array-default.yaml

apiVersion: tekton.dev/v1beta1
kind: TaskRun
metadata:
  generateName: array-with-default-
spec:
  params:
    - name: array-to-echo
      value:
        - "foo"
        - "bar"
  taskSpec:
    params:
      - name: array-to-echo
        type: array
      - name: another-array-to-echo
        type: array
        default:
        - "foo-default"
        - "bar-default"
      - name: string-to-echo
        type: string
        default: "baz"
    steps:
      # this step should echo "foo bar foo-default bar-default baz"
      - name: echo-params
        image: bash:3.2
        args: [
          "$(params.array-to-echo[*])",
          "$(params.another-array-to-echo[*])",
          "$(params.string-to-echo)",
        ]
        script: |
          #!/usr/bin/env bash
          if [[ $# != 5 ]]; then
            echo "failed to validate the length of the arguments"
            echo "Want: 5, Got: $#"
            exit 1
          fi
          if [[ $1 != "foo" ]]; then
            echo "failed to validate the first argument to the script"
            echo "Want: foo, Got: $1"
            exit 1
          fi
          if [[ $2 != "bar" ]]; then
            echo "failed to validate the second argument to the script"
            echo "Want: bar, Got: $2"
            exit 1
          fi
          if [[ $3 != "foo-default" ]]; then
            echo "failed to validate the third argument to the script"
            echo "Want: foo-default, Got: $3"
            exit 1
          fi
          if [[ $4 != "bar-default" ]]; then
            echo "failed to validate the fourth argument to the script"
            echo "Want: bar-default, Got: $4"
            exit 1
          fi
          if [[ $5 != "baz" ]]; then
            echo "failed to validate the fifth argument to the script"
            echo "Want: baz, Got: $5"
            exit 1
          fi