mcp-vosdroits testing.instructions.md

Testing Standards

General Principles

• Write tests for all public functions and methods
• Test both success and error paths
• Use table-driven tests for multiple scenarios
• Keep tests simple and focused
• Tests should be fast and deterministic
• Avoid testing implementation details

Go Testing Patterns

Table-Driven Tests

Use table-driven tests to test multiple scenarios efficiently:

func TestFunction(t *testing.T) {
    tests := []struct {
        name    string
        input   InputType
        want    OutputType
        wantErr bool
    }{
        // test cases
    }
    
    for _, tt := range tests {
        t.Run(tt.name, func(t *testing.T) {
            // test logic
        })
    }
}

Subtests

Use t.Run to organize related tests and enable selective test execution.

Test Helpers

• Mark helper functions with t.Helper()
• Use t.Cleanup() for resource cleanup
• Create test fixtures for complex setup

MCP Server Testing

Testing Tool Handlers

• Test with valid and invalid inputs
• Verify JSON schema validation
• Test context cancellation
• Mock external dependencies
• Verify error messages are informative

Testing Resources

• Test resource read operations
• Verify MIME types and content
• Test resource not found scenarios

Testing Prompts

• Test prompt generation with various arguments
• Verify prompt message formatting

Mocking

• Use interfaces for dependencies
• Create mock implementations for testing
• Consider using testify/mock for complex mocks
• Keep mocks simple and focused

Coverage

• Aim for high test coverage but prioritize meaningful tests
• Use go test -cover to check coverage
• Focus on testing critical paths and edge cases

Best Practices

• Name tests descriptively: Test_FunctionName_Scenario
• Don't test the Go standard library
• Avoid sleeps in tests; use channels or mocks
• Run tests with race detector: go test -race
• Keep tests isolated and independent