This patch mechanically replaces None with std::nullopt where the
compiler would warn if None were deprecated. The intent is to reduce
the amount of manual work required in migrating from Optional to
std::optional.
This is part of an effort to migrate from llvm::Optional to
std::optional:
https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
Printing support enables the production of more useful error messages in unit testing e.g. when using matchers such as `UnorderedElementsAre()` to inspect the contents of a `StringMap`.
Reviewed By: gribozavr2, sgatev, ymandel
Differential Revision: https://reviews.llvm.org/D132747
Default the moves and delete the copies for TempFile, matching TempDir
and TempLink, and add tests for all of them to confirm that the
destructor is not harmful after it has been moved from.
Differential Revision: https://reviews.llvm.org/D120691
Kazu Hirata