cmd/protoc-gen-go-grpc: add protoc change detector test

.github/workflows/testing.yml

@@ -37,8 +37,6 @@ jobs:
   # Run the main gRPC-Go tests.
   tests:
     # Proto checks are run in the above job.
-    env:
-      VET_SKIP_PROTO: 1
     runs-on: ubuntu-latest
     timeout-minutes: 20
     strategy:
@@ -98,14 +96,20 @@ jobs:
 
       # Only run vet for 'vet' runs.
       - name: Run vet.sh
+        env:
+          VET_SKIP_PROTO: 1
         if: matrix.type == 'vet'
         run: ./vet.sh -install && ./vet.sh
 
       # Main tests run for everything except when testing "extras"
       # (where we run a reduced set of tests).
       - name: Run tests
         if: matrix.type == 'tests'
+        env:
+          VET_BUILD_GO_PROTOC: 1
         run: |
+          ./vet.sh -install
+          protoc --version
           go version
           go test ${{ matrix.testflags }} -cpu 1,4 -timeout 7m google.golang.org/grpc/...
           cd "${GITHUB_WORKSPACE}"

cmd/protoc-gen-go-grpc/grpc_test.go

@@ -0,0 +1,97 @@
+/*
+ *
+ * Copyright 2024 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package main
+
+import (
+	"os"
+	"os/exec"
+	"reflect"
+	"strings"
+	"testing"
+)
+
+func TestProtocBinary(t *testing.T) {
+	workingDir, err := os.Getwd()
+	if err != nil {
+		t.Fatalf("failed to get current working directory: %v", err)
+	}
+
+	tmpDir, err := os.MkdirTemp(workingDir, "test")
+	if err != nil {
+		t.Fatalf("error creating temp dir: %v", err)
+	}
+
+	defer t.Cleanup(func() {
+		err := os.RemoveAll(tmpDir)
+		if err != nil {
+			t.Fatalf("error removing temp dir and all test files: %v", err)
+		}
+	})
+
+	protocPath, err := exec.LookPath("protoc")
+	if err != nil {
+		t.Fatalf("protoc not found in PATH: %v", err)
+	}
+
+	for _, spec := range []struct {
+		protoFile string
+	}{
+		{
+			protoFile: "test_unary.proto",
+		},
+		{
+			protoFile: "test_server_streaming.proto",
+		},
+		{
+			protoFile: "test_client_streaming.proto",
+		},
+		{
+			protoFile: "test_bidirectional_streaming.proto",
+		},
+	} {
+		protoFilePath := "./proto/" + spec.protoFile
+		if _, err := os.Stat(protoFilePath); os.IsNotExist(err) {
+			t.Fatalf("proto file %s does not exist", protoFilePath)
+		}
+
+		command := exec.Command(protocPath, "--go-grpc_out="+tmpDir, protoFilePath)
+		command.Dir = workingDir
+
+		output, err := command.CombinedOutput()
+		if err != nil {
+			t.Fatalf("failed to execute command protoc: %v\n%s", err, output)
+		}
+
+		pbgoFile := strings.Replace(spec.protoFile, ".proto", "_grpc.pb.go", 1)
+
+		testPluginContent, err := os.ReadFile(tmpDir + "/testdata/proto/" + pbgoFile)
+		if err != nil {
+			t.Errorf("error while reading proto file generated from test: %s", err)
+		}
+
+		protocPluginContent, err := os.ReadFile("./testdata/proto/" + pbgoFile)
+		if err != nil {
+			t.Errorf("error while reading proto file generated from protoc command: %s", err)
+		}
+
+		if !reflect.DeepEqual(testPluginContent, protocPluginContent) {
+			t.Errorf("error generated go test stubs are not equal")
+		}
+	}
+}

cmd/protoc-gen-go-grpc/proto/test_bidirectional_streaming.proto

@@ -0,0 +1,31 @@
+// Copyright 2024 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+syntax = "proto3";
+
+option go_package = "testdata/proto";
+
+package main;
+
+message EventRequest {
+  bytes content = 1;
+}
+
+message EventResponse {
+  bytes content = 1;
+}
+
+service BidirectionalStreamingService {
+  rpc bidirectionalMethod(stream EventRequest) returns (stream EventResponse) {}
+}

cmd/protoc-gen-go-grpc/proto/test_client_streaming.proto

@@ -0,0 +1,31 @@
+// Copyright 2024 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+syntax = "proto3";
+
+option go_package = "testdata/proto";
+
+package main;
+
+message EventRequest {
+  bytes content = 1;
+}
+
+message EventResponse {
+  bytes content = 1;
+}
+
+service ClientStreamingService {
+  rpc clientMethod(stream EventRequest) returns (EventResponse) {}
+}

cmd/protoc-gen-go-grpc/proto/test_server_streaming.proto

@@ -0,0 +1,31 @@
+// Copyright 2024 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+syntax = "proto3";
+
+option go_package = "testdata/proto";
+
+package main;
+
+message EventRequest {
+  bytes content = 1;
+}
+
+message EventResponse {
+  bytes content = 1;
+}
+
+service ServerStreamingService {
+  rpc serverMethod(EventRequest) returns (stream EventResponse) {};
+}

cmd/protoc-gen-go-grpc/proto/test_unary.proto

@@ -0,0 +1,31 @@
+// Copyright 2024 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+syntax = "proto3";
+
+option go_package = "testdata/proto";
+
+package main;
+
+message EventRequest {
+  bytes content = 1;
+}
+
+message EventResponse {
+  bytes content = 1;
+}
+
+service UnaryService {
+  rpc unaryMethod(EventRequest) returns (EventResponse) {}
+}