mirror of
https://github.com/facebook/sapling.git
synced 2024-10-10 16:57:49 +03:00
dfac9dda4a
Summary: This is part of "the great r-valuification of folly::Future": * This is something we should do for safety in general. * Several of folly::Future's methods are lvalue-qualified even though they act as though they are rvalue-qualified, that is, they provide a postcondition that says, in effect, callers should act as though the method invalidated its `this` object (regardless of whether that invalidation was actual or logical). * This violates the C++ principle to "Express ideas directly in code" (see Core Guidelines), and generally makes it more confusing for callers as well as hiding the actual semantics from tools (linters, compilers, etc.). * This dichotomy and confusion has manifested itself by some failures around D7840699 since lvalue-qualification hides that operation's move-out semantics - leads to some use of future operations that are really not correct, but are not obviously incorrect. * The goal of rvalueification is to make sure methods that are logically rvalue-qualified are actually rvalue-qualified, which forces callsites to acknowledge that rvalueification, e.g., `std::move(f).ensure(...)` instead of `f.ensure(...)`. This syntactic change in the callsites forces callers to acknowledge the method's rvalue semantics. This diff started as a Codemod, then required manual fixes. Here were the codemod steps: * expr.ensure(...) ==> std::move(expr).ensure(...) // if expr is not already an xvalue * expr->ensure(...) ==> std::move(*expr).ensure(...) Note: operator precedence of that last step is safe - no need to parenthesize `expr`. Reason: `->` binds more tightly than unary `*`. Reviewed By: yfeldblum Differential Revision: D9332070 fbshipit-source-id: 882121fe82c05fdb196ce676db686b6bc254974b |
||
|---|---|---|
| .. | ||
| config | ||
| fuse | ||
| inodes | ||
| journal | ||
| model | ||
| rocksdb | ||
| service | ||
| sqlite | ||
| store | ||
| takeover | ||
| testharness | ||
| utils | ||
| CMakeLists.txt | ||
| eden-config.h | ||