patch

Documentation

Overview

The patch package is used to represent information about differences between Roblox Lua API structures.

Similar to the rbxapi package, this package provides a common interface, which is to be implemented elsewhere.

The subpackages rbxapi/diff and rbxapijson/diff provide implementations of this interface.

Index

• type Action
• type Class
• type Differ
• type Enum
• type EnumItem
• type Member
• type Patcher
• type Type
  • func (t Type) String() string

Types

type Action

type Action interface {
	// GetType returns the type of action.
	GetType() Type
	// GetField returns the name of the field being changed, when the action
	// is a Change type. Must return an empty string otherwise.
	GetField() string
	// GetPrev returns the old value of the field being changed, when the
	// action is a Change type. Must return nil otherwise.
	GetPrev() interface{}
	// GetNext returns the new value of the field being changed, when the
	// action is a Change type. Must return nil otherwise.
	GetNext() interface{}
	// String returns a string representation of the action, which is
	// implementation-dependent.
	String() string
}

Action represents a single unit of difference between one API structure and another.

type Class

type Class interface {
	// GetClass returns the class associated with the action. When adding or
	// removing, this is the class being added or removed. When changing, the
	// class is meant to be used only for context.
	GetClass() rbxapi.Class
	Action
}

Class represents an Action that applies to a rbxapi.Class.

type Differ

type Differ interface {
	Diff() []Action
}

Differ is implemented by any value that has a Diff method, which returns the differences between two structures as a list of Actions.

Returned actions may point to values within either structure. As such, these actions should be considered invalid when either structure changes.

type Enum

type Enum interface {
	// GetEnum returns the enum associated with the action. When adding or
	// removing, this is the enum being added or removed. When changing, the
	// enum is meant to be used only for context.
	GetEnum() rbxapi.Enum
	Action
}

Enum represents an Action that applies to a rbxapi.Enum.

type EnumItem

type EnumItem interface {
	// GetEnum returns the enum associated with the action. The enum is meant
	// to be used only for context.
	GetEnum() rbxapi.Enum
	// GetEnumItem returns the enum item associated with the action. When
	// adding or removing, this is the item being added or removed. When
	// changing, the item is meant to be used only for context.
	GetEnumItem() rbxapi.EnumItem
	Action
}

EnumItem represents an Action that applies to a rbxapi.EnumItem.

type Member

type Member interface {
	// GetClass returns the class associated with the action. The class is
	// meant to be used only for context.
	GetClass() rbxapi.Class
	// GetMember returns the member associated with the action. When adding or
	// removing, this is the member being added or removed. When changing, the
	// member is meant to be used only for context.
	GetMember() rbxapi.Member
	Action
}

Member represents an Action that applies to a rbxapi.Member.

type Patcher

type Patcher interface {
	Patch([]Action)
}

Patcher is implemented by any value that has a Patch method, which applies a given list of Actions to a structure. Actions with information that is irrelevant, incomplete, or invalid can be ignored.

Ideally, when the API's "origin" and "target" are compared with a Differ, and the returned list of Actions are passed to a Patcher, the end result is that origin is transformed to match target exactly. This should be the case when origin and target come from the same implementation. In practice, origin and target may have different underlying implementations, in which case it may not be possible for all information to transferred from one to the other.

Implementations must ensure that referred information is properly copied, so that values are not shared between structures.

type Type

type Type int

Type indicates the kind of transformation performed by an Action.

const (
	Remove Type = -1 // The action removes data.
	Change Type = 0  // The action changes data.
	Add    Type = 1  // The action adds data.
)

func (Type) String

func (t Type) String() string

String returns a string representation of the action type.