AppCenter: Find and replace string in a file during build

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";
}