Commit Graph

8 Commits

Author SHA1 Message Date
Damien Neil
a8593bae57 reflect/protoreflect: drop the ProtoEnum type
Drop the protoreflect.ProtoEnum type (containing a single method
returning a protoreflect.Enum) and make generated enum types
directly implement protoreflect.Enum instead.

Messages have a two-level type split (ProtoMessage and Message) to
minimize conflicts between reflection methods and field names. Enums
need no such split, since enums do not have fields and therefore have
no source of conflicts.

Change-Id: I2b6222e9404253e6bfef2217859e1b760ffcd29b
Reviewed-on: https://go-review.googlesource.com/c/156902
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
Reviewed-by: Damien Neil <dneil@google.com>
2019-01-09 00:40:35 +00:00
Joe Tsai
9667c4816d cmd/protoc-gen-go: reduce technical debt
The following TODOs were addressed:
* Consistently collect all enums, messages, and extensions in a breadth-first order.
The practical affect of this is that the declaration order in a Go file may change.
This simplifies reflection generation, which relies on consistent ordering.
* Removal of placeholder declarations (e.g., "var _ = proto.Marshal") since
protogen is intelligent about including imports as necessary.
* Always generate a default variable or constant for explicit empty strings.
The practical effect of this is the addition of new declarations in some cases.
However, it simplifies our logic such that it matches the protobuf data model.
* Generate the registration statements in a consistent order.

Change-Id: I627bb72589432bb65d53b50965ea88e5f7983977
Reviewed-on: https://go-review.googlesource.com/c/152778
Reviewed-by: Damien Neil <dneil@google.com>
2018-12-07 03:13:48 +00:00
Joe Tsai
b6405bd782 cmd/protoc-gen-go: add support for protobuf reflection
Implement support in protoc-gen-go for generating messages and enums
that satisfy the v2 protobuf reflection interfaces. Specifically, the following
are added:
* top-level variable representing the file descriptor
* ProtoReflect method on enums (to implement protoV2.Enum)
* ProtoReflect method on messages (to implement protoV2.Message)

The following are not supported yet:
* resolving transitive dependencies for file imports
* Extension descriptors
* Service descriptors

The implementation approach creates a single array for all the message and enum
declarations and references sections of that array to complete dependencies.
Since protobuf declarations can form a graph (a message may depend on itself),
it is difficult to construct a graph as a single literal. One way is to use
placeholder descriptors, but that is not efficient as it requires encoding
the full name of each dependent enum and message and then later resolving it;
thus, both expanding the binary size and also increasing initialization cost.
Instead, we add a prototype.{Enum,Message}.Reference method to obtain a
descriptor reference for the purposes for satisfying dependencies.
As such, nested declarations and dependencies are populated in an init function.

Other changes to support the implementation:
* Added a protoimpl package to expose the MessageType type and also the
MessageTypeOf and EnumTypeOf helper functions.
* Added a protogen.File.GoIdent field to provide a suggested variable name
for the file descriptor.
* Added prototype.{Enum,Message}.Reference that provides a descriptor reference
for the purposes for satisfying cyclic dependencies.
* Added protoreflect.{Syntax,Cardinality,Kind}.GoString to obtain a Go source
identifier that represents the given constant.

Change-Id: I9455764882dee6ad10f251901e7d419091e8bf1d
Reviewed-on: https://go-review.googlesource.com/c/150074
Reviewed-by: Damien Neil <dneil@google.com>
2018-12-05 19:32:12 +00:00
Joe Tsai
d7e97bc71b cmd/protoc-gen-go: generate XXX_OneofWrappers instead of XXX_OneofFuncs
The marshaler, unmarshaler, and sizer functions are unused ever since
the underlying implementation was switched to be table-driven.
Change the function to only return the wrapper structs.

This change:
* enables generated protos to drop dependencies on certain proto types
* reduces the size of generated protos
* simplifies the implementation of oneofs in protoc-gen-go

Updates #708

Change-Id: I845c9009bc0236d1b51d34b014dc3e184303c0f2
Reviewed-on: https://go-review.googlesource.com/c/151357
Reviewed-by: Damien Neil <dneil@google.com>
2018-11-27 19:36:27 +00:00
Damien Neil
154da98aa5 cmd/protoc-gen-go: special cases for MessageSet extensions
Add special-case handling for extension fields named
"message_set_extension" that extend a message_set_wire_format message.

Support special cases for a proto1 feature that was superseded by proto2
extensions.

Change-Id: Icbdb711111c66be547bf8d6f37ab3079c320e2a1
Reviewed-on: https://go-review.googlesource.com/136536
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
2018-09-24 17:25:31 +00:00
Damien Neil
1ec3315873 protoc-gen-go: generate imports consistent with previous protoc-gen-go
Include references to the proto, fmt, and math packages, consistent with
the ones in the previous generator:

	// Reference imports to suppress errors if they are not otherwise used.
	var _ = proto.Marshal
	var _ = fmt.Errorf
	var _ = math.Inf

Sort imports with ast.SortImports to ensure gofmt-compatible output.

Copy the protoc-gen-go/testdata/imports test files from
github.com/golang/protobuf.

Change-Id: I263e2ac750d03596ae9cb23609049d5ef1016205
Reviewed-on: https://go-review.googlesource.com/135361
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
2018-09-14 22:40:55 +00:00
Damien Neil
d412792d34 cmd/protoc-gen-go: reference proto.ProtoPackageIsVersionX
Include the compile-time assertion that the generated file is compatible
with the proto package it is being compiled against.

Change-Id: Iefa27ee3a99a6669a93303b6674b0033794ba0be
Reviewed-on: https://go-review.googlesource.com/134995
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
2018-09-12 20:08:45 +00:00
Damien Neil
46abb57549 cmd/protoc-gen-go: generate enums
This produces exactly the same output (to the best of my ability to
determine) as github.com/golang/protobuf.

Change-Id: Ib60e7a836efb1eb0e5167b30458049ec239e7903
Reviewed-on: https://go-review.googlesource.com/134695
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
2018-09-11 21:42:46 +00:00