Documentation ¶
Overview ¶
Package compare has utilities for comparing values. The DeepEquals and Diff functions are the main entry points.
Index ¶
- Constants
- Variables
- func Compare(reference, value interface{}, handler Handler)
- func DeepEqual(reference, value interface{}) bool
- func IsNil(o interface{}) bool
- func Register(f interface{})
- type Action
- type Comparator
- type Custom
- type EntryOp
- type Fragment
- type Handler
- type IndexOp
- type LengthOp
- type MemberOp
- type MissingOp
- type NilOp
- type Path
- func (p Path) Diff(reference, value interface{}) Path
- func (p Path) Entry(key, reference, value interface{}) Path
- func (p Path) Format(f fmt.State, r rune)
- func (p Path) Index(i int, reference, value interface{}) Path
- func (p Path) Length(reference, value interface{}) Path
- func (p Path) Member(name string, reference, value interface{}) Path
- func (p Path) Missing(reference, value interface{}) Path
- func (p Path) Nil(reference, value interface{}) Path
- func (p Path) Type(reference, value interface{}) Path
- type TypeOp
Constants ¶
const ( Length = LengthOp("·length") Type = TypeOp("·type") Nil = NilOp("nil") Key = MissingOp("key") )
const (
// Missing is used when values are found to be missing from a container
Missing = invalid("Missing")
)
Variables ¶
var (
// LimitReached the value panic is given to abort a comparison early.
LimitReached = diffLimit{}
)
Functions ¶
func Compare ¶
func Compare(reference, value interface{}, handler Handler)
Compare delivers all the differences it finds to the specified Handler. If the reference and value are equal, the handler will never be invoked.
func DeepEqual ¶
func DeepEqual(reference, value interface{}) bool
DeepEqual compares a value against a reference and returns true if they are equal.
func IsNil ¶
func IsNil(o interface{}) bool
IsNil returns true if o is nil (either directly or a boxed nil).
func Register ¶
func Register(f interface{})
Register assigns the function f with signature func(comparator, T, T) to be used as the default comparator for instances of type T. f may return nothing or a CompareAction. Register will panic if f does not match the expected signature, or if a custom comparator for type T has already been registered.
Types ¶
type Action ¶
type Action int
Action is the optional return value type of functions passes to Register and Custom.Register.
type Comparator ¶
Comparator is passed to custom comparison functions holding the current comparison context.
func (Comparator) AddDiff ¶
func (t Comparator) AddDiff(reference, value interface{})
AddDiff can be used by custom comparison functions to register a new difference. The current handler will be invoked with the current path plus a Diff fragment.
func (Comparator) Compare ¶
func (t Comparator) Compare(reference, value interface{})
Compare can be called by custom comparison functions to recurse into children.
func (Comparator) With ¶
func (t Comparator) With(p Path) Comparator
With returns a new Comparator based on t but with the specified Path.
type Custom ¶
type Custom struct {
// contains filtered or unexported fields
}
Custom is a collection of custom comparators that will be used instead of the default comparison methods when comparing objects of the registered types.
func (*Custom) Compare ¶
Compare delivers all the differences it finds to the specified Handler. Compare uses the list of custom comparison handlers registered with Custom.Register(), falling back to the default comparison method for the type when no custom comparison function has been registered with this custom. If the reference and value are equal, the handler will never be invoked.
func (*Custom) DeepEqual ¶
DeepEqual compares a value against a reference using the custom comparators and returns true if they are equal.
func (*Custom) Diff ¶
Diff returns the differences between the reference and the value. Diff uses the list of custom comparison handlers registered with Custom.Register(), falling back to the default comparison method for the type when no custom comparison function has been registered with this custom. The maximum number of differences is controlled by limit, which must be >0. If they compare equal, the length of the returned slice will be 0.
func (*Custom) Register ¶
func (c *Custom) Register(f interface{})
Register assigns the function f with signature func(comparator, T, T) to be used as the comparator for instances of type T when using Custom.Compare(). f may return nothing or a CompareAction. Register will panic if f does not match the expected signature, or if a comparator for type T has already been registered with this Custom.
type EntryOp ¶
type EntryOp struct {
Key interface{} // The map key
}
EntryOp is the fragment operation type for map entry comparisons.
type Fragment ¶
type Fragment struct { // Operation holds the operation occurring at this level in the path. Operation interface{} // Reference holds the entry in the reference hierarchy to apply the operation to Reference interface{} // Value holds the equivalent entry in the value hierarchy to apply the the operation to Value interface{} }
Fragment is an entry in a Path
type Handler ¶
type Handler func(Path)
Handler is the type for a callback that differences are delivered to. It may panic with LimitReached to abort further difference processing.
type IndexOp ¶
type IndexOp int
IndexOp is the fragment operation type for array / slice index comparisons.
type LengthOp ¶
type LengthOp string
LengthOp is the fragment operation type for array / slice length comparisons.
type MemberOp ¶
type MemberOp string
MemberOp is the fragment operation type for member comparisons.
type MissingOp ¶
type MissingOp string
MissingOp is the fragment operation type for absent entries in arrays, slices and maps.
type Path ¶
type Path []Fragment
Path represents a path from the root of an object hierarchy
func Diff ¶
Diff returns the differences between the reference and the value. The maximum number of differences is controlled by limit, which must be >0. If they compare equal, the length of the returned slice will be 0.