resolveDartLibrary function
Resolve the library rooted at mainPath (with part directives) into a
single concatenated source string with extension methods merged into
their target class bodies.
Implementation
String resolveDartLibrary(String mainPath) {
final mainFile = File(mainPath);
final mainDir = mainFile.parent.path.replaceAll('\\', '/');
final mainSource = mainFile.readAsStringSync();
return resolveDartLibraryFromSource(
mainSource,
partLoader: (uri) => File('$mainDir/$uri').readAsStringSync(),
);
}