From 549842deccc58476c2f697be57eca3ecbcb93d60 Mon Sep 17 00:00:00 2001
From: maleo <maleo@google.com>
Date: Thu, 4 Jan 2024 14:49:35 +0000
Subject: [PATCH] Prefer go_grpc_library

This allows for easier compiler upgrades via rules_go upgrades
---
 language/go/config.go    |  4 ++--
 language/go/constants.go |  6 +++---
 language/go/fix.go       | 10 +++++-----
 language/go/generate.go  | 17 +++++++++++------
 4 files changed, 21 insertions(+), 16 deletions(-)

diff --git a/language/go/config.go b/language/go/config.go
index e23ed5437..b11e06d72 100644
--- a/language/go/config.go
+++ b/language/go/config.go
@@ -147,8 +147,8 @@ const (
 )
 
 var (
-	defaultGoProtoCompilers = []string{"@io_bazel_rules_go//proto:go_proto"}
-	defaultGoGrpcCompilers  = []string{"@io_bazel_rules_go//proto:go_grpc"}
+	defaultGoProtoCompilers = []string{}
+	defaultGoGrpcCompilers  = []string{}
 )
 
 func (m testMode) String() string {
diff --git a/language/go/constants.go b/language/go/constants.go
index 0affc48a9..5bb33e68d 100644
--- a/language/go/constants.go
+++ b/language/go/constants.go
@@ -31,9 +31,9 @@ const (
 	// mode for libraries that contained .pb.go files and .proto files.
 	legacyProtoFilegroupName = "go_default_library_protos"
 
-	// grpcCompilerLabel is the label for the gRPC compiler plugin, used in the
-	// "compilers" attribute of go_proto_library rules.
-	grpcCompilerLabel = "@io_bazel_rules_go//proto:go_grpc"
+	// oldGrpcCompilerLabel is the label for the old gRPC compiler plugin, used
+	// in the "compilers" attribute of go_proto_library rules.
+	oldGrpcCompilerLabel = "@io_bazel_rules_go//proto:go_grpc"
 
 	// goProtoSuffix is the suffix applied to the labels of all generated
 	// go_proto_library targets.
diff --git a/language/go/fix.go b/language/go/fix.go
index 6d31add74..c3f0fa4e0 100644
--- a/language/go/fix.go
+++ b/language/go/fix.go
@@ -171,15 +171,15 @@ func migrateLibraryEmbed(c *config.Config, f *rule.File) {
 	}
 }
 
-// migrateGrpcCompilers converts "go_grpc_library" rules into "go_proto_library"
-// rules with a "compilers" attribute.
+// migrateGrpcCompilers converts "go_proto_library" rules with a "compilers"
+// attribute equal to oldGrpcCompilerLabel into "go_grpc_library" rules.
 func migrateGrpcCompilers(c *config.Config, f *rule.File) {
 	for _, r := range f.Rules {
-		if r.Kind() != "go_grpc_library" || r.ShouldKeep() || r.Attr("compilers") != nil {
+		if r.Kind() != "go_proto_library" || r.ShouldKeep() || r.Attr("compilers") == nil || len(r.Attr("compilers")) != 1 || r.Attr("compilers")[0] != oldGrpcCompilerLabel {
 			continue
 		}
-		r.SetKind("go_proto_library")
-		r.SetAttr("compilers", []string{grpcCompilerLabel})
+		r.SetKind("go_grpc_library")
+		r.SetAttr("compilers", []string{})
 	}
 }
 
diff --git a/language/go/generate.go b/language/go/generate.go
index 53e397a12..a0f480f7e 100644
--- a/language/go/generate.go
+++ b/language/go/generate.go
@@ -454,14 +454,19 @@ func (g *generator) generateProto(mode proto.Mode, target protoTarget, importPat
 		}
 	}
 
-	goProtoLibrary := rule.NewRule("go_proto_library", goProtoName)
+	var goProtoLibrary *rule.Rule
+	if target.hasServices && !gc.goGrpcCompilersSet {
+		goProtoLibrary := rule.NewRule("go_grpc_library", goProtoName)
+	} else {
+		goProtoLibrary := rule.NewRule("go_proto_library", goProtoName)
+		if gc.goProtoCompilersSet {
+			goProtoLibrary.SetAttr("compilers", gc.goProtoCompilers)
+		} else if gc.goGrpcCompilersSet {
+			goProtoLibrary.SetAttr("compilers", gc.goGrpcCompilers)
+		}
+	}
 	goProtoLibrary.SetAttr("proto", ":"+protoName)
 	g.setImportAttrs(goProtoLibrary, importPath)
-	if target.hasServices {
-		goProtoLibrary.SetAttr("compilers", gc.goGrpcCompilers)
-	} else if gc.goProtoCompilersSet {
-		goProtoLibrary.SetAttr("compilers", gc.goProtoCompilers)
-	}
 	if g.shouldSetVisibility {
 		goProtoLibrary.SetAttr("visibility", visibility)
 	}