environment vars

    scopes:
    - name: global
      dvars:
      - name: student_name
        value: '{{ env "STUDENT_NAME" |default "Tom Hanks" }}'
      - name: student_age
        value: '{{ env "STUDENT_AGE" |default 28 }}'
    dvars:
    - name: cli
      value: |
        echo """
        student details:
        name: {{.student_name}}
        age: {{.student_age}}
        """
    tasks:
    - name: task
      task:
      - func: shell
        desc: this show an example of the empty value is mapped to None
        vars:
          person: ""
        dvars:
        - name: someone
          value: '{{ .person }}'
        - name: i_am_empty
          value: '{{ "" }}'
        - name: empty_env_var
          value: '{{ env "EMPTY_VAR" }}'
        do: |
          echo "{{.someone}}"
          echo "{{.i_am_empty}}"
          echo "{{.empty_env_var}}"
      - func: cmd
        do:
        - name: inspect
          cmd:
          - exec_vars
          - exec_base_vars
    

    loading [Config]:  ./tests/functests/upconfig.yml
    Main config:
                 Version -> 1.0.0
                  RefDir -> ./tests/functests
                 WorkDir -> cwd
              AbsWorkDir -> /up_project/up
                TaskFile -> c0046
                 Verbose -> vvv
              ModuleName -> self
               ShellType -> /bin/sh
           MaxCallLayers -> 8
                 Timeout -> 3600000
     MaxModuelCallLayers -> 256
               EntryTask -> task
      ModRepoUsernameRef -> 
      ModRepoPasswordRef -> 
    work dir: /up_project/up
    -exec task: task
    loading [Task]:  ./tests/functests/c0046
    module: [self], instance id: [dev], exec profile: []
    profile -  envVars:
    
    (*core.Cache)({
    })
    
    Task1: [task ==> task:  ]
    -Step1: [: this show an example of the empty value is mapped to None ]
    self: final context exec vars:
    
    (*core.Cache)({
      "someone": "None",
      "student_name": "Tom Hanks",
      "student_age": "28",
      "cli": "echo \"\"\"\nstudent details:\nname: Tom Hanks\nage: 28\n\"\"\"\n",
      "up_runtime_task_layer_number": 0,
      "person": "",
      "i_am_empty": "None",
      "empty_env_var": "None"
    })
    
    cmd( 1):
    echo "{{.someone}}"
    echo "{{.i_am_empty}}"
    echo "{{.empty_env_var}}"
    
    
    -
    None
    None
    None
    
    -
     .. ok
    . ok
    -Step2:
    self: final context exec vars:
    
    (*core.Cache)({
      "student_name": "Tom Hanks",
      "student_age": "28",
      "cli": "echo \"\"\"\nstudent details:\nname: Tom Hanks\nage: 28\n\"\"\"\n",
      "last_result": (*utils.ExecResult)({
        Cmd: "echo \"None\"\necho \"None\"\necho \"None\"\n",
        Code: 0,
        Output: "None\nNone\nNone",
        ErrMsg: ""
      }),
      "up_runtime_task_layer_number": 0
    })
    
    ~SubStep1: [inspect:  ]
     1: inspect[exec_vars]
    (*core.Cache)({
      "up_runtime_task_layer_number": 0,
      "student_name": "Tom Hanks",
      "student_age": "28",
      "cli": "echo \"\"\"\nstudent details:\nname: Tom Hanks\nage: 28\n\"\"\"\n",
      "last_result": (*utils.ExecResult)({
        Cmd: "echo \"None\"\necho \"None\"\necho \"None\"\n",
        Code: 0,
        Output: "None\nNone\nNone",
        ErrMsg: ""
      })
    })
    
     2: inspect[exec_base_vars]
    {
      "student_name": "Tom Hanks",
      "student_age": "28",
      "cli": "echo \"\"\"\nstudent details:\nname: Tom Hanks\nage: 28\n\"\"\"\n",
      "last_result": (*utils.ExecResult)({
        Cmd: "echo \"None\"\necho \"None\"\necho \"None\"\n",
        Code: 0,
        Output: "None\nNone\nNone",
        ErrMsg: ""
      })
    }