🧪 Add tests for UnmarshalCertificate in internal/identity

[filmil]

🎯 What: The testing gap addressed is the lack of tests for UnmarshalCertificate in internal/identity/identity.go.

📊 Coverage: The new test suite in internal/identity/identity_test.go covers:

• Success: Successful round-trip of a generated certificate using MarshalCertificate and UnmarshalCertificate.
• Invalid PEM: Error handling for input that is not valid PEM data.
• Empty Input: Error handling for empty byte slices.
• Wrong PEM Type: Verification that unmarshaling fails when provided with a valid PEM block of a non-certificate type (which results in invalid DER for certificate parsing).
• Invalid DER: Error handling for valid "CERTIFICATE" PEM blocks containing corrupted DER data.

✨ Result: Increased reliability and coverage of the identity package, ensuring certificate importing behaves correctly under various conditions.

This pull request has been created by an automated coding assistant,
with human supervision.

Full prompt:

🧪 Testing Improvement Task

You are a testing-focused agent. Your mission is to analyze and implement a testing improvement that will increase the reliability and coverage of the codebase.

Task Details

File: internal/identity/identity.go:171
Issue: Missing test for UnmarshalCertificate in internal/identity/identity.go

Language: go

Current Code:

func MarshalCertificate(cert *x509.Certificate) []byte {
	return pem.EncodeToMemory(&pem.Block{Type: "CERTIFICATE", Bytes: cert.Raw})
}

// UnmarshalCertificate imports a certificate from PEM format.
func UnmarshalCertificate(data []byte) (*x509.Certificate, error) {
	block, _ := pem.Decode(data)
	if block == nil {
		return nil, fmt.Errorf("failed to decode PEM block")
	}
	return x509.ParseCertificate(block.Bytes)
}

// SignMessage signs a protobuf message. It clears the 'auth' field before signing.
func (i *Identity) SignMessage(msg proto.Message) (signature []byte, certificate []byte, err error) {

Rationale: Function UnmarshalCertificate seems straightforward to test.

Your Process

1. 🔍 UNDERSTAND - Analyze the Testing Gap

• Review the code that needs testing
• Understand what functionality should be tested
• Identify edge cases and error conditions

2. 📋 PLAN - Design the Test Strategy

Before writing tests, plan your approach:

• What test framework is used in this project?
• What existing test patterns should you follow?
• What scenarios need to be covered?

3. 🔧 IMPLEMENT - Write Effective Tests

• Write clear, focused test cases
• Follow existing testing patterns and conventions
• Cover happy paths, edge cases, and error conditions
• Use appropriate mocks and test doubles
• Ensure tests are deterministic and not flaky

4. ✅ VERIFY - Validate the Tests

• Run the new tests to ensure they pass
• Run the full test suite to ensure no regressions
• Verify the tests actually catch bugs (try breaking the code to confirm the test fails)

5. 📝 DOCUMENT - Explain the Testing Improvement

Create a PR with:

• Title: "🧪 [testing improvement description]"
• Description with:
  • 🎯 What: The testing gap addressed
  • 📊 Coverage: What scenarios are now tested
  • ✨ Result: The improvement in test coverage

Remember: Good tests are the safety net that allows confident refactoring. Write tests that catch real bugs.

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PR created automatically by Jules for task 8763075454524245418 started by @filmil

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