Protobuf: changed all exceptions in generated code into error codes. See description of particular codes in "error_codes"

proto/compiler/google/src/google/protobuf/compiler/kotlin/error_codes

@@ -0,0 +1,3 @@
+1 - mismatch of expected and actual WireType in parseFieldFrom method
+2 - read message of size that exceeds expected in parseFromWithSize method
+3 - read message of size that is not equal to expected. Can occur when deserializing nested message (code generated in C++ method generateSerializationMethods)

proto/compiler/google/src/google/protobuf/compiler/kotlin/src/kotlin_class_generator.cc

@@ -21,16 +21,21 @@ void ClassGenerator::generateCode(io::Printer *printer, bool isBuilder) const {
     generateHeader(printer, isBuilder);
     printer->Indent();
 
-    /**
-    * Field generator should know if it is generating code for builder.
-    * or for fair class to choose between 'val' and 'var'.
-    * Also note that fields should be declared before init section.
-    */
+    /*
+     * Field generator should know if it is generating code for builder
+     * or for fair class to choose between 'val' and 'var'.
+     * Also note that fields should be declared before init section.
+     */
+
     for (FieldGenerator *gen: properties) {
         gen->generateCode(printer, isBuilder);
         printer->Print("\n");
     }
 
+    // Generate field for errors code
+    printer->Print("\n");
+    printer->Print("var errorCode: Int = 0\n");
+
     printer->Print("\n");
     generateInitSection(printer);
 
@@ -298,13 +303,7 @@ void ClassGenerator::generateParseMethods(io::Printer *printer) const {
         printer->Indent();
 
         // check that wire type of that field is equal to expected
-        printer->Print(vars, "if (wireType != $kotlinWireType$) {\n");
-        printer->Indent();
-        printer->Print(vars, "throw InvalidProtocolBufferException(\""
-                               "Error: Field number $fieldNumber$ has wire type $kotlinWireType$"
-                               " but read $dl${wireType.toString()}\")");
-        printer->Outdent();
-        printer->Print("}\n");
+        printer->Print(vars, "if (wireType != $kotlinWireType$) { errorCode = 1; return false } \n");
 
         properties[i]->generateSerializationCode(printer, /* isRead = */ true, /* noTag = */ true);
 
@@ -340,7 +339,7 @@ void ClassGenerator::generateParseMethods(io::Printer *printer) const {
     vars["dollar"] = "$";
     printer->Print(vars,
                    "if (getSizeNoTag() > expectedSize) { "
-                           "throw InvalidProtocolBufferException(\"Error: expected size of message $dollar$expectedSize, but have read at least $dollar${getSizeNoTag()}\") "
+                           "errorCode = 2 "
                            "}\n");
 
     printer->Print("return this\n");

proto/compiler/google/src/google/protobuf/compiler/kotlin/src/kotlin_enum_generator.cc

@@ -44,15 +44,14 @@ void EnumGenerator::generateCode(io::Printer * printer) const {
     // Generate enum values.
     for (int i = 0; i < enumValues.size(); ++i) {
         enumValues[i]->generateCode(printer);
-        if (i + 1 != enumValues.size()) {
-            printer->Print(",");
-        }
-        else {
-            printer->Print(";");    // semicolon is necessary as companion object will follow
-        }
+        printer->Print(",");
         printer->Print("\n");
     }
 
+    // Generate additional value that will indicate errors in parsing this enum from int
+    vars["size"] = std::to_string(enumValues.size());
+    printer->Print(vars, "Unexpected($size$);\n");
+
     printer->Print("\n");
     generateEnumConverter(printer);
 
@@ -86,9 +85,7 @@ void EnumGenerator::generateEnumConverter(io::Printer *printer) const {
 
     // catch cast errors in else-clause
     printer->Print(vars,
-                   "else -> throw InvalidProtocolBufferException("
-                           "\"Error: got unexpected int $dollar${ord} while parsing $type$ \""
-                           ");\n");
+                   "else -> Unexpected\n");
 
     printer->Outdent();     // when-clause
     printer->Print("}\n");

proto/compiler/google/src/google/protobuf/compiler/kotlin/src/kotlin_field_generator.cc

@@ -257,10 +257,7 @@ void FieldGenerator::generateSerializationForMessages(io::Printer * printer, boo
                        "$fieldName$.mergeFromWithSize(input, expectedSize)\n");
 
         // check that actual size equal to expected size
-        printer->Print(vars, "if (expectedSize != $fieldName$.getSizeNoTag()) { "
-                "throw InvalidProtocolBufferException ("
-                "\"Expected size $dollar${expectedSize} got $dollar${$fieldName$.getSizeNoTag()}"
-                "\") }\n");
+        printer->Print(vars, "if (expectedSize != $fieldName$.getSizeNoTag()) { errorCode = 3; return false }\n");
         printer->Outdent();
         printer->Print("}\n");
     }