From abc99a87a28be5a6699e9544f24e3f54005e6600 Mon Sep 17 00:00:00 2001
From: Corentin B <32176761+CorentinBT@users.noreply.github.com>
Date: Tue, 30 Apr 2024 22:29:53 +0200
Subject: [PATCH] Expose observable strategy_type (#567)

* Expose observable strategy_type

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Aleksey Loginov <victimsnino@gmail.com>
---
 src/rpp/rpp/observables.hpp            |  1 +
 src/rpp/rpp/observables/observable.hpp |  3 ++-
 src/tests/rpp/test_observables.cpp     | 21 +++++++++++++++++++++
 3 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/src/rpp/rpp/observables.hpp b/src/rpp/rpp/observables.hpp
index 301821257..279cb5d45 100644
--- a/src/rpp/rpp/observables.hpp
+++ b/src/rpp/rpp/observables.hpp
@@ -23,4 +23,5 @@
 #include <rpp/observables/blocking_observable.hpp>
 #include <rpp/observables/connectable_observable.hpp>
 #include <rpp/observables/dynamic_observable.hpp>
+#include <rpp/observables/grouped_observable.hpp>
 #include <rpp/observables/observable.hpp>
diff --git a/src/rpp/rpp/observables/observable.hpp b/src/rpp/rpp/observables/observable.hpp
index 42b0d9d78..20b373fc1 100644
--- a/src/rpp/rpp/observables/observable.hpp
+++ b/src/rpp/rpp/observables/observable.hpp
@@ -37,7 +37,8 @@ namespace rpp
     class observable
     {
     public:
-        using value_type = Type;
+        using value_type    = Type;
+        using strategy_type = Strategy;
 
         using expected_disposable_strategy = rpp::details::observables::deduce_disposable_strategy_t<Strategy>;
 
diff --git a/src/tests/rpp/test_observables.cpp b/src/tests/rpp/test_observables.cpp
index 6cf1b8bb2..349747ecb 100644
--- a/src/tests/rpp/test_observables.cpp
+++ b/src/tests/rpp/test_observables.cpp
@@ -16,6 +16,7 @@
 #include <rpp/sources/empty.hpp>
 #include <rpp/sources/error.hpp>
 #include <rpp/sources/never.hpp>
+#include <rpp/subjects/replay_subject.hpp>
 
 #include "rpp/disposables/fwd.hpp"
 #include "rpp/operators/fwd.hpp"
@@ -241,3 +242,23 @@ TEST_CASE("create observable works properly as observable")
         CHECK(pipe_operator_observer.get_on_completed_count() == pipe_function_observer.get_on_completed_count());
     }
 }
+
+TEMPLATE_TEST_CASE(
+    "observable has type traits defined",
+    "",
+    rpp::empty_observable<int>,
+    rpp::dynamic_observable<int>,
+    rpp::blocking_observable<int, rpp::details::empty_strategy<int>>,
+    rpp::connectable_observable<rpp::empty_observable<int>, rpp::subjects::replay_subject<int>>,
+    rpp::grouped_observable<int, int, rpp::details::empty_strategy<int>>)
+{
+    SECTION("value_type defined")
+    {
+        CONSTEVAL_CHECK(requires { typename TestType::value_type; });
+        CONSTEVAL_CHECK(std::is_same_v<typename TestType::value_type, int>);
+    }
+    SECTION("strategy_type defined")
+    {
+        CONSTEVAL_CHECK(requires { typename TestType::strategy_type; });
+    }
+}