src/vs/editor/common/diff/standardLinesDiffComputer.ts/getCategory
function getCategory(charCode: number): CharBoundaryCategory {
	if (charCode === CharCode.LineFeed) {
		return CharBoundaryCategory.LineBreakLF;
	} else if (charCode === CharCode.CarriageReturn) {
		return CharBoundaryCategory.LineBreakCR;
	} else if (isSpace(charCode)) {
		return CharBoundaryCategory.Space;
	} else if (charCode >= CharCode.a && charCode <= CharCode.z) {
		return CharBoundaryCategory.WordLower;
	} else if (charCode >= CharCode.A && charCode <= CharCode.Z) {
		return CharBoundaryCategory.WordUpper;
	} else if (charCode >= CharCode.Digit0 && charCode <= CharCode.Digit9) {
		return CharBoundaryCategory.WordNumber;
	} else if (charCode === -1) {
		return CharBoundaryCategory.End;
	} else {
		return CharBoundaryCategory.Other;
	}
}