Add support for using generated protos w/o output_to_workspace (#118)

Author: douglas-reid

protobuf/internal/proto_compile.bzl

@@ -331,17 +331,26 @@ def _build_protobuf_out(run, builder):
   """Build the --{lang}_out option"""
   lang = run.lang
   name = lang.pb_plugin_name or lang.name
-  outdir = builder.get(lang.name + "_outdir", run.outdir)
   options = builder.get(lang.name + "_pb_options", [])
 
+  if run.data.protos[0].path.startswith(run.ctx.var["GENDIR"]):
+    outdir = "."
+  else:
+    outdir = builder.get(lang.name + "_outdir", run.outdir)
+
   _build_plugin_out(name, outdir, options, builder)
 
 
 def _build_grpc_out(run, builder):
   """Build the --{lang}_out grpc option"""
   lang = run.lang
   name = lang.grpc_plugin_name or "grpc-" + lang.name
-  outdir = builder.get(lang.name + "_outdir", run.outdir)
+
+  if run.data.protos[0].path.startswith(run.ctx.var["GENDIR"]):
+    outdir = "."
+  else:
+    outdir = builder.get(lang.name + "_outdir", run.outdir)
+
   options = builder.get(lang.name + "_grpc_options", [])
 
   _build_plugin_out(name, outdir, options, builder)

tests/generated_proto_file/BUILD

@@ -0,0 +1,34 @@
+package(default_visibility = ["//visibility:public"])
+
+load("//cpp:rules.bzl", "cpp_proto_library")
+load("//go:rules.bzl", "go_proto_library")
+
+genrule(
+     name = "copy_file",
+     srcs = ["simple.proto"],
+     outs = ["copy.proto"],
+     cmd = "cat $(location simple.proto) > $@",
+     message = "copy",
+)
+
+cpp_proto_library(
+   name = "default_library",
+   protos = ["simple.proto"],
+)
+
+cpp_proto_library(
+   name = "copy_library",
+   protos = ["copy.proto"],   
+   with_grpc = True,
+)
+
+go_proto_library(
+   name = "go_default_library",
+   protos = ["simple.proto"],
+)
+
+go_proto_library(
+   name = "go_copy_library",
+   protos = ["copy.proto"],
+   with_grpc = True,
+)

tests/generated_proto_file/simple.proto

@@ -0,0 +1,7 @@
+syntax = "proto3";
+
+package simple;
+
+message Test {
+    string value = 1;
+}