Config

Complete reference for export_vars, datatable_parameters, and allow_dynamic_parameters

Custom instructions extend the base three-field structure with three OPTIONAL fields, giving the Linter a complete input/output contract.

Instruction Object (Complete Fields)

Field	Type	Required	Description
`name`	`string`	REQUIRED	Unique instruction identifier. Used in error messages; must not duplicate within the same `isa.yml`.
`format`	`string (regex)`	REQUIRED	Regex to match a Gherkin Step. Uses `(?P<name>...)` named groups to capture step parameters.
`instruction_type`	`enum`	REQUIRED	For this section, the applicable value is `custom`.
`export_vars`	`map<string, ExportVar>`	OPTIONAL	Variable contract exported after execution. Map key is the variable name pattern (may contain `{{param}}` interpolation).
`datatable_parameters`	`map<string, DatatableParam>`	OPTIONAL	DataTable field schema.
`allow_dynamic_parameters`	`boolean`	OPTIONAL	Defaults to `false`. When `true`, the Linter accepts any header.

allow_dynamic_parameters

Value	Behavior
`false` (default)	Undeclared headers in the DataTable trigger an `error`
`true`	The Linter accepts any header without error

Use case: When the Step Definition accepts arbitrary key-value pairs (e.g., product extension fields), setting this to true avoids updating the schema every time a new field is added.

- name: Product setup
  format: ^"(?P<alias>[^"]+)" is a product "(?P<productCode>[^"]+)", with table:$
  instruction_type: custom
  allow_dynamic_parameters: true    # ← accept any DataTable fields

  datatable_parameters:
    name:
      type: String
      required: true
      description: "Product name (required)"

In this example, name is required while any other fields are accepted.

Corresponding Gherkin usage:

Given "Widget" is a product "WIDGET_01", with table:
  | name   | color | weight |
  | Widget | red   | 150    |

# Linter validation:
#   ✓ name is a declared required field
#   ✓ color, weight are undeclared, but allow_dynamic_parameters: true → no error

export_vars (Output Layer)

Declares which $var this instruction exports after execution, available for subsequent steps to reference.

ExportVar Object

Field	Type	Required	Description
`type`	`string`	REQUIRED	Variable type. Allowed values: `String`, `Boolean`, `Number`.
`description`	`string`	REQUIRED	Semantic description of the variable, shown in IDE hover and generated docs.
`example`	`scalar`	OPTIONAL	Example value (number / string / boolean).
`nullable`	`boolean`	OPTIONAL (default `false`)	When `true`, null/empty values are allowed; when `false`, null triggers an `error`.

The Map key of export_vars can use {{param}} syntax to reference named capture groups from the format regex. This allows exported variable names to be dynamically generated based on step parameters.

- name: Admin setup
  format: ^"(?P<alias>[^"]+)" is an admin, with table:$
  instruction_type: custom

  export_vars:
    "{{alias}}.id":             # ← alias comes from (?P<alias>...) in format
      type: Number
      description: "Admin ID"
      example: 1
      nullable: false
    "{{alias}}.account":
      type: String
      description: "Admin login account"
      example: "sam"
      nullable: false

Corresponding Gherkin usage:

Given "SAM" is an admin, with table:
  | role        |
  | SUPER_ADMIN |

# alias captures "SAM", Linter knows this step exports:
#   $SAM.id      → Number
#   $SAM.account → String

When (UID="$SAM.id") perform action, call table:
  | account        |
  | $SAM.account   |

# Linter validation:
#   ✓ $SAM.id exists and type is Number
#   ✓ $SAM.account exists and type is String

Types

Type	Description
`String`	String value
`Number`	Integer or decimal number
`Boolean`	`true` / `false`

datatable_parameters (Input Layer)

Declares which fields the instruction's DataTable accepts, enabling the Linter to validate header spelling, types, and required fields at lint-time.

DatatableParam Object

Field	Type	Required	Description
`type`	`string`	REQUIRED	Field type. Allowed values: `String`, `Number`, `Boolean`, `Time`.
`description`	`string`	REQUIRED	Semantic description of the field, shown in IDE hover and generated docs.
`required`	`boolean`	OPTIONAL (default `false`)	When `true`, a missing field in the DataTable triggers an `error`.
`enums`	`array<scalar>`	OPTIONAL	Enumeration constraint; values not in the list trigger an `error`.

Types

Type	Accepted Values
`String`	Any string
`Number`	Integers and decimal numbers
`Boolean`	`true` / `false`
`Time`	`@time`, `@date`, `@localTime` time expressions

Example

- name: Admin setup
  format: ^"(?P<alias>[^"]+)" is an admin, with table:$
  instruction_type: custom

  datatable_parameters:
    role:
      type: String
      required: true
      description: "Admin role"
      enums: ["SUPER_ADMIN", "EDITOR", "VIEWER"]
    department:
      type: String
      required: false
      description: "Department"

Corresponding Gherkin usage:

Given "SAM" is an admin, with table:
  | role        | department |
  | SUPER_ADMIN | Operations |

# Linter validation:
#   ✓ role is required and "SUPER_ADMIN" is in enums
#   ✓ department is a declared optional field
#   ✗ If written as "deparment" (missing a t) → error: undeclared field
#   ✗ If role value is "ADMIN" → error: not in enums
#   ✗ If role is omitted → error: required field missing

Complete Example

- name: Admin setup
  format: ^"(?P<alias>[^"]+)" is an admin, with table:$
  instruction_type: custom

  export_vars:
    "{{alias}}.id":
      type: Number
      description: "Admin ID"
      example: 1
      nullable: false
    "{{alias}}.account":
      type: String
      description: "Admin login account"
      example: "sam"
      nullable: false

  datatable_parameters:
    role:
      type: String
      required: true
      description: "Admin role"
      enums: ["SUPER_ADMIN", "EDITOR", "VIEWER"]
    department:
      type: String
      required: false
      description: "Department"

Config

Instruction Object (Complete Fields)

allow_dynamic_parameters

export_vars (Output Layer)

ExportVar Object

`{{param}}` Interpolation

Types

datatable_parameters (Input Layer)

DatatableParam Object

Types

Example

Complete Example

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