Common Mistakes

Multi Line Expressions in if

Wrong

if: |
  ${{
    success()
    && needs.test.result == 'success'
  }}

this ends up like "${{ format('{0}\n', success() && needs.test.result == 'success') }}" and is equivalent to "always()"

Correct

if: |-
  ${{
    success()
    && needs.test.result == 'success'
  }}

if: |
  success()
  && needs.test.result == 'success'

if: |-
  success()
  && needs.test.result == 'success'

Multi Line Expressions with non string type

Wrong

matrix: |
  ${{
    fromjson('{
        "Hello": ["World"]
    }')
  }}

this ends up like "${{ format('{0}\n', fromjson('{\n "Hello": ["World"]\n }')) }}" and is equivalent to "Object\n"

Correct

matrix: |-
  ${{
    fromjson('{
        "Hello": ["World"]
    }')
  }}

Passing parameter as boolean in Reusable Workflows

Wrong for push

on:
  push:
  workflow_dispatch:
    inputs:
      BOOLEAN:
        type: boolean
jobs:
  test:
    uses: ./.github/workflows/workflow.yml
    with:
      BOOLEAN: ${{ inputs.BOOLEAN }}

Correct

on:
  push:
  workflow_dispatch:
    inputs:
      BOOLEAN:
        type: boolean
jobs:
  test:
    uses: ./.github/workflows/workflow.yml
    with:
      BOOLEAN: ${{ inputs.BOOLEAN || false }}

Passing string as number in Reusable Workflows

Wrong

on:
  push:
  workflow_dispatch:
    inputs:
      NUMBER: {}
jobs:
  test:
    uses: ./.github/workflows/workflow.yml
    with:
      NUMBER: ${{ inputs.NUMBER }}

Wrong for push

on:
  push:
  workflow_dispatch:
    inputs:
      NUMBER: {}
jobs:
  test:
    uses: ./.github/workflows/workflow.yml
    with:
      NUMBER: ${{ fromJson(inputs.NUMBER) }}

Correct

on:
  push:
  workflow_dispatch:
    inputs:
      NUMBER: {}
jobs:
  test:
    uses: ./.github/workflows/workflow.yml
    with:
      NUMBER: ${{ fromJson(inputs.NUMBER || '0') }}

on:
  push:
  workflow_dispatch:
    inputs:
      NUMBER: {}
jobs:
  test:
    uses: ./.github/workflows/workflow.yml
    with:
      NUMBER: ${{ inputs.NUMBER && fromJson(inputs.NUMBER) || 0 }}

Accessing index by actions context in if

Wrong

if: steps[${{ steps.token.outputs.y }}].outputs.test == 'ok'

This ends up as ${{ success() && format('steps[{0}].outputs.test == ''ok''', steps.token.outputs.y) }} and is similar to ${{ success() }} or ${{ success() && 'Non Empty String' }}.

Correct

if: steps[steps.token.outputs.y].outputs.test == 'ok'