Export of internal Abseil changes

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7f6c15aadc4d97e217dd446518dbb4fdc86b36a3 by Derek Mauro <dmauro@google.com>:

Upgrade GCC automated testing to use GCC 9.2 and Cmake 3.16.2

PiperOrigin-RevId: 288488783

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a978cee848d3cf65b0826c981bfd81022fc36660 by Abseil Team <absl-team@google.com>:

Removing formatting traits that were only used internally. ON_CALL/EXPECT_CALL do a sufficient job here.

PiperOrigin-RevId: 288386509

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fdec6f40293d5883220f1f0ea1261f7c5b60a66e by Derek Mauro <dmauro@google.com>:

Upgrade MacOS tests to use Bazel 2.0.0

PiperOrigin-RevId: 288373298

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465865c4123e9481ab50ea0527e92b39519704dd by Derek Mauro <dmauro@google.com>:

Changes to support GCC 9
 * Fix several -Wredundant-move warnings
 * Remove FlatHashMap.Any test, which basically doesn't work on any platform
   any more (see https://cplusplus.github.io/LWG/lwg-active.html#3121)
 * Fix a constant sign-compare warning
 * Conditionally compile out the PoisonHash test which doesn't build

PiperOrigin-RevId: 288360204

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57c4bb07fc58e7dd2a04f3c45027aab5ecaccf25 by Andy Soffer <asoffer@google.com>:

Deflaking MockingBitGen test. Because MockingBitGen can return random values,
it is inherently flaky. For log-unifrom, 2040 is a common enough value that
tests failed unreasonably frequently. Replacing it with a significantly larger
value so as to be much less common. 50000 is a good choice because it is (tied for) the least likely to occur randomly from this distribution, but is still in the distribution.

PiperOrigin-RevId: 288360112

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86f38e4109899d972de353b1c556c018cfe37956 by Matt Calabrese <calabrese@google.com>:

Remove construction tests for the internal `CompressedTuple<std::any>` instantiation. This was not guaranteed to work for the reasons that `std::tuple<std::any>` copy construction does not actually work by standard specification (some implementations introduce workarounds for this). In GCC9, `CompressedTuple<std::any>` and `std::tuple<std::any>` both fail for the same reasons, and a proper "fix" requires updating `std::any`, which is out of our control.

PiperOrigin-RevId: 288351977
GitOrigin-RevId: 7f6c15aadc4d97e217dd446518dbb4fdc86b36a3
Change-Id: I5d5c62bd297dc0ff1f2970ff076bb5cd088a7e4c

3 files changed, 57 insertions, 4 deletions

diff --git a/absl/random/internal/BUILD.bazel b/absl/random/internal/BUILD.bazel
index 8839078..d7ad4ef 100644
--- a/absl/random/internal/BUILD.bazel
+++ b/absl/random/internal/BUILD.bazel
@@ -509,6 +509,7 @@ cc_library(
     linkopts = ABSL_DEFAULT_LINKOPTS,
     deps = [
         "//absl/random",
+        "//absl/strings",
     ],
 )
 
diff --git a/absl/random/internal/distribution_caller.h b/absl/random/internal/distribution_caller.h
index ae2680d..02603cf 100644
--- a/absl/random/internal/distribution_caller.h
+++ b/absl/random/internal/distribution_caller.h
@@ -31,8 +31,22 @@ namespace random_internal {
 template <typename URBG>
 struct DistributionCaller {
   // Call the provided distribution type. The parameters are expected
-  // to be explicitly specified.  DistrT is the distribution type.
-  template <typename DistrT, typename... Args>
+  // to be explicitly specified.
+  // DistrT is the distribution type.
+  // FormatT is the formatter type:
+  //
+  // struct FormatT {
+  //   using result_type = distribution_t::result_type;
+  //   static std::string FormatCall(
+  //       const distribution_t& distr,
+  //       absl::Span<const result_type>);
+  //
+  //   static std::string FormatExpectation(
+  //       absl::string_view match_args,
+  //       absl::Span<const result_t> results);
+  // }
+  //
+  template <typename DistrT, typename FormatT, typename... Args>
   static typename DistrT::result_type Call(URBG* urbg, Args&&... args) {
     DistrT dist(std::forward<Args>(args)...);
     return dist(*urbg);
diff --git a/absl/random/internal/mocking_bit_gen_base.h b/absl/random/internal/mocking_bit_gen_base.h
index acd6387..eeeae9d 100644
--- a/absl/random/internal/mocking_bit_gen_base.h
+++ b/absl/random/internal/mocking_bit_gen_base.h
@@ -16,14 +16,39 @@
 #ifndef ABSL_RANDOM_INTERNAL_MOCKING_BIT_GEN_BASE_H_
 #define ABSL_RANDOM_INTERNAL_MOCKING_BIT_GEN_BASE_H_
 
+#include <atomic>
+#include <deque>
+#include <string>
 #include <typeinfo>
 
 #include "absl/random/random.h"
+#include "absl/strings/str_cat.h"
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
+// MockingBitGenExpectationFormatter is invoked to format unsatisfied mocks
+// and remaining results into a description string.
+template <typename DistrT, typename FormatT>
+struct MockingBitGenExpectationFormatter {
+  std::string operator()(absl::string_view args) {
+    return absl::StrCat(FormatT::FunctionName(), "(", args, ")");
+  }
+};
+
+// MockingBitGenCallFormatter is invoked to format each distribution call
+// into a description string for the mock log.
+template <typename DistrT, typename FormatT>
+struct MockingBitGenCallFormatter {
+  std::string operator()(const DistrT& dist,
+                         const typename DistrT::result_type& result) {
+    return absl::StrCat(
+        FormatT::FunctionName(), "(", FormatT::FormatArgs(dist), ") => {",
+        FormatT::FormatResults(absl::MakeSpan(&result, 1)), "}");
+  }
+};
+
 class MockingBitGenBase {
   template <typename>
   friend struct DistributionCaller;
@@ -36,9 +61,14 @@ class MockingBitGenBase {
   static constexpr result_type(max)() { return (generator_type::max)(); }
   result_type operator()() { return gen_(); }
 
+  MockingBitGenBase() : gen_(), observed_call_log_() {}
   virtual ~MockingBitGenBase() = default;
 
  protected:
+  const std::deque<std::string>& observed_call_log() {
+    return observed_call_log_;
+  }
+
   // CallImpl is the type-erased virtual dispatch.
   // The type of dist is always distribution<T>,
   // The type of result is always distribution<T>::result_type.
@@ -51,9 +81,10 @@ class MockingBitGenBase {
   }
 
   // Call the generating distribution function.
-  // Invoked by DistributionCaller<>::Call<DistT>.
+  // Invoked by DistributionCaller<>::Call<DistT, FormatT>.
   // DistT is the distribution type.
-  template <typename DistrT, typename... Args>
+  // FormatT is the distribution formatter traits type.
+  template <typename DistrT, typename FormatT, typename... Args>
   typename DistrT::result_type Call(Args&&... args) {
     using distr_result_type = typename DistrT::result_type;
     using ArgTupleT = std::tuple<absl::decay_t<Args>...>;
@@ -68,11 +99,18 @@ class MockingBitGenBase {
     if (!found_match) {
       result = dist(gen_);
     }
+
+    // TODO(asoffer): Forwarding the args through means we no longer need to
+    // extract them from the from the distribution in formatter traits. We can
+    // just StrJoin them.
+    observed_call_log_.push_back(
+        MockingBitGenCallFormatter<DistrT, FormatT>{}(dist, result));
     return result;
   }
 
  private:
   generator_type gen_;
+  std::deque<std::string> observed_call_log_;
 };  // namespace random_internal
 
 }  // namespace random_internal