Builder package for tests

This package holds Builder functions that can be used to create struct in tests with less noise.

One of the most important characteristic of a unit test (and any type of test really) is readability. This means it should be easy to read but most importantly it should clearly show the intent of the test. The setup (and cleanup) of the tests should be as small as possible to avoid the noise. Those builders exists to help with that.

There is two types of functions defined in that package :

* *Builders*: create and return a struct
* *Modifiers*: return a function
  that will operate on a given struct. They can be applied to other
  Modifiers or Builders.

Most of the Builder (and Modifier) that accepts Modifiers defines a type (TypeOp) that can be satisfied by existing function in this package, from other package or inline. An example would be the following.

    // Definition
    type TaskRunOp func(*v1alpha1.TaskRun)
    func TaskRun(name, namespace string, ops ...TaskRunOp) *v1alpha1.TaskRun {
        // […]
    }
    func TaskRunOwnerReference(kind, name string) TaskRunOp {
        return func(t *v1alpha1.TaskRun) {
            // […]
        }
    }
    // Usage
    t := TaskRun("foo", "bar", func(t *v1alpha1.TaskRun){
        // Do something with the Task struct
        // […]
    })

The main reason to define the Op type, and using it in the methods signatures is to group Modifier function together. It makes it easier to see what is a Modifier (or Builder) and on what it operates.

By convention, this package is import with the "tb" as alias. The examples make that assumption.

Example

Let's look at a non-exhaustive example.

package builder_test

import (
    "fmt"
    "testing"

    "github.com/tektoncd/pipeline/pkg/apis/pipeline/v1alpha1"
    tb "github.com/tektoncd/pipeline/test/builder"
    corev1 "k8s.io/api/core/v1"
)

func MyTest(t *testing.T) {
    // You can declare re-usable modifiers
    myStep := tb.Step("my-step", "myimage")
    // … and use them in a Task definition
    myTask := tb.Task("my-task", "namespace", tb.TaskSpec(
        tb.Step("simple-step", "myotherimage", tb.Command("/mycmd")),
        myStep,
    ))
    // … and another one.
    myOtherTask := tb.Task("my-other-task", "namespace",
        tb.TaskSpec(myStep,
            tb.TaskInputs(tb.InputsResource("workspace", v1alpha1.PipelineResourceTypeGit)),
        ),
    )
    myClusterTask := tb.ClusterTask("my-task", tb.ClusterTaskSpec(
        tb.Step("simple-step", "myotherimage", tb.Command("/mycmd")),
    ))
    // A simple definition, with a Task reference
    myTaskRun := tb.TaskRun("my-taskrun", "namespace", tb.TaskRunSpec(
        tb.TaskRunTaskRef("my-task"),
    ))
    // … or a more complex one with inline TaskSpec
    myTaskRunWithSpec := tb.TaskRun("my-taskrun-with-spec", "namespace", tb.TaskRunSpec(
        tb.TaskRunInputs(
            tb.TaskRunInputsParam("myarg", "foo"),
            tb.TaskRunInputsResource("workspace", tb.TaskResourceBindingRef("git-resource")),
        ),
        tb.TaskRunTaskSpec(
            tb.TaskInputs(
                tb.InputsResource("workspace", v1alpha1.PipelineResourceTypeGit),
                tb.InputsParam("myarg", tb.ParamDefault("mydefault")),
            ),
            tb.Step("mycontainer", "myimage", tb.Command("/mycmd"),
                tb.Args("--my-arg=$(inputs.params.myarg)"),
            ),
        ),
    ))
    // Pipeline
    pipeline := tb.Pipeline("tomatoes", "namespace",
        tb.PipelineSpec(tb.PipelineTask("foo", "banana")),
    )
    // … and PipelineRun
    pipelineRun := tb.PipelineRun("pear", "namespace",
        tb.PipelineRunSpec("tomatoes", tb.PipelineRunServiceAccount("inexistent")),
    )
    // And do something with them
    // […]
    if _, err := c.PipelineClient.Create(pipeline); err != nil {
        t.Fatalf("Failed to create Pipeline `%s`: %s", "tomatoes", err)
    }
    if _, err := c.PipelineRunClient.Create(pipelineRun); err != nil {
        t.Fatalf("Failed to create PipelineRun `%s`: %s", "pear", err)
    }
    // […]
}