demo: added intentional bug for Qodo Merge review

[Jsihra]

User description

Qodo Merge Demo: introduce minor bug for review

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PR Type

Bug fix, Tests

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Description

• Added calculator module with intentional off-by-one bug

• Demonstrates bug in sum_numbers function for code review

• Includes average function without error handling

• Updated README with demo project header

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Diagram Walkthrough

flowchart LR
  A["README.md<br/>Project header"] --> B["calculator.py<br/>New module"]
  B --> C["sum_numbers<br/>Off-by-one bug"]
  B --> D["average<br/>No error handling"]

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File Walkthrough

	Relevant files
Documentation	README.md Add project header comment                                                              README.md Added blank line after project title Added comment header '#hello' +2/-0
Bug fix	calculator.py New calculator module with intentional bugs                            calculator.py Created new calculator module with three functions sum_numbers function contains intentional off-by-one error in loop range average function lacks error handling for empty lists Added main function demonstrating both functions with sample data +22/-0

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[qodo-code-review]

PR Compliance Guide 🔍

Below is a summary of compliance checks for this PR:

Security Compliance
🔴	Out-of-bounds access Description: Loop iterates to len(numbers) + 1 causing out-of-range indexing at numbers[i], which can crash the program or expose behavior differences based on input length. calculator.py [5-6] Referred Code for i in range(len(numbers) + 1): total += numbers[i]
Ticket Compliance
⚪	🎫 No ticket provided Create ticket/issue
Codebase Duplication Compliance
⚪	Codebase context is not defined Follow the guide to enable codebase context checks.
Custom Compliance
🟢	Generic: Meaningful Naming and Self-Documenting Code Objective: Ensure all identifiers clearly express their purpose and intent, making code self-documenting Status: Passed
	Generic: Secure Logging Practices Objective: To ensure logs are useful for debugging and auditing without exposing sensitive information like PII, PHI, or cardholder data. Status: Passed
🔴	Generic: Robust Error Handling and Edge Case Management Objective: Ensure comprehensive error handling that provides meaningful context and graceful degradation Status: Missing edge handling: The average function lacks handling for empty lists and sum_numbers has an off-by-one bug that will raise IndexError without contextual handling. Referred Code for i in range(len(numbers) + 1): total += numbers[i] return total def average(numbers): """Return the average of numbers (no error handling for empty list).""" return sum(numbers) / len(numbers) def main(): data = [10, 20, 30, 40, 50] print("Sum:", sum_numbers(data)) print("Average:", average(data))
⚪	Generic: Comprehensive Audit Trails Objective: To create a detailed and reliable record of critical system actions for security analysis and compliance. Status: No audit logs: The new functions perform actions without any auditing or logging context, but it is unclear whether these operations are considered critical in this application. Referred Code def sum_numbers(numbers): """Return the sum of all numbers in the list.""" total = 0 # ❌ Intentional bug: off-by-one error (should be range(len(numbers))) for i in range(len(numbers) + 1): total += numbers[i] return total def average(numbers): """Return the average of numbers (no error handling for empty list).""" return sum(numbers) / len(numbers) def main(): data = [10, 20, 30, 40, 50] print("Sum:", sum_numbers(data)) print("Average:", average(data)) if __name__ == "__main__": ... (clipped 1 lines)
	Generic: Secure Error Handling Objective: To prevent the leakage of sensitive system information through error messages while providing sufficient detail for internal debugging. Status: Unhandled exceptions: Unhandled IndexError or ZeroDivisionError could surface raw exceptions depending on the runtime environment, but the code here does not itself format or expose sensitive error details. Referred Code for i in range(len(numbers) + 1): total += numbers[i] return total def average(numbers): """Return the average of numbers (no error handling for empty list).""" return sum(numbers) / len(numbers) def main(): data = [10, 20, 30, 40, 50] print("Sum:", sum_numbers(data)) print("Average:", average(data))
	Generic: Security-First Input Validation and Data Handling Objective: Ensure all data inputs are validated, sanitized, and handled securely to prevent vulnerabilities Status: No input validation: Functions accept external lists without validating types or emptiness, but given this is a simple local computation module it is unclear if external/untrusted input is expected. Referred Code def sum_numbers(numbers): """Return the sum of all numbers in the list.""" total = 0 # ❌ Intentional bug: off-by-one error (should be range(len(numbers))) for i in range(len(numbers) + 1): total += numbers[i] return total def average(numbers): """Return the average of numbers (no error handling for empty list).""" return sum(numbers) / len(numbers) def main(): data = [10, 20, 30, 40, 50] print("Sum:", sum_numbers(data)) print("Average:", average(data))

Compliance status legend

🟢 - Fully Compliant
🟡 - Partial Compliant
🔴 - Not Compliant
⚪ - Requires Further Human Verification
🏷️ - Compliance label

[qodo-code-review]

PR Code Suggestions ✨

Explore these optional code suggestions:

Category	Suggestion	Impact
Possible issue	Fix index out-of-bounds error Correct the loop range in sum_numbers from range(len(numbers) + 1) to range(len(numbers)) to prevent an IndexError. calculator.py [5-6] -for i in range(len(numbers) + 1): +for i in range(len(numbers)): total += numbers[i] Apply / Chat Suggestion importance[1-10]: 10 __ Why: This suggestion correctly identifies a critical off-by-one error in the loop that will cause an IndexError and crash the sum_numbers function, making it unusable.	High
	Prevent division by zero error Add a check in the average function to handle empty lists and prevent a ZeroDivisionError, for example by returning 0. calculator.py [10-12] def average(numbers): - """Return the average of numbers (no error handling for empty list).""" + """Return the average of numbers.""" + if not numbers: + return 0 return sum(numbers) / len(numbers) Apply / Chat Suggestion importance[1-10]: 8 __ Why: The suggestion correctly points out that the average function will crash with a ZeroDivisionError if given an empty list and proposes a valid fix to handle this edge case.	Medium
High-level	Avoid merging intentionally buggy demo code Avoid merging intentionally buggy demo code into the main branch, as it pollutes the codebase. Instead, use the PR for demonstration purposes and then either close it without merging or fix the bugs before completion. Examples: calculator.py [1-22] def sum_numbers(numbers): """Return the sum of all numbers in the list.""" total = 0 # ❌ Intentional bug: off-by-one error (should be range(len(numbers))) for i in range(len(numbers) + 1): total += numbers[i] return total def average(numbers): ... (clipped 12 lines) Solution Walkthrough: Before: # calculator.py def sum_numbers(numbers): """Return the sum of all numbers in the list.""" total = 0 # ❌ Intentional bug: off-by-one error for i in range(len(numbers) + 1): total += numbers[i] return total def average(numbers): """Return the average of numbers (no error handling for empty list).""" return sum(numbers) / len(numbers) After: # The suggestion is to not merge the code, or to fix it. # The fixed code would look like this: def sum_numbers(numbers): """Return the sum of all numbers in the list.""" # Fix: Use correct range or built-in sum() return sum(numbers) def average(numbers): """Return the average of numbers.""" # Fix: Add error handling for empty list if not numbers: return 0 return sum(numbers) / len(numbers) Suggestion importance[1-10]: 9 __ Why: This is an excellent high-level suggestion that addresses the process and long-term health of the codebase, correctly identifying the risk of merging intentionally buggy code.	High
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