reflect/protoreflect: add Value.Equal method
The Value.Equal method compares Values in a way that is
analogous to the reflect.DeepEqual function.
Most of the implementation is moved from the "proto" package,
with proto.Equal implemented in terms of protoreflect.Value.Equal.
Change-Id: Ie9d5f6c073dc49fa59f78385c441db8137de5ec5
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/450775
TryBot-Bypass: Heschi Kreinick <heschi@google.com>
Reviewed-by: Damien Neil <dneil@google.com>
Reviewed-by: Oleksii Prokopchuk <prokopchuk@google.com>
Reviewed-by: Christian Höppner <hoeppi@google.com>
Run-TryBot: Lasse Folger <lassefolger@google.com>
diff --git a/proto/equal.go b/proto/equal.go
index 67948dd..baa1bc1 100644
--- a/proto/equal.go
+++ b/proto/equal.go
@@ -5,30 +5,34 @@
package proto
import (
- "bytes"
- "math"
"reflect"
- "google.golang.org/protobuf/encoding/protowire"
"google.golang.org/protobuf/reflect/protoreflect"
)
-// Equal reports whether two messages are equal.
+// Equal reports whether two messages are equal,
+// by recursively comparing the fields of the message.
+//
+// - Bytes fields are equal if they contain identical bytes.
+// Empty bytes (regardless of nil-ness) are considered equal.
+//
+// - Floating-point fields are equal if they contain the same value.
+// Unlike the == operator, a NaN is equal to another NaN.
+//
+// - Other scalar fields are equal if they contain the same value.
+//
+// - Message fields are equal if they have
+// the same set of populated known and extension field values, and
+// the same set of unknown fields values.
+//
+// - Lists are equal if they are the same length and
+// each corresponding element is equal.
+//
+// - Maps are equal if they have the same set of keys and
+// the corresponding value for each key is equal.
+//
// If two messages marshal to the same bytes under deterministic serialization,
// then Equal is guaranteed to report true.
-//
-// Two messages are equal if they belong to the same message descriptor,
-// have the same set of populated known and extension field values,
-// and the same set of unknown fields values. If either of the top-level
-// messages are invalid, then Equal reports true only if both are invalid.
-//
-// Scalar values are compared with the equivalent of the == operator in Go,
-// except bytes values which are compared using bytes.Equal and
-// floating point values which specially treat NaNs as equal.
-// Message values are compared by recursively calling Equal.
-// Lists are equal if each element value is also equal.
-// Maps are equal if they have the same set of keys, where the pair of values
-// for each key is also equal.
func Equal(x, y Message) bool {
if x == nil || y == nil {
return x == nil && y == nil
@@ -42,130 +46,7 @@
if mx.IsValid() != my.IsValid() {
return false
}
- return equalMessage(mx, my)
-}
-
-// equalMessage compares two messages.
-func equalMessage(mx, my protoreflect.Message) bool {
- if mx.Descriptor() != my.Descriptor() {
- return false
- }
-
- nx := 0
- equal := true
- mx.Range(func(fd protoreflect.FieldDescriptor, vx protoreflect.Value) bool {
- nx++
- vy := my.Get(fd)
- equal = my.Has(fd) && equalField(fd, vx, vy)
- return equal
- })
- if !equal {
- return false
- }
- ny := 0
- my.Range(func(fd protoreflect.FieldDescriptor, vx protoreflect.Value) bool {
- ny++
- return true
- })
- if nx != ny {
- return false
- }
-
- return equalUnknown(mx.GetUnknown(), my.GetUnknown())
-}
-
-// equalField compares two fields.
-func equalField(fd protoreflect.FieldDescriptor, x, y protoreflect.Value) bool {
- switch {
- case fd.IsList():
- return equalList(fd, x.List(), y.List())
- case fd.IsMap():
- return equalMap(fd, x.Map(), y.Map())
- default:
- return equalValue(fd, x, y)
- }
-}
-
-// equalMap compares two maps.
-func equalMap(fd protoreflect.FieldDescriptor, x, y protoreflect.Map) bool {
- if x.Len() != y.Len() {
- return false
- }
- equal := true
- x.Range(func(k protoreflect.MapKey, vx protoreflect.Value) bool {
- vy := y.Get(k)
- equal = y.Has(k) && equalValue(fd.MapValue(), vx, vy)
- return equal
- })
- return equal
-}
-
-// equalList compares two lists.
-func equalList(fd protoreflect.FieldDescriptor, x, y protoreflect.List) bool {
- if x.Len() != y.Len() {
- return false
- }
- for i := x.Len() - 1; i >= 0; i-- {
- if !equalValue(fd, x.Get(i), y.Get(i)) {
- return false
- }
- }
- return true
-}
-
-// equalValue compares two singular values.
-func equalValue(fd protoreflect.FieldDescriptor, x, y protoreflect.Value) bool {
- switch fd.Kind() {
- case protoreflect.BoolKind:
- return x.Bool() == y.Bool()
- case protoreflect.EnumKind:
- return x.Enum() == y.Enum()
- case protoreflect.Int32Kind, protoreflect.Sint32Kind,
- protoreflect.Int64Kind, protoreflect.Sint64Kind,
- protoreflect.Sfixed32Kind, protoreflect.Sfixed64Kind:
- return x.Int() == y.Int()
- case protoreflect.Uint32Kind, protoreflect.Uint64Kind,
- protoreflect.Fixed32Kind, protoreflect.Fixed64Kind:
- return x.Uint() == y.Uint()
- case protoreflect.FloatKind, protoreflect.DoubleKind:
- fx := x.Float()
- fy := y.Float()
- if math.IsNaN(fx) || math.IsNaN(fy) {
- return math.IsNaN(fx) && math.IsNaN(fy)
- }
- return fx == fy
- case protoreflect.StringKind:
- return x.String() == y.String()
- case protoreflect.BytesKind:
- return bytes.Equal(x.Bytes(), y.Bytes())
- case protoreflect.MessageKind, protoreflect.GroupKind:
- return equalMessage(x.Message(), y.Message())
- default:
- return x.Interface() == y.Interface()
- }
-}
-
-// equalUnknown compares unknown fields by direct comparison on the raw bytes
-// of each individual field number.
-func equalUnknown(x, y protoreflect.RawFields) bool {
- if len(x) != len(y) {
- return false
- }
- if bytes.Equal([]byte(x), []byte(y)) {
- return true
- }
-
- mx := make(map[protoreflect.FieldNumber]protoreflect.RawFields)
- my := make(map[protoreflect.FieldNumber]protoreflect.RawFields)
- for len(x) > 0 {
- fnum, _, n := protowire.ConsumeField(x)
- mx[fnum] = append(mx[fnum], x[:n]...)
- x = x[n:]
- }
- for len(y) > 0 {
- fnum, _, n := protowire.ConsumeField(y)
- my[fnum] = append(my[fnum], y[:n]...)
- y = y[n:]
- }
- return reflect.DeepEqual(mx, my)
+ vx := protoreflect.ValueOfMessage(mx)
+ vy := protoreflect.ValueOfMessage(my)
+ return vx.Equal(vy)
}
diff --git a/reflect/protoreflect/value_equal.go b/reflect/protoreflect/value_equal.go
new file mode 100644
index 0000000..5916525
--- /dev/null
+++ b/reflect/protoreflect/value_equal.go
@@ -0,0 +1,168 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package protoreflect
+
+import (
+ "bytes"
+ "fmt"
+ "math"
+ "reflect"
+
+ "google.golang.org/protobuf/encoding/protowire"
+)
+
+// Equal reports whether v1 and v2 are recursively equal.
+//
+// - Values of different types are always unequal.
+//
+// - Bytes values are equal if they contain identical bytes.
+// Empty bytes (regardless of nil-ness) are considered equal.
+//
+// - Floating point values are equal if they contain the same value.
+// Unlike the == operator, a NaN is equal to another NaN.
+//
+// - Enums are equal if they contain the same number.
+// Since Value does not contain an enum descriptor,
+// enum values do not consider the type of the enum.
+//
+// - Other scalar values are equal if they contain the same value.
+//
+// - Message values are equal if they belong to the same message descriptor,
+// have the same set of populated known and extension field values,
+// and the same set of unknown fields values.
+//
+// - Lists are equal if they are the same length and
+// each corresponding element is equal.
+//
+// - Maps are equal if they have the same set of keys and
+// the corresponding value for each key is equal.
+func (v1 Value) Equal(v2 Value) bool {
+ return equalValue(v1, v2)
+}
+
+func equalValue(x, y Value) bool {
+ eqType := x.typ == y.typ
+ switch x.typ {
+ case nilType:
+ return eqType
+ case boolType:
+ return eqType && x.Bool() == y.Bool()
+ case int32Type, int64Type:
+ return eqType && x.Int() == y.Int()
+ case uint32Type, uint64Type:
+ return eqType && x.Uint() == y.Uint()
+ case float32Type, float64Type:
+ return eqType && equalFloat(x.Float(), y.Float())
+ case stringType:
+ return eqType && x.String() == y.String()
+ case bytesType:
+ return eqType && bytes.Equal(x.Bytes(), y.Bytes())
+ case enumType:
+ return eqType && x.Enum() == y.Enum()
+ default:
+ switch x := x.Interface().(type) {
+ case Message:
+ y, ok := y.Interface().(Message)
+ return ok && equalMessage(x, y)
+ case List:
+ y, ok := y.Interface().(List)
+ return ok && equalList(x, y)
+ case Map:
+ y, ok := y.Interface().(Map)
+ return ok && equalMap(x, y)
+ default:
+ panic(fmt.Sprintf("unknown type: %T", x))
+ }
+ }
+}
+
+// equalFloat compares two floats, where NaNs are treated as equal.
+func equalFloat(x, y float64) bool {
+ if math.IsNaN(x) || math.IsNaN(y) {
+ return math.IsNaN(x) && math.IsNaN(y)
+ }
+ return x == y
+}
+
+// equalMessage compares two messages.
+func equalMessage(mx, my Message) bool {
+ if mx.Descriptor() != my.Descriptor() {
+ return false
+ }
+
+ nx := 0
+ equal := true
+ mx.Range(func(fd FieldDescriptor, vx Value) bool {
+ nx++
+ vy := my.Get(fd)
+ equal = my.Has(fd) && equalValue(vx, vy)
+ return equal
+ })
+ if !equal {
+ return false
+ }
+ ny := 0
+ my.Range(func(fd FieldDescriptor, vx Value) bool {
+ ny++
+ return true
+ })
+ if nx != ny {
+ return false
+ }
+
+ return equalUnknown(mx.GetUnknown(), my.GetUnknown())
+}
+
+// equalList compares two lists.
+func equalList(x, y List) bool {
+ if x.Len() != y.Len() {
+ return false
+ }
+ for i := x.Len() - 1; i >= 0; i-- {
+ if !equalValue(x.Get(i), y.Get(i)) {
+ return false
+ }
+ }
+ return true
+}
+
+// equalMap compares two maps.
+func equalMap(x, y Map) bool {
+ if x.Len() != y.Len() {
+ return false
+ }
+ equal := true
+ x.Range(func(k MapKey, vx Value) bool {
+ vy := y.Get(k)
+ equal = y.Has(k) && equalValue(vx, vy)
+ return equal
+ })
+ return equal
+}
+
+// equalUnknown compares unknown fields by direct comparison on the raw bytes
+// of each individual field number.
+func equalUnknown(x, y RawFields) bool {
+ if len(x) != len(y) {
+ return false
+ }
+ if bytes.Equal([]byte(x), []byte(y)) {
+ return true
+ }
+
+ mx := make(map[FieldNumber]RawFields)
+ my := make(map[FieldNumber]RawFields)
+ for len(x) > 0 {
+ fnum, _, n := protowire.ConsumeField(x)
+ mx[fnum] = append(mx[fnum], x[:n]...)
+ x = x[n:]
+ }
+ for len(y) > 0 {
+ fnum, _, n := protowire.ConsumeField(y)
+ my[fnum] = append(my[fnum], y[:n]...)
+ y = y[n:]
+ }
+ return reflect.DeepEqual(mx, my)
+}
diff --git a/reflect/protoreflect/value_test.go b/reflect/protoreflect/value_test.go
index c6bbb58..d387900 100644
--- a/reflect/protoreflect/value_test.go
+++ b/reflect/protoreflect/value_test.go
@@ -11,10 +11,13 @@
"testing"
)
+var (
+ fakeMessage = new(struct{ Message })
+ fakeList = new(struct{ List })
+ fakeMap = new(struct{ Map })
+)
+
func TestValue(t *testing.T) {
- fakeMessage := new(struct{ Message })
- fakeList := new(struct{ List })
- fakeMap := new(struct{ Map })
tests := []struct {
in Value
@@ -98,6 +101,47 @@
}
}
+func TestValueEqual(t *testing.T) {
+ tests := []struct {
+ x, y Value
+ want bool
+ }{
+ {Value{}, Value{}, true},
+ {Value{}, ValueOfBool(true), false},
+ {ValueOfBool(true), ValueOfBool(true), true},
+ {ValueOfBool(true), ValueOfBool(false), false},
+ {ValueOfBool(false), ValueOfInt32(0), false},
+ {ValueOfInt32(0), ValueOfInt32(0), true},
+ {ValueOfInt32(0), ValueOfInt32(1), false},
+ {ValueOfInt32(0), ValueOfInt64(0), false},
+ {ValueOfInt64(123), ValueOfInt64(123), true},
+ {ValueOfFloat64(0), ValueOfFloat64(0), true},
+ {ValueOfFloat64(math.NaN()), ValueOfFloat64(math.NaN()), true},
+ {ValueOfFloat64(math.NaN()), ValueOfFloat64(0), false},
+ {ValueOfFloat64(math.Inf(1)), ValueOfFloat64(math.Inf(1)), true},
+ {ValueOfFloat64(math.Inf(-1)), ValueOfFloat64(math.Inf(1)), false},
+ {ValueOfBytes(nil), ValueOfBytes(nil), true},
+ {ValueOfBytes(nil), ValueOfBytes([]byte{}), true},
+ {ValueOfBytes(nil), ValueOfBytes([]byte{1}), false},
+ {ValueOfEnum(0), ValueOfEnum(0), true},
+ {ValueOfEnum(0), ValueOfEnum(1), false},
+ {ValueOfBool(false), ValueOfMessage(fakeMessage), false},
+ {ValueOfMessage(fakeMessage), ValueOfList(fakeList), false},
+ {ValueOfList(fakeList), ValueOfMap(fakeMap), false},
+ {ValueOfMap(fakeMap), ValueOfMessage(fakeMessage), false},
+
+ // Composite types are not tested here.
+ // See proto.TestEqual.
+ }
+
+ for _, tt := range tests {
+ got := tt.x.Equal(tt.y)
+ if got != tt.want {
+ t.Errorf("(%v).Equal(%v) = %v, want %v", tt.x, tt.y, got, tt.want)
+ }
+ }
+}
+
func BenchmarkValue(b *testing.B) {
const testdata = "The quick brown fox jumped over the lazy dog."
var sink1 string
