azure-pipelines - 多次访问输出变量会呈现空字符串

Question

我正在尝试从多个连续阶段的一个阶段访问输出变量。

第一次访问变量时，我可以访问该值，但下次我尝试它是一个空字符串。

在下面的示例中B1打印'production'但C1打印''

trigger:
  - yaml-testing

pool:
  vmImage: windows-2019

stages:
- stage: A
  jobs:
  - job: A1
    steps:
      - task:  InlinePowershell@1
        name: setvar
        inputs:
          Script: |
            Write-Host "##vso[task.setvariable variable=Environment;isOutput=true]production"

- stage: B
  dependsOn: A
  variables:
    Environment: $[ stageDependencies.A.A1.outputs['setvar.Environment'] ]
  jobs:
  - job: B1
    steps:
      - task:  InlinePowershell@1
        name: printvar1
        inputs:
          Script: |
            Write-Host 'B1' 
            Write-Host $(Environment)

- stage: C
  dependsOn: B
  variables:
    Environment: $[ stageDependencies.A.A1.outputs['setvar.Environment'] ]
  jobs:
  - job: C1
    steps:
      - task:  InlinePowershell@1
        name: printvar2
        inputs:
          Script: |
            Write-Host 'C1' 
            Write-Host $(Environment)   

日志如下所示：

// Stage: B
Job preparation parameters
Variables:
  Environment:
    Parsing expression: <stageDependencies.A.A1.outputs['setvar.Environment']>
    Evaluating: stageDependencies['A']['A1']['outputs']['setvar.Environment']
    Result: 'production'

// Stage: C
Job preparation parameters
Variables:
  Environment:
    Parsing expression: <stageDependencies.A.A1.outputs['setvar.Environment']>
    Evaluating: stageDependencies['A']['A1']['outputs']['setvar.Environment']
    Expanded: Null
    Result: ''