distinguish task dependencies: ordering vs resource

[jerop]

Changes

there are two types of dependencies between tasks:

• resource-dependency: based on resources needed from parent task,
  which includes results, workspaces and resources
• ordering-dependency: based on runAfter which provides sequencing of
  tasks when there may not be resource dependencies

however, it is currently difficult to distinguish between the two

this PR provides a way to know the dependency type and will be useful
for future work such as allowing execution of ordering-dependent tasks
when continueAfterSkip is set to true

/kind misc

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Release Notes

NONE

[tekton-robot]

The following is the coverage report on the affected files.
Say /test pull-tekton-pipeline-go-coverage to re-run this coverage report

File	Old Coverage	New Coverage	Delta
pkg/apis/pipeline/v1alpha1/pipeline_types.go	69.0%	73.8%	4.8

[ghost]

This looks good to me. I do wonder if these need to be public funcs though? If we keep them private I think we still get the benefit of their naming to help distinguish purpose but we can also consider them an "implementation detail" of Deps() and avoid testing them right now. What do you think?

[tekton-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: sbwsg

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[tekton-robot]

The following is the coverage report on the affected files.
Say /test pull-tekton-pipeline-go-coverage to re-run this coverage report

File	Old Coverage	New Coverage	Delta
pkg/apis/pipeline/v1beta1/pipeline_types.go	63.9%	69.4%	5.5

[tekton-robot]

The following is the coverage report on the affected files.
Say /test pull-tekton-pipeline-go-coverage to re-run this coverage report

File	Old Coverage	New Coverage	Delta
pkg/apis/pipeline/v1beta1/pipeline_types.go	63.9%	69.4%	5.5

[jerop]

This looks good to me. I do wonder if these need to be public funcs though? If we keep them private I think we still get the benefit of their naming to help distinguish purpose but we can also consider them an "implementation detail" of Deps() and avoid testing them right now. What do you think?

agreed, made them private -- thanks!

[jerop]

/test pull-tekton-pipeline-integration-tests

[pritidesai]

/lgtm