forked from catchorg/Catch2
Martin Hořeňovský
fc5bc1fa8b
The old implementation of String matchers worked by making a, potentially lower-cased, copy of both the constructor arg, and the arg to `match` calls. The new implementation does not make copies, and instead does per-character lowering if needed. This is a win in **most** cases, with two exceptions: 1) Case-insensitive `Equals` between long strings. The old implementation is easy to autovectorize by the compiler, which wins over the extra copy with sufficiently long inputs. 2) Case-insensitive `ContainsSubstring` with inputs that trigger the worst case complexity of O(m*n) of the naive implementation. The latter is fixable with some elbow grease by implementing a proper string search algorithm, but the former is a cost we have to live with.