Go Testing and Debugging

Writing Unit Tests

Motivation: Unit tests are crucial for ensuring the correctness and robustness of the codebase. They help verify individual components and functions in isolation, promoting code quality and reducing the risk of introducing regressions.

Structure: The Go testing framework is built into the language. Tests are typically placed in files named _test.go within the same package as the code being tested.

Example:

package helpers
          
          import (
              "testing"
          )
          
          func TestGetCredentials(t *testing.T) {
              // Arrange: Set up test data and environment
              // Act: Execute the function under test
              // Assert: Verify expected outcomes
          }
          

Reference:

https://golang.org/pkg/testing/

Debugging Techniques

Motivation: Debugging tools are essential for identifying and resolving issues during development. They provide a way to inspect code execution, analyze variables, and pinpoint the root cause of errors.

Options:

• go test -v: Enables verbose output, providing detailed information about test execution, including pass/fail status and output from test functions.

• go test -run: Runs specific tests based on a regular expression. This allows for focusing on specific areas of the code.

• go test -cover: Enables code coverage analysis, highlighting which lines of code are executed by tests.

• go test -coverprofile: Generates a coverage profile file that can be used to visualize code coverage using tools like go tool cover.

• go run: Executes a Go program directly, allowing for interactive debugging.

• go build -gcflags=-N -l: Disables optimization and inlining, allowing for easier debugging of compiled code.

• dlv debug: A powerful debugger that provides features like breakpoints, step-by-step execution, and variable inspection.

Example:

# Run all tests with verbose output
          go test -v
          
          # Run tests matching "GetCredentials"
          go test -run GetCredentials
          
          # Generate a coverage profile
          go test -coverprofile=coverage.out
          
          # Use `go tool cover` to visualize coverage
          go tool cover -html=coverage.out
          

Reference:

https://golang.org/doc/go1.10/testing/

https://github.com/go-delve/delve

Using docker-credential-helpers for Testing

Motivation: For testing scenarios involving Docker credentials, it’s crucial to ensure that the credential helpers are correctly configured and functioning as expected.

Example:

// Create a test helper to mock credential storage
          type MockCredentialHelper struct {
              // ... (Mock implementation of helper methods)
          }
          
          // Use the mock helper during tests to control the credential storage behavior
          func TestWithMockHelper(t *testing.T) {
              // ...
          }
          

Reference:

https://github.com/docker/docker-credential-helpers

Note: The docker-credential-helpers project includes dedicated tests for various credential helper implementations. You can refer to the existing tests for guidance on writing tests for specific helpers.