AppCenter: Find and replace string in a file during build - visual-studio-app-center

Question

Is it possible to edit a .mm file before it gets compiled in AppCenter?
In an attempt to fix a build error, I want to find and replace a string in ../node_modules/react-native/React/CxxBridge/RCTCxxBridge.mm.
I tried using sed -i 's/oldString/newString/g' ../node_modules/react-native/React/CxxBridge/RCTCxxBridge.mm inside appcenter-pre-build.sh but it does not work.
Any help will be appreciated,
Thanks.

Answer 1

Not sure if this is your case, but I needed to update a version number on a complex project. To replace the counter of the current version with a new one, I considered updating the file with each build. After some versions of bash scripts, I realized that it's easier for me to write a console application in C with a couple of parameters to solve this problem. Works almost perfect for me. If you need I can share the simple code of this program.

Answer 2

Here is the C code that looks for a string in the file passed as a parameter and replaces the version number in it.
int main(int argc, char* argv[])
{
cout << "Version changer start\n";
if (argc < 2) {
cout << "There is no path argument. Version was no changed.";
return 1;
}
string sourcePath = argv[1];
string targetPath = sourcePath + ".tmp";
bool firstLine = true;
cout << sourcePath << endl;
ifstream sourceFile(sourcePath); // open file for input
ofstream targetFile(targetPath); // open file for output
string line;
while (getline(sourceFile, line)) // for each line read from the file
{
// looking for the desired line
if (line.find("public static String VER") != std::string::npos) { // replace "public static String VER" to your string definition code
line.replace(0, 32, "");
line.replace(line.length() - 2, 2, "");
int number = atoi(line.c_str());
number++; // In my case, I get an integer and add one to it
string v = to_string(number);
line = " public static String VER = \"" + v + "\";";
cout << v;
}
if (firstLine) {
targetFile << line;
firstLine = false;
}
else
targetFile << endl << line;
}
sourceFile.close();
targetFile.close();
remove(sourcePath.c_str());
if (rename(targetPath.c_str(), sourcePath.c_str()) != 0)
perror("Error renaming file");
else
cout << endl << "----------- done -----------\n";
}