7 Commits

Author SHA1 Message Date
Joe Tsai
acaef6adb7 cmd/protoc-gen-go: avoid referencing remote enum values by name
The Go generator has historically always prefixed an enum value
with the name of the enum type, when it was unnecessary to do so.

For example:
	enum Status {
		STATUS_FAILED = 0;
		STATUS_PASSED = 1;
	}
would be generated as:
	type Status int32
	const (
		Status_STATUS_FAILED Status = 0
		Status_STATUS_PASSED Status = 1
	)

It is common for the enum values to be manually prefixed by the
enum type since protobuf enums use C++ namespace rules where
enum types and enum values are in the same namespace scope.
Thus, having the Go generator add a prefix is redundant.
See https://github.com/golang/protobuf/issues/513.

Some custom Go generators like protoc-gen-gogo allow removing
the prefix with the gogoproto.goproto_enum_prefix feature.
However, this leads to interoperability issues between
protoc-gen-go and protoc-gen-gogo, where the enum value names
cannot be accurately inferred.

Avoid this problem by just hard-coding the enum value number
for values declared in other packages. This provides benefits
in interoperability at the small cost of enum values possibly
being stale if their value were ever changed in a remote package.
However, this would only occur with use of proto2 enums and
default values, which seems to be an exceptionally rare situation.

Before:
	Default_MyMessage_MyField = remotepb.FooEnum_FOO_ENUM
After:
	Default_MyMessage_MyField = remotepb.FooEnum(4) // remotepb.FooEnum_FOO_ENUM

Before:
	func (x *MyMessage) GetField() remotepb.FooEnum {
		...
		return remotepb.FooEnum_FOO_ZERO
	}
After:
	func (x *MyMessage) GetField() remotepb.FooEnum {
		...
		return remotepb.FooEnum(0) // always 0 for proto3 and often 0 for proto2
	}

Change-Id: I3a06cd553f2eaf6124666f6c36c196d500d35718
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/319649
Trust: Joe Tsai <joetsai@digital-static.net>
Reviewed-by: Damien Neil <dneil@google.com>
2021-05-24 22:21:56 +00:00
Joe Tsai
3ebaa92e92 all: use v2 Message interface for weak fields
Cleanup the generated logic by having the implementation be backed
by protoimpl rather that directly generated.

Weak fields are a deprecated feature of protobufs and
have entirely be superceded by extensions.
Unfortunately, there are still some usages of it.

Change-Id: Ie1a4b7da253e2ccf5e56627775d9b2fb4090d59a
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/229717
Reviewed-by: Damien Neil <dneil@google.com>
2020-04-29 22:34:29 +00:00
Damien Neil
3c5fb5f879 all: make .proto file names relative to module root
Change the protoc flags such that when one of our test .proto files
imports another, the filename is consistently specified relative to the
module root.

Change-Id: I690282795cef23347c8794c1c6357e4fe9560d8a
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/217762
Reviewed-by: Joe Tsai <joetsai@google.com>
2020-02-04 23:20:20 +00:00
Joe Tsai
8517608739 cmd/protoc-gen-go: remove json ignore tags
These are not necessary now that weak fields are unexported.

Change-Id: Ida18b984abedfdf52fd3d5f3cb2f4ca580659a5c
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/210745
Reviewed-by: Damien Neil <dneil@google.com>
2019-12-10 23:22:16 +00:00
Joe Tsai
4663ebc852 internal/genname: centralize the definitions for generated names
Both the generator and the runtime need to agree upon the names of
specialized Go struct fields. Centralize that information in an
internal genname package.

In the mean time, also change the XXX_weak field name to match
the name used internally at Google.

Change-Id: I026bf354418c363482e5902f21aa5e0cacae24b0
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/207080
Reviewed-by: Damien Neil <dneil@google.com>
2019-12-09 22:57:38 +00:00
Joe Tsai
ae313d4af3 cmd/protoc-gen-go: fix Reset method
The MessageInfo cache, once set, must not be cleared, otherwise
there exists a *messageState value where the MessageInfo value is nil.
Fix the generation of the Reset method to avoid clearing this value.

Change-Id: Ic84ca8b2640a43e967c36993da1ccd3f2b7096c4
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/201478
Reviewed-by: Damien Neil <dneil@google.com>
2019-10-17 17:10:14 +00:00
Joe Tsai
26aef9d6d6 cmd/protoc-gen-go: add support for field-tracking
Field-tracking is an experimental feature in the Go linker
where it statically tracks whether a Go struct field is used.
This CL modifies the generator to emit special markers that
tells the linker to know which fields to track.

Change-Id: I235da3f3d6c0ef2021b5fe1c16106ebb8fd6f557
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/189558
Reviewed-by: Damien Neil <dneil@google.com>
2019-08-26 17:54:17 +00:00