make DateOffset immutable #21341
Returning to the long-standing goal of making
Earlier attempts in this direction tried to make the base class a
Note: this PR does not implement the caching that is the underlying goal.
I'm likely to make some other PRs in this area, will try to keep them orthogonal.
@@ Coverage Diff @@ ## master #21341 +/- ## ========================================= Coverage ? 91.91% ========================================= Files ? 153 Lines ? 49550 Branches ? 0 ========================================= Hits ? 45546 Misses ? 4004 Partials ? 0