add switch_if_empty, default_if_empty

1 files changed, 154 insertions, 0 deletions

diff --git a/Rx/v2/test/operators/default_if_empty.cpp b/Rx/v2/test/operators/default_if_empty.cpp
new file mode 100644
index 0000000..048c8d5
--- /dev/null
+++ b/Rx/v2/test/operators/default_if_empty.cpp
@@ -0,0 +1,154 @@
+#include "../test.h"
+
+SCENARIO("default_if_empty should not switch if the source is not empty", "[default_if_empty][operators]"){
+    GIVEN("a source"){
+        auto sc = rxsc::make_test();
+        auto w = sc.create_worker();
+        const rxsc::test::messages<int> on;
+
+        auto xs = sc.make_hot_observable({
+            on.next(210, 1),
+            on.completed(250)
+        });
+
+        WHEN("started"){
+
+            auto res = w.start(
+                [xs]() {
+                    return xs.default_if_empty(2);
+                }
+            );
+
+            THEN("the output only contains an item from the source") {
+                auto required = rxu::to_vector({
+                    on.next(210, 1),
+                    on.completed(250)
+                });
+                auto actual = res.get_observer().messages();
+                REQUIRE(required == actual);
+            }
+
+            THEN("there was 1 subscription/unsubscription to the source"){
+                auto required = rxu::to_vector({
+                    on.subscribe(200, 250)
+                });
+                auto actual = xs.subscriptions();
+                REQUIRE(required == actual);
+            }
+        }
+    }
+}
+
+SCENARIO("default_if_empty should switch if the source is empty", "[default_if_empty][operators]"){
+    GIVEN("a source"){
+        auto sc = rxsc::make_test();
+        auto w = sc.create_worker();
+        const rxsc::test::messages<int> on;
+
+        auto xs = sc.make_hot_observable({
+            on.next(150, 1),
+            on.completed(250)
+        });
+
+        WHEN("started"){
+
+            auto res = w.start(
+                [xs]() {
+                    return xs.default_if_empty(2);
+                }
+            );
+
+            THEN("the output only contains an item from the backup source") {
+                auto required = rxu::to_vector({
+                    on.next(250, 2),
+                    on.completed(250)
+                });
+                auto actual = res.get_observer().messages();
+                REQUIRE(required == actual);
+            }
+
+            THEN("there was 1 subscription/unsubscription to the source"){
+                auto required = rxu::to_vector({
+                    on.subscribe(200, 250)
+                });
+                auto actual = xs.subscriptions();
+                REQUIRE(required == actual);
+            }
+        }
+    }
+}
+
+SCENARIO("default_if_empty - never", "[default_if_empty][operators]"){
+    GIVEN("a source"){
+        auto sc = rxsc::make_test();
+        auto w = sc.create_worker();
+        const rxsc::test::messages<int> on;
+
+        auto xs = sc.make_hot_observable({
+            on.next(150, 1)
+        });
+
+        WHEN("started"){
+
+            auto res = w.start(
+                [xs]() {
+                    return xs.default_if_empty(2);
+                }
+            );
+
+            THEN("the output is empty"){
+                auto required = std::vector<rxsc::test::messages<int>::recorded_type>();
+                auto actual = res.get_observer().messages();
+                REQUIRE(required == actual);
+            }
+
+            THEN("there was 1 subscription/unsubscription to the source"){
+                auto required = rxu::to_vector({
+                    on.subscribe(200, 1000)
+                });
+                auto actual = xs.subscriptions();
+                REQUIRE(required == actual);
+            }
+        }
+    }
+}
+
+SCENARIO("default_if_empty - source throws", "[default_if_empty][operators]"){
+    GIVEN("a source"){
+        auto sc = rxsc::make_test();
+        auto w = sc.create_worker();
+        const rxsc::test::messages<int> on;
+
+        std::runtime_error ex("default_if_empty on_error from source");
+
+        auto xs = sc.make_hot_observable({
+            on.next(150, 1),
+            on.error(250, ex)
+        });
+
+        WHEN("started"){
+
+            auto res = w.start(
+                [xs]() {
+                    return xs.default_if_empty(2);
+                }
+            );
+
+            THEN("the output only contains an error from the source"){
+                auto required = rxu::to_vector({
+                    on.error(250, ex)
+                });
+                auto actual = res.get_observer().messages();
+                REQUIRE(required == actual);
+            }
+
+            THEN("there was 1 subscription/unsubscription to the source"){
+                auto required = rxu::to_vector({
+                    on.subscribe(200, 250)
+                });
+                auto actual = xs.subscriptions();
+                REQUIRE(required == actual);
+            }
+        }
+    }
+}