Add Unit Tests for Scanner Runner Implementation

[knakul853]

Issue Description

The pkg/runner/runner.go file, which contains the core scanning functionality of Naabu, currently lacks comprehensive unit tests. Adding tests would significantly improve code reliability, ensure safer future modifications, and make the codebase more maintainable.

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Current Status

• The runner.go file handles:
  • Different scan types (SYN, CONNECT, UDP).
  • Complex scan configurations and state management.
  • Various input formats.
  • Output formats (JSON, TXT) and result processing.
• Currently, there is no systematic test coverage for this critical component.

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Proposed Test Coverage

Core Functionality Tests

1. Runner Initialization

   • Test NewRunner with valid and invalid configurations.
   • Verify proper initialization of scanner components (e.g., port scanner, host discovery).
   • Test privilege handling for different scan types (e.g., SYN scans require root privileges).

2. Scan Execution

   • Test RunEnumeration with different scan types (SYN, CONNECT, UDP).
   • Verify proper handling of context cancellation and timeouts.
   • Test warm-up time behavior and rate-limiting functionality.

3. Result Handling

   • Test callback mechanisms (OnResult, OnReceive).
   • Verify proper result collection, deduplication, and output formatting (JSON, CSV, TXT).
   • Test edge cases like empty results or invalid inputs.

4. Error Handling

   • Test behavior with invalid configurations (e.g., missing hosts, invalid ports).
   • Test error handling for network issues (e.g., unreachable hosts, packet drops).
   • Test resume functionality and proper cleanup in Close().

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Example Test Plan (Tabular Format)

Test Case	Input	Expected Behavior	Notes
Runner Initialization
Valid configuration	Options{Host: "example.com", Ports: "80,443"}	Runner initializes successfully with correct scan type and ports.
Invalid configuration	Options{Host: "", Ports: ""}	Returns an error indicating missing required fields.
Privilege check (SYN scan)	Options{ScanType: "s"}	Returns an error if not run as root.	SYN scans require root privileges.
Scan Execution
Basic SYN scan	Options{Host: "example.com", Ports: "80", ScanType: "s"}	Correctly identifies open ports on the target host.
Basic CONNECT scan	Options{Host: "example.com", Ports: "80", ScanType: "c"}	Correctly identifies open ports on the target host.
Context cancellation	Options{Host: "example.com", Ports: "80"} with canceled context	Stops the scan gracefully and returns an error.
Rate limiting	Options{Host: "example.com", Ports: "80", Rate: 100}	Ensures the scan does not exceed the specified rate (100 packets per second).
Result Handling
Callback mechanism	Options{Host: "example.com", Ports: "80", OnResult: callbackFunc}	Invokes the callback function for each result.
Output formats	Options{Host: "example.com", Ports: "80", Output: "output.json"}	Writes results in the specified format (JSON).
Deduplication	Options{Host: "example.com", Ports: "80,80"}	Ensures duplicate ports are not reported multiple times.
Error Handling
Invalid host	Options{Host: "invalid.host", Ports: "80"}	Returns an error indicating the host is unreachable.
Invalid port	Options{Host: "example.com", Ports: "99999"}	Returns an error indicating the port is invalid.
Network issues	Options{Host: "example.com", Ports: "80"} with simulated packet drops	Handles network issues gracefully and retries as per configuration.
Resume functionality	Options{Resume: true} with a partially completed scan	Resumes the scan from the last checkpoint.	Requires a valid resume.cfg file.
Cleanup	Options{Host: "example.com", Ports: "80"}	Ensures all resources are released after Close() is called.

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Benefits of Adding Tests

1. Improved Code Reliability: Ensures the core functionality works as expected.
2. Easier Refactoring: Provides a safety net for future changes.
3. Better Documentation: Tests serve as examples of how the code is intended to be used.
4. Regression Prevention: Catches bugs introduced during development.
5. Easier Onboarding: Helps new contributors understand the codebase.
6. Debugging: Makes it easier to identify and fix issues.

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Next Steps

1. Feedback: I would appreciate feedback on the scope and approach before proceeding with implementation.
2. Implementation: Once approved, I will start writing the tests and submit a PR.

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[ehsandeep]

@knakul853 Sounds good to me! If you’re open to it, feel free to take this on. Thank you!

[knakul853]

please review #1396