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Use prepareStackTrace to get the filename & line number
/**
* Use CallSite to extract filename and number, for more info read: https://v8.dev/docs/stack-trace-api#customizing-stack-traces
* @returns {string} filename and line number separated by a colon
*/
const getFileNameAndLineNumber = () => {
const oldStackTrace = Error.prepareStackTrace;
try {
// eslint-disable-next-line handle-callback-err
Error.prepareStackTrace = (err, structuredStackTrace) => structuredStackTrace;
Error.captureStackTrace(this);
// in this example I needed to "peel" the first CallSites in order to get to the caller we're looking for
// in your code, the number of stacks depends on the levels of abstractions you're using
// in my code I'm stripping frames that come from logger module and winston (node_module)
const callSite = this.stack.find(line => line.getFileName().indexOf('/logger/') < 0 && line.getFileName().indexOf('/node_modules/') < 0);
return callSite.getFileName() + ':' + callSite.getLineNumber();
} finally {
Error.prepareStackTrace = oldStackTrace;
}
};
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