use char to find instead of string (#10094)

* [Bazel] Add a doc explaining our C++ build systems and distribution archives. (#10073)

* use char to find instead of string

Co-authored-by: David L. Jones <dlj@google.com>

src/google/protobuf/compiler/csharp/csharp_helpers.cc

@@ -107,7 +107,7 @@ CSharpType GetCSharpType(FieldDescriptor::Type type) {
 }
 
 std::string StripDotProto(const std::string& proto_file) {
-  int lastindex = proto_file.find_last_of(".");
+  int lastindex = proto_file.find_last_of('.');
   return proto_file.substr(0, lastindex);
 }
 
@@ -122,7 +122,7 @@ std::string GetFileNamespace(const FileDescriptor* descriptor) {
 // input of "google/protobuf/foo_bar.proto" would result in "FooBar".
 std::string GetFileNameBase(const FileDescriptor* descriptor) {
     std::string proto_file = descriptor->name();
-    int lastslash = proto_file.find_last_of("/");
+    int lastslash = proto_file.find_last_of('/');
     std::string base = proto_file.substr(lastslash + 1);
     return UnderscoresToPascalCase(StripDotProto(base));
 }
@@ -422,7 +422,7 @@ std::string GetOutputFile(const FileDescriptor* descriptor,
       return ""; // This will be ignored, because we've set an error.
     }
     namespace_suffix = ns.substr(base_namespace.length());
-    if (namespace_suffix.find(".") == 0) {
+    if (namespace_suffix.find('.') == 0) {
       namespace_suffix = namespace_suffix.substr(1);
     }
   }

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

@@ -128,7 +128,7 @@ void EnumGenerator::GenerateHeader(io::Printer* printer) {
       continue;
     }
     if (all_values_[i]->GetSourceLocation(&location)) {
-      std::string comments = BuildCommentsString(location, true).c_str();
+      std::string comments = BuildCommentsString(location, true);
       if (comments.length() > 0) {
         if (i > 0) {
           printer->Print("\n");

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

@@ -990,9 +990,9 @@ static std::string HandleExtremeFloatingPoint(std::string val,
     return "-INFINITY";
   } else {
     // float strings with ., e or E need to have f appended
-    if (add_float_suffix && (val.find(".") != std::string::npos ||
-                             val.find("e") != std::string::npos ||
-                             val.find("E") != std::string::npos)) {
+    if (add_float_suffix && (val.find('.') != std::string::npos ||
+                             val.find('e') != std::string::npos ||
+                             val.find('E') != std::string::npos)) {
       val += "f";
     }
     return val;

src/google/protobuf/compiler/php/php_generator.cc

@@ -334,7 +334,7 @@ std::string GeneratedMetadataFileName(const FileDescriptor* file,
                                       const Options& options) {
   const std::string& proto_file = file->name();
   int start_index = 0;
-  int first_index = proto_file.find_first_of("/", start_index);
+  int first_index = proto_file.find_first_of('/', start_index);
   std::string result = "";
   std::string segment = "";
 
@@ -347,7 +347,7 @@ std::string GeneratedMetadataFileName(const FileDescriptor* file,
 
   // Append directory name.
   std::string file_no_suffix;
-  int lastindex = proto_file.find_last_of(".");
+  int lastindex = proto_file.find_last_of('.');
   if (proto_file == kEmptyFile) {
     return kEmptyMetadataFile;
   } else {
@@ -371,12 +371,12 @@ std::string GeneratedMetadataFileName(const FileDescriptor* file,
           file_no_suffix.substr(start_index, first_index - start_index), true);
       result += ReservedNamePrefix(segment, file) + segment + "/";
       start_index = first_index + 1;
-      first_index = file_no_suffix.find_first_of("/", start_index);
+      first_index = file_no_suffix.find_first_of('/', start_index);
     }
   }
 
   // Append file name.
-  int file_name_start = file_no_suffix.find_last_of("/");
+  int file_name_start = file_no_suffix.find_last_of('/');
   if (file_name_start == std::string::npos) {
     file_name_start = 0;
   } else {
@@ -475,7 +475,7 @@ std::string PhpSetterTypeName(const FieldDescriptor* field,
   }
   if (field->is_repeated()) {
     // accommodate for edge case with multiple types.
-    size_t start_pos = type.find("|");
+    size_t start_pos = type.find('|');
     if (start_pos != std::string::npos) {
       type.replace(start_pos, 1, ">|array<");
     }
@@ -1207,7 +1207,7 @@ void GenerateHead(const FileDescriptor* file, io::Printer* printer) {
 }
 
 std::string FilenameToClassname(const std::string& filename) {
-  int lastindex = filename.find_last_of(".");
+  int lastindex = filename.find_last_of('.');
   std::string result = filename.substr(0, lastindex);
   for (int i = 0; i < result.size(); i++) {
     if (result[i] == '/') {
@@ -1227,7 +1227,7 @@ void GenerateMetadataFile(const FileDescriptor* file, const Options& options,
   GenerateHead(file, &printer);
 
   std::string fullname = FilenameToClassname(filename);
-  int lastindex = fullname.find_last_of("\\");
+  int lastindex = fullname.find_last_of('\\');
 
   if (lastindex != std::string::npos) {
     printer.Print(
@@ -1263,7 +1263,7 @@ void GenerateEnumFile(const FileDescriptor* file, const EnumDescriptor* en,
   GenerateHead(file, &printer);
 
   std::string fullname = FilenameToClassname(filename);
-  int lastindex = fullname.find_last_of("\\");
+  int lastindex = fullname.find_last_of('\\');
 
   if (lastindex != std::string::npos) {
     printer.Print(
@@ -1391,7 +1391,7 @@ void GenerateMessageFile(const FileDescriptor* file, const Descriptor* message,
   GenerateHead(file, &printer);
 
   std::string fullname = FilenameToClassname(filename);
-  int lastindex = fullname.find_last_of("\\");
+  int lastindex = fullname.find_last_of('\\');
 
   if (lastindex != std::string::npos) {
     printer.Print(
@@ -1508,7 +1508,7 @@ void GenerateServiceFile(
   GenerateHead(file, &printer);
 
   std::string fullname = FilenameToClassname(filename);
-  int lastindex = fullname.find_last_of("\\");
+  int lastindex = fullname.find_last_of('\\');
 
   if (!file->options().php_namespace().empty() ||
       (!file->options().has_php_namespace() && !file->package().empty()) ||

src/google/protobuf/compiler/ruby/ruby_generator.cc

@@ -68,7 +68,7 @@ std::string NumberToString(numeric_type value) {
 }
 
 std::string GetRequireName(const std::string& proto_file) {
-  int lastindex = proto_file.find_last_of(".");
+  int lastindex = proto_file.find_last_of('.');
   return proto_file.substr(0, lastindex) + "_pb";
 }
 
@@ -421,7 +421,7 @@ int GeneratePackageModules(const FileDescriptor* file, io::Printer* printer) {
     //    -> A.B.C
     if (package_name.find("::") != std::string::npos) {
       need_change_to_module = false;
-    } else if (package_name.find(".") != std::string::npos) {
+    } else if (package_name.find('.') != std::string::npos) {
       GOOGLE_LOG(WARNING) << "ruby_package option should be in the form of:"
                           << " 'A::B::C' and not 'A.B.C'";
     }