This interface is only ever used within the impl package.
Unexport it to avoid potential abuse by users.
Change-Id: I58d0cc2e8cb01c8c9d36cdec469c8d2196c4f836
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/193197
Reviewed-by: Damien Neil <dneil@google.com>
Change the storage type of ExtensionField from interface{} to
protoreflect.Value.
Replace the codec functions operating on interface{}s with ones
operating on Values.
Values are potentially more efficient, since they can represent
non-pointer types without allocation. This also reduces the number of
types used to represent field values.
Additionally, this change lays groundwork for changing the
user-visible representation of repeated extension fields from
*[]T to []T. The storage type for extension fields must support mutation
(thus *[]T currently); changing the storage type to a Value permits this
without the need to introduce yet another view on field values.
Change-Id: Ida336be14112bb940f655236eb58df21bf312525
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/192218
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
Add a way to typecheck a Value or interface{} without converting it to
the other form. This permits implementations which store field values as
a Value (such as dynamicpb, or (soon) extensions in generated messages)
to validate inputs without an unnecessary conversion.
Fixesgolang/protobuf#905
Change-Id: I1b78612b22ae832efbb55f81ae420871729e3a02
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/192457
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
We occasionally need to work with immutable, empty lists, maps, and
messages. Notably, Message.Get on an empty repeated field will return a
"frozen" empty value.
Move handling of these immutable, zero-length composites into Converter,
to unify the behavior of regular and extension fields.
Add a Zero method to Converter, MessageType, and ExtensionType, to
provide a consistent way to get an empty, frozen value of a composite
type. Adding this method to the public {Message,Extension}Type
interfaces does increase our API surface, but lets us (for example)
cleanly represent an empty map as a nil map rather than a non-nil
one wrapped in a frozenMap type.
Drop the frozen{List,Map,Message} types as no longer necessary.
(These types did have support for creating a read-only view of a
non-empty value, but we are not currently using that feature.)
Change-Id: Ia76f149d591da07b40ce75b7404a7ab8a60cb9d8
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/189339
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
Add methods to protoreflect.{Message,List,Map} to constrict values
assignable to a message field, list element, or map value. These
methods return the default value for scalar fields, the zero value for
scalar list elements and map values, and an empty, mutable value for
messages, lists, and maps.
Deprecate the NewMessage methods on these types, which are superseded.
Updates golang/protobuf#879
Change-Id: I0f064f60c89a239330ccea81523f559f14fd2c4f
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/188997
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
A Converter converts between reflect.Values and protoreflect.Values.
The existing usage of Converter is somewhat confusing: The
internal/value package creates Converters for scalar types only, the
internal/impl package creates Converters for legacy messages and enums,
and the reflect/prototype package creates Converters for repeated fields.
Change the Converter type to an interface. The constructor for
Converter takes a FieldDescriptor and reflect.Type, and directly
handles conversions for all field types: Scalars, lists, maps, and
legacy types.
Move Converter into the internal/impl package, since that package
contains the necessary support for dealing with legacy messages and
enums. Drop the internal/value package.
Replace two uses of prototype.Extension with more focused
implementations, since the implementation is trivial with the
refactored Converter. Drop prototype.Extension for the moment since
it is now unused.
Change-Id: If0c570fefac002cc5925b3d56281b6eb17e90d5f
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/187857
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
