Summary: Given a cpp folly::coro::AsyncGenerator, a python async generator/iterator may be built and bridged to it. Users may use `async for ...` syntax to consume data from it.

Reviewed By: yfeldblum

Differential Revision: D16404979

fbshipit-source-id: dd2dfd52d00bd1a3e30e838359a27458744f6461

Summary:
Some people want to use getdeps with Python 2.7. This looks easy to do, so take a step toward Python 2.7 support by fixing getdeps' tests when run with Python 2.7.

For Python 3, this diff should not change behavior.

This diff should address https://github.com/facebook/bistro/issues/35.

Reviewed By: snarkmaster

Differential Revision: D16435667

fbshipit-source-id: f5c262b12995b609263341c4de26dac7f9b12b70

Summary:
This is just https://github.com/facebook/bistro/pull/37/, backported to `fbcode_builder`.

snarkmaster
Pull Request resolved: https://github.com/facebook/bistro/pull/37

Test Plan: Push and watch Travis

Reviewed By: simpkins

Differential Revision: D16453080

Pulled By: snarkmaster

fbshipit-source-id: a15eaead931f046c41e50f8e3b412ef68b172d65

Summary:
`dynamic::hash()` would copy every key-value pair in the object accumulator hash because of two bugs in the code:
1. The lambda took `auto` instead of `auto const&`
2. The hasher was `hash<pair<dynamic, dynamic>>` not `hash<pair<dynamic const, dynamic>>` meaning a conversion was needed.

These bugs together caused 2 copies for each sub-object. Since the copies are recursive, each object got copied 2*depth times.

Reviewed By: yfeldblum

Differential Revision: D16452213

fbshipit-source-id: 64a55e1640abb022c148183646e9f9720fd8482e

Summary:
This is a proposed fix for issue: https://github.com/facebook/folly/issues/1193
Using `folly::resizeWithoutInitialization` with libc++ and the address sanitizer causes false positive 'container overflow' failures.

This PR only addresses the problem for resizing `std::vector`. Presumably the version of `folly::resizeWithoutInitialization` for `std::string` has the same problem, but I have not verified this.

### Potential issues
This PR assumes that the `__sanitizer_annotate_contiguous_container` is available in libc++, and that the `std::vector` implementation has been annotated with it. The latter occurred in ~2014:
http://llvm.org/viewvc/llvm-project/libcxx/trunk/include/vector?r1=191987&r2=208319&pathrev=208319

If there are people using C++14 compilers with versions of libc++ predating the addition of the `std::vector<T>::__annotate_contiguous_container` member function then this fix will fail to compile.

I'm not aware of any sane way to detect the exact version of libc++ being used. Perhaps a suitable mitigation for those (few?) people with a C++14 compiler and pre-2015 libc++ implementation would be to provide a `FOLLY_` macro to disable the annotation.
Pull Request resolved: https://github.com/facebook/folly/pull/1194

Reviewed By: yfeldblum

Differential Revision: D16445890

Pulled By: nbronson

fbshipit-source-id: ef33bbd5cc12c71822985c5174bf8e47e6eb3757

Summary: [Folly] Extract type aliases in `LtHash` members to avoid unnatural line breaks and indentation.

Reviewed By: modocache

Differential Revision: D16453375

fbshipit-source-id: 8d68458ba3ba7bf79fef82986f4f170e3b74ddd6

Summary: [Folly] Apply `clang-format` to `folly/experimental/crypto/`.

Reviewed By: modocache

Differential Revision: D16453122

fbshipit-source-id: 5a24b20dba3ab472cd490afaaa24e7ab1c1295ec

Summary:
getdeps allowed common arguments to be specified either before or after
the subcommand name.  However, the arguments were only actually honored
if they were specified on the command line after the subcommand name.
Specifying any of these arguments before the subcommand would simply be
ignored, and the default value would be used.  This happened since the
subcommand argument's default value overwrote the value specified by the
user from the main command parser.

This fixes the behavior by using `argparse.SUPPRESS` so that argparse
won't set the value at all if it was not specified.  This allows the
value from the main parser to be used correctly if the argument was not
seen by the subcommand parser.

Reviewed By: chadaustin

Differential Revision: D16435358

fbshipit-source-id: f3893ef7a27fb018247f249f313d6438472e0140

Summary: F14NodeSet::insert() leaks memory when construction throws.

Reviewed By: yfeldblum, nbronson

Differential Revision: D16399317

fbshipit-source-id: 4c9385288dd212469dfbd10b3e990b3533dc66d3

Summary: eachToTuple: use to<fbstring>(delim) instead of delim

Reviewed By: yfeldblum

Differential Revision: D16419866

fbshipit-source-id: 7a57f41ea210c569284f6c619784adc95f03b26e

Reviewed By: yfeldblum

Differential Revision: D16426555

fbshipit-source-id: 0211c58b6919dc412b9cd7a029f0543d0060b40b

Differential Revision: D16368120

fbshipit-source-id: 0511e2f84b3bf8d1affbfbeecd05c04cb0269037

Summary: This file is included in `coro/TimedWait.h` and `coro/Collect.h`, so inclusion of those two headers is causing redefinition errors.

Reviewed By: yfeldblum

Differential Revision: D16414841

fbshipit-source-id: 103fa87a7c978d256e58eb67089b4cb984d362e4

Summary:
The /EHa flag tells MSVC to catch asynchronous (structured) exceptions
in `catch(...)` blocks. This is generally a bad idea, because
structured exceptions include page faults, stack overflow, division by
zero, and illegal instructions, at which point attempting to run
further arbitrary C++ code will have wonky effects in the best
case. It would probably also clobber any state required to debug the
original failure.

Reviewed By: Orvid

Differential Revision: D16390933

fbshipit-source-id: 2997daaf350680dc9d0c7da3cabab8749e8ecb82

Summary:
The documentation claims that the constructor only throws
`std::invalid_argument`, but it could throw a `ConversionError`.

Reviewed By: Orvid

Differential Revision: D16387303

fbshipit-source-id: 887a84f48a49acdc0516605f8204432bfd8ca800

Summary: Cut remaining explicit class template instantiations in futures.

Reviewed By: mengz0

Differential Revision: D16366146

fbshipit-source-id: e755188bd4378ca713b2d73b74def76f9ad837a7

Summary: It doesn't have any thrift specific code. Moving it to folly allows other folly Cython code use cFollyOptional.

Reviewed By: fried

Differential Revision: D16388752

fbshipit-source-id: 459c564571ba01fb8f22996227120ba631ffc05c

Summary:
If `path_search()` returns that CMake is not available, raise an Exception and
fail the build.  This makes the failure somewhat easier to to identify.
Without this the code would continue and would try to invoke `subprocess` with
a value of `None` in the command argument list.  This error is slightly harder
to debug, since it isn't clear which command argument or environment variable
is not a string.

Reviewed By: chadaustin

Differential Revision: D16354623

fbshipit-source-id: be972b02cb13bc70db0f867da70e5bf4c6cec46d

Summary:
The scratch path is used as part of the hash computation for each project.  We
need to make sure this path is always normalized to ensure that we compute the
hashes consistently.

Reviewed By: chadaustin

Differential Revision: D16354624

fbshipit-source-id: 39b5362620bdc247cd7e7f1333dac319b354dc6f

Summary:
getdeps currently ends up calling `path_search()` repeatedly searching for
various C/C++ compilers in $PATH.  It ends up doing this multiple times for
each dependency as it computes the project hashes.  This updates the
`path_search()` function to cache its results so that we don't keep performing
the same searches on the file system over and over again.

Reviewed By: chadaustin

Differential Revision: D16354625

fbshipit-source-id: 116293bd2f636632517d26436b2332e6c10624f1

Summary: Fix mem leak due to observer not being freed

Reviewed By: yfeldblum

Differential Revision: D16234386

fbshipit-source-id: 54ea9e904cf6cde0e24edf1511c2e3b46a58376f

Summary: This particular `std::min` is ambiguous on macOS.

Reviewed By: simpkins

Differential Revision: D16352637

fbshipit-source-id: d444b4b5f22c94b76da5463493efe433829bbba5

Summary:
1. Py_INCREF when holding py future object in bridge function. Py_DECREF in a scope guard.
2. fix typo("folly::coroTask" should be "folly::coro::Task")

Reviewed By: yfeldblum, andriigrynenko

Differential Revision: D16341866

fbshipit-source-id: 1d5b946596cd86c4a949e2c66f007a6140046506

Summary: eden.thrift includes fb303_core.thrift, so any cmake target that depends on eden.thrift should pull in fb303_core.thrift's include directories and libraries. Implement that machinery in CppThriftLibrary.cmake.

Reviewed By: wez

Differential Revision: D16062657

fbshipit-source-id: d5d962960e767a138a9b634a12aebccf72d6ef43

Summary: Add a manifest and CMakeLists.txt for building fb303 with cmake.

Reviewed By: wez

Differential Revision: D15480895

fbshipit-source-id: d47f6ef9b9383b79b31a6170c7d4c9e8337de4d8

Summary:
Deprecate Future::then(executor, callback) pending removal.

This form of Future::then is ambiguous, and does not yet implement the stronger
typing of thenValue and thenTry. It is also tempting to use instead of via,
where it is not obvious that it has the behaviour of wrapping a via call in a
push and pop of the current executor:
.pushCurrentExecutor().via(executor).then(callback).popCurrentExecutor().

With the addition of inline continuations, we can instead make the nesting
explicit at low cost by making it an inline continuation that launches an
asynchronous task on the passed executor.

Reviewed By: yfeldblum

Differential Revision: D16282826

fbshipit-source-id: a94c994cf02f43f7a2bd857237885b25591fa9aa

Summary:
Fix an error about source directories being included in the include
path in add_thrift_cpp2_library. I don't know why this was failing for
fb303 and not for other projects, but adding a generation expression
appears to fix the issue.

Reviewed By: strager

Differential Revision: D15725024

fbshipit-source-id: 6c02fed6c6703733cf9e0b130c0f90b70e3ea300

Summary: Adds a callback interface to facilitate adding elision support for folly::Singleton. Planned to add context-aware elision support which will use an adaptation method based on the interface's callsite information (ie, the type of the Singleton instance, T, and the type of the callback function, F).

Reviewed By: nbronson

Differential Revision: D15970597

fbshipit-source-id: 1010322c64d1b7900b4bef5b35059238efabb071

Reviewed By: yfeldblum, luciang

Differential Revision: D16164723

fbshipit-source-id: ed0c4b2dddb09c8d97a8aca9379e4ea9b107a92c

Reviewed By: andriigrynenko

Differential Revision: D14637661

fbshipit-source-id: 0f8852e30ff554e9f0125e2d918054e4bc1e5af5

Reviewed By: yfeldblum

Differential Revision: D16214195

fbshipit-source-id: 4841b0ba3188f19aba7a0e2c2ffd04d2f5f55220

Summary:
TSAN: AtForkList::child() - ignore reads, writes and sync

(Note: this ignores all push blocking failures!)

Reviewed By: yfeldblum

Differential Revision: D16196384

fbshipit-source-id: 28ea3b9fdb317eaffcb428f6ae705d5c4e5de887

Summary:
Fix dyndeps.py to find dumpbin.exe in more situations.

Previously the code looked for dumpbin.exe under Visual Studio directories
named either `BuildTools` or `Community`.  On a system with an MSVC 2017
Professional install it is instead located under a directory named
`Professional`.  This updates the glob to allow any directory name here.

Reviewed By: pkaush

Differential Revision: D16207692

fbshipit-source-id: 1a57ec29653a89fd3e751b3e4408a298b4632b11

Summary:
We expose iobuf to Python via the folly.iobuf Python extension. The code for this extension has historically been in the fbthrift source tree. Move it to folly so that folly produces folly extensions and thrift produces thrift extensions.

Without this change we end up with the folly.iobuf Cython extension being packaged with thrift rather than folly, leading the need for a number of work-arounds to allow Python and Cython to find folly.iobuf without stopping their searches on folly.executor.

The tests for IOBuf python extension has been added to folly while maintaining the thrift-specific IOBuf tests in thrift.

Reviewed By: vitaut

Differential Revision: D14405645

fbshipit-source-id: 662a4e32c219f6d044bb6e903a2525ec1b4059c5

Summary: is_objfile() is used to find the executable files in the given project. Getdeps will only find and copy the dependencies of the binaries identified by this function. On Windows we will copy only the dependencies for an exe file.

Reviewed By: chadaustin

Differential Revision: D16185962

fbshipit-source-id: f6b5089401b242514a845e3a97b3804051d93c1c

Summary: Instead of using setCallbackAndDetach (which is hard to apply in all cases because of cancellation), this diff fixes releaseDefferedExecutor.

Reviewed By: yfeldblum

Differential Revision: D16189338

fbshipit-source-id: 47ef192dd0cec3c13824071c8ba7e1dd06968a70

Reviewed By: yfeldblum

Differential Revision: D15915100

fbshipit-source-id: afc131bdf143ac0eec15523e257545d63207cb34

Summary:
This are noisy and don't provide real value, so remove
the webhooks.

Reviewed By: yns88

Differential Revision: D16115486

fbshipit-source-id: 1daa2d78f4e786a42dcc5779ccd30c36e02d2445

Summary:
Some changes to get Poly compiling with VS2019 (and correcting an oversight from https://github.com/facebook/folly/pull/1174)

The change to `detail/TypeList.h` is straightforward I think.

The introduction of `getOpsImpl` I find a bit distasteful...I will remark that as of Visual Studio 16.2.0 Preview 3.0 it is not necessary, but it is still needed on Visual Studio 16.1.5 (latest release, non preview).

Orvid in your comment [here](https://github.com/facebook/folly/pull/1178#issuecomment-506864383)  you mentioned the question of supporting VS 2017 or VS 2019 given that Poly had no MSVC support at all beforehand. I re-downloaded VS 2017 on my machine to test against the fixes added here and the situation seemed discouraging with lots more errors and perhaps less obvious workarounds.

I have not made any changes to the CMake stuff for Poly on MSVC: https://github.com/facebook/folly/blob/master/CMakeLists.txt#L235

I'm not sure if once we resolve the issue above we might want to add some logic maybe [here](https://github.com/facebook/folly/blob/master/CMakeLists.txt#L63) to handle which version of MSVC is approved for poly; will wait for further direction on that.
Pull Request resolved: https://github.com/facebook/folly/pull/1182

Reviewed By: Orvid

Differential Revision: D16109504

Pulled By: yfeldblum

fbshipit-source-id: d20b242494b075ce91452215c2025584fe488d65

Summary:
Test AsyncSocketTest.getBufInUse was throwing exceptions, I believe
this should fix those issues. The problem appeared to be that the socket
connection did not always work immediately so we needed to call loop() on the
event base so that an async connection could complete.

Reviewed By: yfeldblum

Differential Revision: D16052111

fbshipit-source-id: 9793e613eea5b17cb3ab00605355102b2f8807d8