setup:
  - do:
      indices.create:
        index: test_index
        body:
          settings:
            number_of_shards: "1"
            number_of_replicas: "0"

  - do:
      cluster.health:
        wait_for_status: green

---
"Explain API with empty command list":

  - do:
      cluster.reroute:
        explain: true
        dry_run: true
        body:
          commands: []

  - match: {explanations: []}

---
"Explain API for non-existant node & shard":

  - do:
      cluster.reroute:
        explain: true
        dry_run: true
        body:
          commands:
            - cancel:
                index: test_index
                shard: 9
                node: node_0

  - match: {explanations.0.command: cancel}
  - match:
      explanations.0.parameters:
        index: test_index
        shard: 9
        node: node_0
        allow_primary: false
  - match: {explanations.0.decisions.0.decider: cancel_allocation_command}
  - match: {explanations.0.decisions.0.decision: "NO"}
  - is_true: explanations.0.decisions.0.explanation