src/vs/editor/contrib/format/browser/format.ts/alertFormattingEdits
export function alertFormattingEdits(edits: ISingleEditOperation[]): void {

	edits = edits.filter(edit => edit.range);
	if (!edits.length) {
		return;
	}

	let { range } = edits[0];
	for (let i = 1; i < edits.length; i++) {
		range = Range.plusRange(range, edits[i].range);
	}
	const { startLineNumber, endLineNumber } = range;
	if (startLineNumber === endLineNumber) {
		if (edits.length === 1) {
			alert(nls.localize('hint11', "Made 1 formatting edit on line {0}", startLineNumber));
		} else {
			alert(nls.localize('hintn1', "Made {0} formatting edits on line {1}", edits.length, startLineNumber));
		}
	} else {
		if (edits.length === 1) {
			alert(nls.localize('hint1n', "Made 1 formatting edit between lines {0} and {1}", startLineNumber, endLineNumber));
		} else {
			alert(nls.localize('hintnn', "Made {0} formatting edits between lines {1} and {2}", edits.length, startLineNumber, endLineNumber));
		}
	}
}