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Diffstat (limited to 'vendor/google.golang.org/protobuf/proto/extension.go')
-rw-r--r-- | vendor/google.golang.org/protobuf/proto/extension.go | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/vendor/google.golang.org/protobuf/proto/extension.go b/vendor/google.golang.org/protobuf/proto/extension.go new file mode 100644 index 00000000..5f293cda --- /dev/null +++ b/vendor/google.golang.org/protobuf/proto/extension.go @@ -0,0 +1,92 @@ +// Copyright 2019 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 proto + +import ( + "google.golang.org/protobuf/reflect/protoreflect" +) + +// HasExtension reports whether an extension field is populated. +// It returns false if m is invalid or if xt does not extend m. +func HasExtension(m Message, xt protoreflect.ExtensionType) bool { + // Treat nil message interface as an empty message; no populated fields. + if m == nil { + return false + } + + // As a special-case, we reports invalid or mismatching descriptors + // as always not being populated (since they aren't). + if xt == nil || m.ProtoReflect().Descriptor() != xt.TypeDescriptor().ContainingMessage() { + return false + } + + return m.ProtoReflect().Has(xt.TypeDescriptor()) +} + +// ClearExtension clears an extension field such that subsequent +// HasExtension calls return false. +// It panics if m is invalid or if xt does not extend m. +func ClearExtension(m Message, xt protoreflect.ExtensionType) { + m.ProtoReflect().Clear(xt.TypeDescriptor()) +} + +// GetExtension retrieves the value for an extension field. +// If the field is unpopulated, it returns the default value for +// scalars and an immutable, empty value for lists or messages. +// It panics if xt does not extend m. +func GetExtension(m Message, xt protoreflect.ExtensionType) interface{} { + // Treat nil message interface as an empty message; return the default. + if m == nil { + return xt.InterfaceOf(xt.Zero()) + } + + return xt.InterfaceOf(m.ProtoReflect().Get(xt.TypeDescriptor())) +} + +// SetExtension stores the value of an extension field. +// It panics if m is invalid, xt does not extend m, or if type of v +// is invalid for the specified extension field. +func SetExtension(m Message, xt protoreflect.ExtensionType, v interface{}) { + xd := xt.TypeDescriptor() + pv := xt.ValueOf(v) + + // Specially treat an invalid list, map, or message as clear. + isValid := true + switch { + case xd.IsList(): + isValid = pv.List().IsValid() + case xd.IsMap(): + isValid = pv.Map().IsValid() + case xd.Message() != nil: + isValid = pv.Message().IsValid() + } + if !isValid { + m.ProtoReflect().Clear(xd) + return + } + + m.ProtoReflect().Set(xd, pv) +} + +// RangeExtensions iterates over every populated extension field in m in an +// undefined order, calling f for each extension type and value encountered. +// It returns immediately if f returns false. +// While iterating, mutating operations may only be performed +// on the current extension field. +func RangeExtensions(m Message, f func(protoreflect.ExtensionType, interface{}) bool) { + // Treat nil message interface as an empty message; nothing to range over. + if m == nil { + return + } + + m.ProtoReflect().Range(func(fd protoreflect.FieldDescriptor, v protoreflect.Value) bool { + if fd.IsExtension() { + xt := fd.(protoreflect.ExtensionTypeDescriptor).Type() + vi := xt.InterfaceOf(v) + return f(xt, vi) + } + return true + }) +} |