protogen: generate .meta file with code annotations

When the generator parameter 'annotate_code' is provided, generate a .meta
file containing a GeneratedCodeInfo message describing the generated code's
relation to the source .proto file.

Annotations are added with (*protogen.GeneratedFile).Annotate, which takes the
name of a Go identifier (e.g., "SomeMessage" or "SomeMessage.GetField") and an
associated source location. The generator examines the generated AST to
determine source offsets for the symbols.

Change the []int32 "Path" in protogen types to a "Location", which also captures
the source file name.

Change-Id: Icd2340875831f40a1f91d495e3bd7ea381475c77
Reviewed-on: https://go-review.googlesource.com/c/139759
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
11 files changed
tree: f9eb4ecd6a9868644c80fd5ad2233026494b0ac7
  1. cmd/
  2. internal/
  3. protogen/
  4. reflect/
  5. .gitignore
  6. .travis.yml
  7. AUTHORS
  8. CONTRIBUTING.md
  9. CONTRIBUTORS
  10. go.mod
  11. go.sum
  12. LICENSE
  13. PATENTS
  14. README.md
  15. regenerate.bash
  16. test.bash
README.md

Next Generation Go Protocol Buffers

WARNING: This repository is in active development. There are no guarantees about API stability. Breaking changes will occur until a stable release is made and announced.

This repository is for the development of the next major Go implementation of protocol buffers. This library makes breaking API changes relative to the existing Go protobuf library. Of particular note, this API aims to make protobuf reflection a first-class feature of the API and implements the protobuf ecosystem in terms of reflection.

Design Documents

List of relevant design documents:

Contributing

We appreciate community contributions. See CONTRIBUTING.md.

Reporting Issues

Issues regarding the new API can be filed at github.com/golang/protobuf. Please use a APIv2: prefix in the title to make it clear that the issue is regarding the new API work.