Cleanup internal includes by splitting out some event structs

* Split out BenchmarkInfo and BenchmarkStats to their own header
* Outline BenchmarkStats<> declaration to separate header
* Split out TestRunInfo into its own header

These changes let us remove the large `interfaces_reporter.hpp`
include from `benchmark.hpp`, and replace it with
`interfaces_capture.hpp` in `run_context.hpp`.

I also cleaned out `interfaces_repoter.hpp` from reporter headers
that depend on `reporter_common_base.hpp`. This will not change
anything in the actual inclusion set, but makes it logically
more consistent.

16 files changed, 128 insertions, 56 deletions

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index e70ae580..1e0a09f1 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -21,6 +21,8 @@ set(BENCHMARK_HEADERS
   ${SOURCES_DIR}/benchmark/catch_sample_analysis.hpp
   ${SOURCES_DIR}/benchmark/detail/catch_analyse.hpp
   ${SOURCES_DIR}/benchmark/detail/catch_benchmark_function.hpp
+  ${SOURCES_DIR}/benchmark/detail/catch_benchmark_stats.hpp
+  ${SOURCES_DIR}/benchmark/detail/catch_benchmark_stats_fwd.hpp
   ${SOURCES_DIR}/benchmark/detail/catch_complete_invoke.hpp
   ${SOURCES_DIR}/benchmark/detail/catch_estimate_clock.hpp
   ${SOURCES_DIR}/benchmark/detail/catch_measure.hpp
@@ -128,6 +130,7 @@ set(IMPL_HEADERS
   ${SOURCES_DIR}/internal/catch_test_failure_exception.hpp
   ${SOURCES_DIR}/internal/catch_test_macro_impl.hpp
   ${SOURCES_DIR}/internal/catch_test_registry.hpp
+  ${SOURCES_DIR}/internal/catch_test_run_info.hpp
   ${SOURCES_DIR}/internal/catch_test_spec_parser.hpp
   ${SOURCES_DIR}/internal/catch_textflow.hpp
   ${SOURCES_DIR}/internal/catch_to_string.hpp
diff --git a/src/catch2/benchmark/catch_benchmark.hpp b/src/catch2/benchmark/catch_benchmark.hpp
index 57adc67a..3623133d 100644
--- a/src/catch2/benchmark/catch_benchmark.hpp
+++ b/src/catch2/benchmark/catch_benchmark.hpp
@@ -19,7 +19,7 @@
 #include <catch2/interfaces/catch_interfaces_capture.hpp>
 #include <catch2/interfaces/catch_interfaces_config.hpp>
 #include <catch2/interfaces/catch_interfaces_registry_hub.hpp>
-#include <catch2/interfaces/catch_interfaces_reporter.hpp>
+#include <catch2/benchmark/detail/catch_benchmark_stats.hpp>
 #include <catch2/benchmark/catch_clock.hpp>
 #include <catch2/benchmark/catch_environment.hpp>
 #include <catch2/benchmark/catch_execution_plan.hpp>
diff --git a/src/catch2/benchmark/catch_benchmark_all.hpp b/src/catch2/benchmark/catch_benchmark_all.hpp
index eb81f238..56fc7c74 100644
--- a/src/catch2/benchmark/catch_benchmark_all.hpp
+++ b/src/catch2/benchmark/catch_benchmark_all.hpp
@@ -33,6 +33,8 @@
 #include <catch2/benchmark/catch_sample_analysis.hpp>
 #include <catch2/benchmark/detail/catch_analyse.hpp>
 #include <catch2/benchmark/detail/catch_benchmark_function.hpp>
+#include <catch2/benchmark/detail/catch_benchmark_stats.hpp>
+#include <catch2/benchmark/detail/catch_benchmark_stats_fwd.hpp>
 #include <catch2/benchmark/detail/catch_complete_invoke.hpp>
 #include <catch2/benchmark/detail/catch_estimate_clock.hpp>
 #include <catch2/benchmark/detail/catch_measure.hpp>
diff --git a/src/catch2/benchmark/detail/catch_benchmark_stats.hpp b/src/catch2/benchmark/detail/catch_benchmark_stats.hpp
new file mode 100644
index 00000000..a8b3494e
--- /dev/null
+++ b/src/catch2/benchmark/detail/catch_benchmark_stats.hpp
@@ -0,0 +1,64 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+#ifndef CATCH_BENCHMARK_STATS_HPP_INCLUDED
+#define CATCH_BENCHMARK_STATS_HPP_INCLUDED
+
+#include <catch2/internal/catch_move_and_forward.hpp>
+#include <catch2/benchmark/catch_estimate.hpp>
+#include <catch2/benchmark/catch_outlier_classification.hpp>
+// The fwd decl & default specialization needs to be seen by VS2017 before
+// BenchmarkStats itself, or VS2017 will report compilation error.
+#include <catch2/benchmark/detail/catch_benchmark_stats_fwd.hpp>
+
+#include <string>
+#include <vector>
+
+namespace Catch {
+
+    struct BenchmarkInfo {
+        std::string name;
+        double estimatedDuration;
+        int iterations;
+        unsigned int samples;
+        unsigned int resamples;
+        double clockResolution;
+        double clockCost;
+    };
+
+    template <class Duration>
+    struct BenchmarkStats {
+        BenchmarkInfo info;
+
+        std::vector<Duration> samples;
+        Benchmark::Estimate<Duration> mean;
+        Benchmark::Estimate<Duration> standardDeviation;
+        Benchmark::OutlierClassification outliers;
+        double outlierVariance;
+
+        template <typename Duration2>
+        operator BenchmarkStats<Duration2>() const {
+            std::vector<Duration2> samples2;
+            samples2.reserve(samples.size());
+            for (auto const& sample : samples) {
+                samples2.push_back(Duration2(sample));
+            }
+            return {
+                info,
+                CATCH_MOVE(samples2),
+                mean,
+                standardDeviation,
+                outliers,
+                outlierVariance,
+            };
+        }
+    };
+
+
+} // end namespace Catch
+
+#endif // CATCH_BENCHMARK_STATS_HPP_INCLUDED
diff --git a/src/catch2/benchmark/detail/catch_benchmark_stats_fwd.hpp b/src/catch2/benchmark/detail/catch_benchmark_stats_fwd.hpp
new file mode 100644
index 00000000..60772561
--- /dev/null
+++ b/src/catch2/benchmark/detail/catch_benchmark_stats_fwd.hpp
@@ -0,0 +1,23 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+#ifndef CATCH_BENCHMARK_STATS_FWD_HPP_INCLUDED
+#define CATCH_BENCHMARK_STATS_FWD_HPP_INCLUDED
+
+#include <chrono>
+
+namespace Catch {
+
+    // We cannot forward declare the type with default template argument
+    // multiple times, so it is split out into a separate header so that
+    // we can prevent multiple declarations in dependees
+    template <typename Duration = std::chrono::duration<double, std::nano>>
+    struct BenchmarkStats;
+
+} // end namespace Catch
+
+#endif // CATCH_BENCHMARK_STATS_FWD_HPP_INCLUDED
diff --git a/src/catch2/catch_all.hpp b/src/catch2/catch_all.hpp
index be146421..9b2cbe20 100644
--- a/src/catch2/catch_all.hpp
+++ b/src/catch2/catch_all.hpp
@@ -111,6 +111,7 @@
 #include <catch2/internal/catch_test_failure_exception.hpp>
 #include <catch2/internal/catch_test_macro_impl.hpp>
 #include <catch2/internal/catch_test_registry.hpp>
+#include <catch2/internal/catch_test_run_info.hpp>
 #include <catch2/internal/catch_test_spec_parser.hpp>
 #include <catch2/internal/catch_textflow.hpp>
 #include <catch2/internal/catch_to_string.hpp>
diff --git a/src/catch2/catch_session.cpp b/src/catch2/catch_session.cpp
index 259026d0..af817017 100644
--- a/src/catch2/catch_session.cpp
+++ b/src/catch2/catch_session.cpp
@@ -14,7 +14,6 @@
 #include <catch2/catch_test_spec.hpp>
 #include <catch2/catch_version.hpp>
 #include <catch2/interfaces/catch_interfaces_testcase.hpp>
-#include <catch2/interfaces/catch_interfaces_reporter.hpp>
 #include <catch2/internal/catch_startup_exception_registry.hpp>
 #include <catch2/internal/catch_sharding.hpp>
 #include <catch2/internal/catch_textflow.hpp>
diff --git a/src/catch2/interfaces/catch_interfaces_capture.hpp b/src/catch2/interfaces/catch_interfaces_capture.hpp
index c3c80d75..e605f998 100644
--- a/src/catch2/interfaces/catch_interfaces_capture.hpp
+++ b/src/catch2/interfaces/catch_interfaces_capture.hpp
@@ -14,6 +14,7 @@
 #include <catch2/internal/catch_stringref.hpp>
 #include <catch2/internal/catch_result_type.hpp>
 #include <catch2/internal/catch_unique_ptr.hpp>
+#include <catch2/benchmark/detail/catch_benchmark_stats_fwd.hpp>
 
 namespace Catch {
 
@@ -31,8 +32,6 @@ namespace Catch {
     class IGeneratorTracker;
 
     struct BenchmarkInfo;
-    template <typename Duration = std::chrono::duration<double, std::nano>>
-    struct BenchmarkStats;
 
     namespace Generators {
         class GeneratorUntypedBase;
diff --git a/src/catch2/interfaces/catch_interfaces_reporter.hpp b/src/catch2/interfaces/catch_interfaces_reporter.hpp
index 8ebc7a73..0ce62e86 100644
--- a/src/catch2/interfaces/catch_interfaces_reporter.hpp
+++ b/src/catch2/interfaces/catch_interfaces_reporter.hpp
@@ -13,11 +13,10 @@
 #include <catch2/catch_assertion_result.hpp>
 #include <catch2/internal/catch_message_info.hpp>
 #include <catch2/internal/catch_stringref.hpp>
+#include <catch2/internal/catch_test_run_info.hpp>
 #include <catch2/internal/catch_unique_ptr.hpp>
 #include <catch2/internal/catch_move_and_forward.hpp>
-#include <catch2/benchmark/catch_estimate.hpp>
-#include <catch2/benchmark/catch_outlier_classification.hpp>
-#include <catch2/interfaces/catch_interfaces_capture.hpp>
+#include <catch2/benchmark/detail/catch_benchmark_stats.hpp>
 
 #include <map>
 #include <string>
@@ -57,11 +56,6 @@ namespace Catch {
         std::map<std::string, std::string> m_customOptions;
     };
 
-    struct TestRunInfo {
-        constexpr TestRunInfo(StringRef _name) : name(_name) {}
-        StringRef name;
-    };
-
     struct AssertionStats {
         AssertionStats( AssertionResult const& _assertionResult,
                         std::vector<MessageInfo> const& _infoMessages,
@@ -113,45 +107,6 @@ namespace Catch {
         bool aborting;
     };
 
-
-    struct BenchmarkInfo {
-        std::string name;
-        double estimatedDuration;
-        int iterations;
-        unsigned int samples;
-        unsigned int resamples;
-        double clockResolution;
-        double clockCost;
-    };
-
-    template <class Duration>
-    struct BenchmarkStats {
-        BenchmarkInfo info;
-
-        std::vector<Duration> samples;
-        Benchmark::Estimate<Duration> mean;
-        Benchmark::Estimate<Duration> standardDeviation;
-        Benchmark::OutlierClassification outliers;
-        double outlierVariance;
-
-        template <typename Duration2>
-        operator BenchmarkStats<Duration2>() const {
-            std::vector<Duration2> samples2;
-            samples2.reserve(samples.size());
-            for (auto const& sample : samples) {
-                samples2.push_back(Duration2(sample));
-            }
-            return {
-                info,
-                CATCH_MOVE(samples2),
-                mean,
-                standardDeviation,
-                outliers,
-                outlierVariance,
-            };
-        }
-    };
-
     //! By setting up its preferences, a reporter can modify Catch2's behaviour
     //! in some regards, e.g. it can request Catch2 to capture writes to
     //! stdout/stderr during test execution, and pass them to the reporter.
diff --git a/src/catch2/internal/catch_run_context.cpp b/src/catch2/internal/catch_run_context.cpp
index 11fcda45..6fd63450 100644
--- a/src/catch2/internal/catch_run_context.cpp
+++ b/src/catch2/internal/catch_run_context.cpp
@@ -8,8 +8,9 @@
 #include <catch2/internal/catch_run_context.hpp>
 
 #include <catch2/catch_user_config.hpp>
-#include <catch2/interfaces/catch_interfaces_generatortracker.hpp>
 #include <catch2/interfaces/catch_interfaces_config.hpp>
+#include <catch2/interfaces/catch_interfaces_generatortracker.hpp>
+#include <catch2/interfaces/catch_interfaces_reporter.hpp>
 #include <catch2/internal/catch_compiler_capabilities.hpp>
 #include <catch2/internal/catch_context.hpp>
 #include <catch2/internal/catch_enforce.hpp>
diff --git a/src/catch2/internal/catch_run_context.hpp b/src/catch2/internal/catch_run_context.hpp
index de6999e5..fc65f651 100644
--- a/src/catch2/internal/catch_run_context.hpp
+++ b/src/catch2/internal/catch_run_context.hpp
@@ -8,8 +8,9 @@
 #ifndef CATCH_RUN_CONTEXT_HPP_INCLUDED
 #define CATCH_RUN_CONTEXT_HPP_INCLUDED
 
-#include <catch2/interfaces/catch_interfaces_reporter.hpp>
+#include <catch2/interfaces/catch_interfaces_capture.hpp>
 #include <catch2/internal/catch_test_registry.hpp>
+#include <catch2/internal/catch_test_run_info.hpp>
 #include <catch2/internal/catch_fatal_condition_handler.hpp>
 #include <catch2/catch_test_case_info.hpp>
 #include <catch2/catch_message.hpp>
@@ -26,6 +27,8 @@ namespace Catch {
 
     class IGeneratorTracker;
     class IConfig;
+    class IEventListener;
+    using IEventListenerPtr = Detail::unique_ptr<IEventListener>;
 
     ///////////////////////////////////////////////////////////////////////////
 
diff --git a/src/catch2/internal/catch_test_run_info.hpp b/src/catch2/internal/catch_test_run_info.hpp
new file mode 100644
index 00000000..90357b0a
--- /dev/null
+++ b/src/catch2/internal/catch_test_run_info.hpp
@@ -0,0 +1,22 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+#ifndef CATCH_TEST_RUN_INFO_HPP_INCLUDED
+#define CATCH_TEST_RUN_INFO_HPP_INCLUDED
+
+#include <catch2/internal/catch_stringref.hpp>
+
+namespace Catch {
+
+    struct TestRunInfo {
+        constexpr TestRunInfo(StringRef _name) : name(_name) {}
+        StringRef name;
+    };
+
+} // end namespace Catch
+
+#endif // CATCH_TEST_RUN_INFO_HPP_INCLUDED
diff --git a/src/catch2/meson.build b/src/catch2/meson.build
index 789d847d..6aa1d9e1 100644
--- a/src/catch2/meson.build
+++ b/src/catch2/meson.build
@@ -32,6 +32,8 @@ benchmark_headers = [
   'benchmark/catch_sample_analysis.hpp',
   'benchmark/detail/catch_analyse.hpp',
   'benchmark/detail/catch_benchmark_function.hpp',
+  'benchmark/detail/catch_benchmark_stats.hpp',
+  'benchmark/detail/catch_benchmark_stats_fwd.hpp',
   'benchmark/detail/catch_complete_invoke.hpp',
   'benchmark/detail/catch_estimate_clock.hpp',
   'benchmark/detail/catch_measure.hpp',
@@ -133,6 +135,7 @@ internal_headers = [
   'internal/catch_test_failure_exception.hpp',
   'internal/catch_test_macro_impl.hpp',
   'internal/catch_test_registry.hpp',
+  'internal/catch_test_run_info.hpp',
   'internal/catch_test_spec_parser.hpp',
   'internal/catch_textflow.hpp',
   'internal/catch_to_string.hpp',
diff --git a/src/catch2/reporters/catch_reporter_automake.hpp b/src/catch2/reporters/catch_reporter_automake.hpp
index 3475a1fd..a639428c 100644
--- a/src/catch2/reporters/catch_reporter_automake.hpp
+++ b/src/catch2/reporters/catch_reporter_automake.hpp
@@ -8,7 +8,6 @@
 #ifndef CATCH_REPORTER_AUTOMAKE_HPP_INCLUDED
 #define CATCH_REPORTER_AUTOMAKE_HPP_INCLUDED
 
-#include <catch2/interfaces/catch_interfaces_reporter.hpp>
 #include <catch2/reporters/catch_reporter_streaming_base.hpp>
 #include <catch2/internal/catch_move_and_forward.hpp>
 
diff --git a/src/catch2/reporters/catch_reporter_cumulative_base.hpp b/src/catch2/reporters/catch_reporter_cumulative_base.hpp
index cdff9991..691e1f95 100644
--- a/src/catch2/reporters/catch_reporter_cumulative_base.hpp
+++ b/src/catch2/reporters/catch_reporter_cumulative_base.hpp
@@ -8,7 +8,6 @@
 #ifndef CATCH_REPORTER_CUMULATIVE_BASE_HPP_INCLUDED
 #define CATCH_REPORTER_CUMULATIVE_BASE_HPP_INCLUDED
 
-#include <catch2/interfaces/catch_interfaces_reporter.hpp>
 #include <catch2/reporters/catch_reporter_common_base.hpp>
 #include <catch2/internal/catch_move_and_forward.hpp>
 #include <catch2/internal/catch_unique_ptr.hpp>
diff --git a/src/catch2/reporters/catch_reporter_streaming_base.hpp b/src/catch2/reporters/catch_reporter_streaming_base.hpp
index 13672a28..5448000c 100644
--- a/src/catch2/reporters/catch_reporter_streaming_base.hpp
+++ b/src/catch2/reporters/catch_reporter_streaming_base.hpp
@@ -8,7 +8,6 @@
 #ifndef CATCH_REPORTER_STREAMING_BASE_HPP_INCLUDED
 #define CATCH_REPORTER_STREAMING_BASE_HPP_INCLUDED
 
-#include <catch2/interfaces/catch_interfaces_reporter.hpp>
 #include <catch2/reporters/catch_reporter_common_base.hpp>
 #include <catch2/internal/catch_move_and_forward.hpp>