Poindexter/AUDIT-TESTING.md

Test Coverage and Quality Audit

This document provides an audit of the test coverage, quality, and practices for the Poindexter project.

1. Coverage Analysis

Line Coverage

• Overall Coverage: 70.0%
• Coverage with gonum tag: 77.3%

The overall line coverage is reasonably good, but there are significant gaps in certain areas. The gonum build tag increases coverage by enabling the optimized k-d tree backend, but the DNS tools and some parts of the k-d tree implementation remain untested.

Branch Coverage

Go's native tooling focuses on statement coverage and does not provide a direct way to measure branch coverage. While statement coverage is a useful metric, it does not guarantee that all branches of a conditional statement have been tested.

Critical Paths

The critical paths in this project are the k-d tree implementation and the DNS tools. The k-d tree is the core data structure, and its correctness is essential for the project's functionality. The DNS tools are critical for any application that needs to interact with the DNS system. The tests for the k-d tree are more comprehensive than the tests for the DNS tools, which, as noted, have significant gaps.

Untested Code

The following files and functions have low or 0% coverage:

• dns_tools.go: This file has the most significant coverage gaps. The following functions are entirely untested:
  • DNSLookup and DNSLookupWithTimeout
  • DNSLookupAll and DNSLookupAllWithTimeout
  • ReverseDNSLookup
  • RDAPLookupDomain, RDAPLookupDomainWithTimeout
  • RDAPLookupIP, RDAPLookupIPWithTimeout
  • RDAPLookupASN, RDAPLookupASNWithTimeout
• kdtree_gonum_stub.go: The stub functions in this file are untested when the gonum tag is not used.
• kdtree_helpers.go: Some of the helper functions for building k-d trees have low coverage.

2. Test Quality

Test Independence

The tests appear to be independent and do not rely on a specific execution order. There is no evidence of shared mutable state between tests.

Test Clarity

The test names are generally descriptive, and the tests follow the Arrange-Act-Assert pattern. However, the assertions are often simple string comparisons or checks for non-nil values, which could be more robust. The use of a dedicated assertion library (like testify/assert) would improve readability and provide more detailed failure messages.

Test Reliability

The tests are not flaky and do not seem to be time-dependent. External dependencies, such as DNS and RDAP services, are not mocked, which means the tests that rely on them will fail if the services are unavailable.

3. Missing Tests

Security Tests

There are no dedicated security tests in the project. This is a significant gap, as the project deals with network requests and could be vulnerable to attacks such as DNS spoofing or denial-of-service attacks.

Performance Tests

The project includes benchmarks (make bench), but it lacks comprehensive performance tests. Load and stress tests would be beneficial to understand how the system behaves under heavy load and to identify potential bottlenecks.

Edge Cases

• dns_tools.go:
  • Tests for invalid domain names and IP addresses.
  • Tests for timeouts and network errors.
  • Tests for empty DNS responses.
• kdtree_gonum.go:
  • Tests for empty point lists.
  • Tests for k-d trees with duplicate points.
  • Tests for queries with a k value greater than the number of points in the tree.

Error Paths

• The error paths in the DNS and RDAP lookup functions are not tested. This includes handling of network errors, timeouts, and non-existent domains.

Integration Tests

• There are no integration tests to verify the interaction between the k-d tree and the DNS tools.

4. Anti-Patterns

Ignored Tests

There are no ignored tests in the project, which is a positive finding.

Testing Implementation Details

Some tests, particularly in dns_tools_test.go, check the structure of the returned objects rather than their behavior. For example, TestDNSLookupResultStructure checks the number of records in the result, but not the content of the records.

Lack of Mocking

The tests for dns_tools.go make live network calls, which makes them slow and unreliable. Mocking the network requests would make the tests faster and more predictable.

5. Suggested Tests to Add

dns_tools.go

• Add unit tests for all public functions, using a mocked DNS resolver and RDAP client.
• Test for various DNS record types and edge cases (e.g., empty TXT records, CNAME chains).
• Test the error handling for network errors, timeouts, and invalid inputs.
• Add tests for the RDAP lookup functions, covering different response types and error conditions.

kdtree_gonum.go

• Add tests for edge cases, such as empty point lists and k values greater than the number of points.
• Add tests for different distance metrics (Manhattan, Chebyshev).
• Add tests for high-dimensional data.

Integration Tests

• Add integration tests that use the dns_tools.go to look up IP addresses and then use the k-d tree to find the nearest neighbors.

Security Tests

• Add tests for DNS spoofing vulnerabilities.
• Add tests for denial-of-service attacks.

Performance Tests

• Add load tests to simulate a high volume of DNS and k-d tree queries.
• Add stress tests to identify the breaking points of the system.

By addressing the issues outlined in this audit, the Poindexter project can significantly improve its test coverage, quality, and reliability.