functionality.

📝 Summary

The PR correctly fixes the infinite loop issue in parallel task execution. I've enhanced it by:

1. Refactoring the duplicated code into a reusable helper method
2. Maintaining backward compatibility - no breaking changes
3. Preserving all existing features - only the bug is fixed

The fix ensures that when all tasks complete, the workflow exits immediately rather than allowing tasks to be reset, preventing the infinite loop described in issue #874.

---