Clarify jsonpb package docs.

jsonpb/jsonpb.go

@@ -30,12 +30,11 @@
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 /*
-Package jsonpb provides marshaling/unmarshaling functionality between
+Package jsonpb provides marshaling and unmarshaling between protocol buffers and JSON.
-protocol buffer and JSON objects.
+It follows the specification at https://developers.google.com/protocol-buffers/docs/proto3#json.
 
-Compared to encoding/json, this library:
+This package produces a different output than the standard "encoding/json" package,
- - encodes int64, uint64 as strings
+which does not operate correctly on protocol buffers.
- - optionally encodes enums as integers
 */
 package jsonpb
 

protoc-gen-go/generator/generator.go

@@ -2541,7 +2541,9 @@ func (g *Generator) generateFileDescriptor(file *FileDescriptor) {
 	w.Close()
 	b = buf.Bytes()
 
-	g.P("var fileDescriptor", file.index, " = []byte{")
+	v := fmt.Sprintf("fileDescriptor%d", file.index)
+	g.P()
+	g.P("var ", v, " = []byte{")
 	g.In()
 	g.P("// ", len(b), " bytes of a gzipped FileDescriptorProto")
 	for len(b) > 0 {