Function extractStacktrace

tests/qunit/qunit.js:1332–1369

( e, offset )

// Later Safari and IE10 are supposed to support error.stack as well
// See also https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Error/Stack
function extractStacktrace( e, offset ) {
	offset = offset === undefined ? 3 : offset;

	var stack, include, i;

	if ( e.stacktrace ) {
		// Opera
		return e.stacktrace.split( "\n" )[ offset + 3 ];
	} else if ( e.stack ) {
		// Firefox, Chrome
		stack = e.stack.split( "\n" );
		if (/^error$/i.test( stack[0] ) ) {
			stack.shift();
		}
		if ( fileName ) {
			include = [];
			for ( i = offset; i < stack.length; i++ ) {
				if ( stack[ i ].indexOf( fileName ) !== -1 ) {
					break;
				}
				include.push( stack[ i ] );
			}
			if ( include.length ) {
				return include.join( "\n" );
			}
		}
		return stack[ offset ];
	} else if ( e.sourceURL ) {
		// Safari, PhantomJS
		// hopefully one day Safari provides actual stacktraces
		// exclude useless self-reference for generated Error objects
		if ( /qunit.js$/.test( e.sourceURL ) ) {
			return;
		}
		// for actual exceptions, this is useful
		return e.sourceURL + ":" + e.line;
	}
}
function sourceFromStacktrace( offset ) {
	try {
		throw new Error();