Migrate std::operator+ to Abseil helpers in Objective-c compiler dire…

…ctory.

This also opportunistically migrates many C-style and STL strings to string_view in touched code.

PiperOrigin-RevId: 502774859

src/google/protobuf/compiler/objectivec/enum_field.cc

@@ -147,8 +147,10 @@ RepeatedEnumFieldGenerator::RepeatedEnumFieldGenerator(
 
 void RepeatedEnumFieldGenerator::FinishInitialization() {
   RepeatedFieldGenerator::FinishInitialization();
-  variables_["array_comment"] = "// |" + variables_["name"] + "| contains |" +
-                                variables_["storage_type"] + "|\n";
+  std::string name = variables_["name"];
+  std::string storage_type = variables_["storage_type"];
+  variables_["array_comment"] =
+      absl::StrCat("// |", name, "| contains |", storage_type, "|\n");
 }
 
 // NOTE: RepeatedEnumFieldGenerator::DetermineForwardDeclarations isn't needed

src/google/protobuf/compiler/objectivec/extension.cc

@@ -48,10 +48,11 @@ namespace protobuf {
 namespace compiler {
 namespace objectivec {
 
-ExtensionGenerator::ExtensionGenerator(const std::string& root_class_name,
+ExtensionGenerator::ExtensionGenerator(absl::string_view root_class_name,
                                        const FieldDescriptor* descriptor)
     : method_name_(ExtensionMethodName(descriptor)),
-      root_class_and_method_name_(root_class_name + "_" + method_name_),
+      root_class_and_method_name_(
+          absl::StrCat(root_class_name, "_", method_name_)),
       descriptor_(descriptor) {
   if (descriptor->is_map()) {
     // NOTE: src/google/protobuf/compiler/plugin.cc makes use of cerr for some
@@ -120,11 +121,11 @@ void ExtensionGenerator::GenerateStaticVariablesInitialization(
     vars["default"] = DefaultValue(descriptor_);
   }
   std::string type = GetCapitalizedType(descriptor_);
-  vars["extension_type"] = std::string("GPBDataType") + type;
+  vars["extension_type"] = absl::StrCat("GPBDataType", type);
 
   if (objc_type == OBJECTIVECTYPE_ENUM) {
     vars["enum_desc_func_name"] =
-        EnumName(descriptor_->enum_type()) + "_EnumDescriptor";
+        absl::StrCat(EnumName(descriptor_->enum_type()), "_EnumDescriptor");
   } else {
     vars["enum_desc_func_name"] = "NULL";
   }

src/google/protobuf/compiler/objectivec/extension.h

@@ -44,7 +44,7 @@ namespace objectivec {
 
 class ExtensionGenerator {
  public:
-  ExtensionGenerator(const std::string& root_class_name,
+  ExtensionGenerator(absl::string_view root_class_name,
                      const FieldDescriptor* descriptor);
   ~ExtensionGenerator() = default;
 

src/google/protobuf/compiler/objectivec/field.cc

@@ -82,7 +82,7 @@ void SetCommonFieldVariables(
   (*variables)["capitalized_name"] = capitalized_name;
   (*variables)["raw_field_name"] = raw_field_name;
   (*variables)["field_number_name"] =
-      classname + "_FieldNumber_" + capitalized_name;
+      absl::StrCat(classname, "_FieldNumber_", capitalized_name);
   (*variables)["field_number"] = absl::StrCat(descriptor->number());
   (*variables)["field_type"] = GetCapitalizedType(descriptor);
   (*variables)["deprecated_attribute"] =
@@ -120,8 +120,8 @@ void SetCommonFieldVariables(
   (*variables)["dataTypeSpecific_name"] = "clazz";
   (*variables)["dataTypeSpecific_value"] = "Nil";
 
-  (*variables)["storage_offset_value"] = "(uint32_t)offsetof(" + classname +
-                                         "__storage_, " + camel_case_name + ")";
+  (*variables)["storage_offset_value"] = absl::StrCat(
+      "(uint32_t)offsetof(", classname, "__storage_, ", camel_case_name, ")");
   (*variables)["storage_offset_comment"] = "";
 
   // Clear some common things so they can be set just when needed.

src/google/protobuf/compiler/objectivec/generator.cc

@@ -145,8 +145,9 @@ bool ObjectiveCGenerator::GenerateAll(
       // Default is "no".
       if (!StringToBool(options[i].second,
                         &validation_options.prefixes_must_be_registered)) {
-        *error = "error: Unknown value for prefixes_must_be_registered: " +
-                 options[i].second;
+        *error = absl::StrCat(
+            "error: Unknown value for prefixes_must_be_registered: ",
+            options[i].second);
         return false;
       }
     } else if (options[i].first == "require_prefixes") {
@@ -158,8 +159,8 @@ bool ObjectiveCGenerator::GenerateAll(
       // Default is "no".
       if (!StringToBool(options[i].second,
                         &validation_options.require_prefixes)) {
-        *error =
-            "error: Unknown value for require_prefixes: " + options[i].second;
+        *error = absl::StrCat("error: Unknown value for require_prefixes: ",
+                              options[i].second);
         return false;
       }
     } else if (options[i].first == "generate_for_named_framework") {
@@ -229,7 +230,8 @@ bool ObjectiveCGenerator::GenerateAll(
       if (StringToBool(options[i].second, &value)) {
         SetUseProtoPackageAsDefaultPrefix(value);
       } else {
-        *error = "error: Unknown use_package_as_prefix: " + options[i].second;
+        *error = absl::StrCat("error: Unknown use_package_as_prefix: ",
+                              options[i].second);
         return false;
       }
     } else if (options[i].first == "proto_package_prefix_exceptions_path") {
@@ -251,8 +253,9 @@ bool ObjectiveCGenerator::GenerateAll(
     } else if (options[i].first == "headers_use_forward_declarations") {
       if (!StringToBool(options[i].second,
                         &generation_options.headers_use_forward_declarations)) {
-        *error = "error: Unknown value for headers_use_forward_declarations: " +
-                 options[i].second;
+        *error = absl::StrCat(
+            "error: Unknown value for headers_use_forward_declarations: ",
+            options[i].second);
         return false;
       }
     } else if (options[i].first == "experimental_multi_source_generation") {
@@ -267,13 +270,14 @@ bool ObjectiveCGenerator::GenerateAll(
       if (!StringToBool(
               options[i].second,
               &generation_options.experimental_multi_source_generation)) {
-        *error =
-            "error: Unknown value for experimental_multi_source_generation: " +
-            options[i].second;
+        *error = absl::StrCat(
+            "error: Unknown value for experimental_multi_source_generation: ",
+            options[i].second);
         return false;
       }
     } else {
-      *error = "error: Unknown generator option: " + options[i].first;
+      *error =
+          absl::StrCat("error: Unknown generator option: ", options[i].first);
       return false;
     }
   }
@@ -312,7 +316,8 @@ bool ObjectiveCGenerator::GenerateAll(
 
     // Generate header.
     {
-      auto output = absl::WrapUnique(context->Open(filepath + ".pbobjc.h"));
+      auto output =
+          absl::WrapUnique(context->Open(absl::StrCat(filepath, ".pbobjc.h")));
       io::Printer printer(output.get());
       file_generator.GenerateHeader(&printer);
       if (printer.failed()) {
@@ -367,7 +372,8 @@ bool ObjectiveCGenerator::GenerateAll(
           }
         }
       } else {
-        auto output = absl::WrapUnique(context->Open(filepath + ".pbobjc.m"));
+        auto output = absl::WrapUnique(
+            context->Open(absl::StrCat(filepath, ".pbobjc.m")));
         io::Printer printer(output.get());
         file_generator.GenerateSource(&printer);
         if (printer.failed()) {

src/google/protobuf/compiler/objectivec/helpers.cc

@@ -39,6 +39,7 @@
 #include "absl/strings/match.h"
 #include "absl/strings/str_replace.h"
 #include "absl/strings/str_split.h"
+#include "absl/strings/string_view.h"
 #include "google/protobuf/compiler/objectivec/names.h"
 #include "google/protobuf/io/strtod.h"
 #include "google/protobuf/stubs/common.h"
@@ -97,7 +98,7 @@ std::string HandleExtremeFloatingPoint(std::string val, bool add_float_suffix) {
     if (add_float_suffix &&
         (absl::StrContains(val, '.') || absl::StrContains(val, 'e') ||
          absl::StrContains(val, 'E'))) {
-      val += "f";
+      return absl::StrCat(val, "f");
     }
     return val;
   }
@@ -255,15 +256,15 @@ std::string DefaultValue(const FieldDescriptor* field) {
       }
       return absl::StrCat(field->default_value_int32());
     case FieldDescriptor::CPPTYPE_UINT32:
-      return absl::StrCat(field->default_value_uint32()) + "U";
+      return absl::StrCat(field->default_value_uint32(), "U");
     case FieldDescriptor::CPPTYPE_INT64:
       // gcc and llvm reject the decimal form of kint32min and kint64min.
       if (field->default_value_int64() == LLONG_MIN) {
         return "-0x8000000000000000LL";
       }
-      return absl::StrCat(field->default_value_int64()) + "LL";
+      return absl::StrCat(field->default_value_int64(), "LL");
     case FieldDescriptor::CPPTYPE_UINT64:
-      return absl::StrCat(field->default_value_uint64()) + "ULL";
+      return absl::StrCat(field->default_value_uint64(), "ULL");
     case FieldDescriptor::CPPTYPE_DOUBLE:
       return HandleExtremeFloatingPoint(
           io::SimpleDtoa(field->default_value_double()), false);
@@ -274,7 +275,7 @@ std::string DefaultValue(const FieldDescriptor* field) {
       return field->default_value_bool() ? "YES" : "NO";
     case FieldDescriptor::CPPTYPE_STRING: {
       const bool has_default_value = field->has_default_value();
-      const std::string& default_string = field->default_value_string();
+      absl::string_view default_string = field->default_value_string();
       if (!has_default_value || default_string.length() == 0) {
         // If the field is defined as being the empty string,
         // then we will just assign to nil, as the empty string is the
@@ -292,10 +293,12 @@ std::string DefaultValue(const FieldDescriptor* field) {
         // a cstring.
         uint32_t length = ghtonl(default_string.length());
         std::string bytes((const char*)&length, sizeof(length));
-        bytes.append(default_string);
-        return "(NSData*)\"" + EscapeTrigraphs(absl::CEscape(bytes)) + "\"";
+        absl::StrAppend(&bytes, default_string);
+        return absl::StrCat("(NSData*)\"",
+                            EscapeTrigraphs(absl::CEscape(bytes)), "\"");
       } else {
-        return "@\"" + EscapeTrigraphs(absl::CEscape(default_string)) + "\"";
+        return absl::StrCat(
+            "@\"", EscapeTrigraphs(absl::CEscape(default_string)), "\"");
       }
     }
     case FieldDescriptor::CPPTYPE_ENUM:
@@ -317,7 +320,8 @@ std::string BuildFlagsString(FlagType flag_type,
   } else if (strings.size() == 1) {
     return strings[0];
   }
-  std::string string("(" + GetEnumNameForFlagType(flag_type) + ")(");
+  std::string string =
+      absl::StrCat("(", GetEnumNameForFlagType(flag_type), ")(");
   for (size_t i = 0; i != strings.size(); ++i) {
     if (i > 0) {
       string.append(" | ");
@@ -328,20 +332,20 @@ std::string BuildFlagsString(FlagType flag_type,
   return string;
 }
 
-std::string ObjCClass(const std::string& class_name) {
-  return std::string("GPBObjCClass(") + class_name + ")";
+std::string ObjCClass(absl::string_view class_name) {
+  return absl::StrCat("GPBObjCClass(", class_name, ")");
 }
 
-std::string ObjCClassDeclaration(const std::string& class_name) {
-  return std::string("GPBObjCClassDeclaration(") + class_name + ");";
+std::string ObjCClassDeclaration(absl::string_view class_name) {
+  return absl::StrCat("GPBObjCClassDeclaration(", class_name, ");");
 }
 
 std::string BuildCommentsString(const SourceLocation& location,
                                 bool prefer_single_line) {
-  const std::string& comments = location.leading_comments.empty()
-                                    ? location.trailing_comments
-                                    : location.leading_comments;
-  std::vector<std::string> lines;
+  absl::string_view comments = location.leading_comments.empty()
+                                   ? location.trailing_comments
+                                   : location.leading_comments;
+  std::vector<absl::string_view> lines;
   lines = absl::StrSplit(comments, '\n', absl::AllowEmpty());
   while (!lines.empty() && lines.back().empty()) {
     lines.pop_back();
@@ -364,7 +368,7 @@ std::string BuildCommentsString(const SourceLocation& location,
   } else {
     prefix = "* ";
     suffix = "\n";
-    final_comments += "/**\n";
+    absl::StrAppend(&final_comments, "/**\n");
     epilogue = " **/\n";
     add_leading_space = true;
   }
@@ -382,11 +386,10 @@ std::string BuildCommentsString(const SourceLocation& location,
     absl::StripAsciiWhitespace(&line);
     // If not a one line, need to add the first space before *, as
     // absl::StripAsciiWhitespace would have removed it.
-    line = (add_leading_space ? " " : "") + line;
-    final_comments += line + suffix;
+    line = absl::StrCat(add_leading_space ? " " : "", line);
+    absl::StrAppend(&final_comments, line, suffix);
   }
-  final_comments += epilogue;
-  return final_comments;
+  return absl::StrCat(final_comments, epilogue);
 }
 
 }  // namespace objectivec

src/google/protobuf/compiler/objectivec/helpers.h

@@ -105,11 +105,11 @@ std::string BuildFlagsString(FlagType type,
 
 // Returns a symbol that can be used in C code to refer to an Objective C
 // class without initializing the class.
-std::string ObjCClass(const std::string& class_name);
+std::string ObjCClass(absl::string_view class_name);
 
 // Declares an Objective C class without initializing the class so that it can
 // be refrerred to by ObjCClass.
-std::string ObjCClassDeclaration(const std::string& class_name);
+std::string ObjCClassDeclaration(absl::string_view class_name);
 
 // Builds HeaderDoc/appledoc style comments out of the comments in the .proto
 // file.
@@ -134,20 +134,14 @@ std::string GetOptionalDeprecatedAttribute(const TDescriptor* descriptor,
     std::string message;
     const FileDescriptor* sourceFile = descriptor->file();
     if (isFileLevelDeprecation) {
-      message = sourceFile->name() + " is deprecated.";
+      message = absl::StrCat(sourceFile->name(), " is deprecated.");
     } else {
-      message = descriptor->full_name() + " is deprecated (see " +
-                sourceFile->name() + ").";
+      message = absl::StrCat(descriptor->full_name(), " is deprecated (see ",
+                             sourceFile->name(), ").");
     }
 
-    std::string result = std::string("GPB_DEPRECATED_MSG(\"") + message + "\")";
-    if (preSpace) {
-      result.insert(0, " ");
-    }
-    if (postNewline) {
-      result.append("\n");
-    }
-    return result;
+    return absl::StrCat(preSpace ? " " : "", "GPB_DEPRECATED_MSG(\"", message,
+                        "\")", postNewline ? "\n" : "");
   } else {
     return "";
   }

src/google/protobuf/compiler/objectivec/import_writer.cc

@@ -134,9 +134,8 @@ void ImportWriter::AddFile(const FileDescriptor* file,
     // in other cases, they get skipped because the generated code already
     // import GPBProtocolBuffers.h and hence proves them.
     if (for_bundled_proto_) {
-      const std::string header_name =
-          "GPB" + FilePathBasename(file) + header_extension;
-      protobuf_imports_.push_back(header_name);
+      protobuf_imports_.emplace_back(
+          absl::StrCat("GPB", FilePathBasename(file), header_extension));
     }
     return;
   }
@@ -148,15 +147,15 @@ void ImportWriter::AddFile(const FileDescriptor* file,
 
   auto proto_lookup = proto_file_to_framework_name_.find(file->name());
   if (proto_lookup != proto_file_to_framework_name_.end()) {
-    other_framework_imports_.push_back(
-        proto_lookup->second + "/" + FilePathBasename(file) + header_extension);
+    other_framework_imports_.emplace_back(absl::StrCat(
+        proto_lookup->second, "/", FilePathBasename(file), header_extension));
     return;
   }
 
   if (!generate_for_named_framework_.empty()) {
-    other_framework_imports_.push_back(generate_for_named_framework_ + "/" +
-                                       FilePathBasename(file) +
-                                       header_extension);
+    other_framework_imports_.push_back(
+        absl::StrCat(generate_for_named_framework_, "/", FilePathBasename(file),
+                     header_extension));
     return;
   }
 

src/google/protobuf/compiler/objectivec/line_consumer.cc

@@ -161,11 +161,11 @@ bool Parser::Finish(std::string* out_error) {
 
 }  // namespace
 
-bool ParseSimpleFile(const std::string& path, LineConsumer* line_consumer,
+bool ParseSimpleFile(absl::string_view path, LineConsumer* line_consumer,
                      std::string* out_error) {
   int fd;
   do {
-    fd = posix::open(path.c_str(), O_RDONLY);
+    fd = posix::open(std::string(path).c_str(), O_RDONLY);
   } while (fd < 0 && errno == EINTR);
   if (fd < 0) {
     *out_error =
@@ -179,7 +179,7 @@ bool ParseSimpleFile(const std::string& path, LineConsumer* line_consumer,
 }
 
 bool ParseSimpleStream(io::ZeroCopyInputStream& input_stream,
-                       const std::string& stream_name,
+                       absl::string_view stream_name,
                        LineConsumer* line_consumer, std::string* out_error) {
   std::string local_error;
   Parser parser(line_consumer);

src/google/protobuf/compiler/objectivec/line_consumer.h

@@ -55,12 +55,12 @@ class PROTOC_EXPORT LineConsumer {
   virtual bool ConsumeLine(absl::string_view line, std::string* out_error) = 0;
 };
 
-bool PROTOC_EXPORT ParseSimpleFile(const std::string& path,
+bool PROTOC_EXPORT ParseSimpleFile(absl::string_view path,
                                    LineConsumer* line_consumer,
                                    std::string* out_error);
 
 bool PROTOC_EXPORT ParseSimpleStream(io::ZeroCopyInputStream& input_stream,
-                                     const std::string& stream_name,
+                                     absl::string_view stream_name,
                                      LineConsumer* line_consumer,
                                      std::string* out_error);
 

src/google/protobuf/compiler/objectivec/line_consumer_unittest.cc

@@ -55,7 +55,7 @@ class TestLineCollector : public LineConsumer {
   bool ConsumeLine(absl::string_view line, std::string* out_error) override {
     if (reject_ && *reject_ == line) {
       if (!skip_msg_) {
-        *out_error = std::string("Rejected '") + *reject_ + "'";
+        *out_error = absl::StrCat("Rejected '", *reject_, "'");
       }
       return false;
     }