--list-* flags write to target specified by the -o flag

Also added tests for the default implementations of list* reporter
helpers.

Closes #2061

tests/SelfTest/IntrospectiveTests/Reporters.tests.cpp

@@ -0,0 +1,109 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE_1_0.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+
+#include <catch2/catch_test_macros.hpp>
+
+#include <catch2/catch_test_case_info.hpp>
+#include <catch2/catch_config.hpp>
+#include <catch2/interfaces/catch_interfaces_reporter.hpp>
+#include <catch2/interfaces/catch_interfaces_reporter_factory.hpp>
+#include <catch2/interfaces/catch_interfaces_reporter_registry.hpp>
+#include <catch2/internal/catch_list.hpp>
+#include <catch2/matchers/catch_matchers_string.hpp>
+#include <catch2/reporters/catch_reporter_helpers.hpp>
+
+#include <sstream>
+
+TEST_CASE( "The default listing implementation write to provided stream",
+           "[reporters][reporter-helpers]" ) {
+    using Catch::Matchers::Contains;
+    using namespace std::string_literals;
+
+    std::stringstream sstream;
+    SECTION( "Listing tags" ) {
+        std::vector<Catch::TagInfo> tags(1);
+        tags[0].add("fakeTag"_catch_sr);
+        Catch::defaultListTags(sstream, tags, false);
+
+        auto listingString = sstream.str();
+        REQUIRE_THAT(listingString, Contains("[fakeTag]"s));
+    }
+    SECTION( "Listing reporters" ) {
+        std::vector<Catch::ReporterDescription> reporters(
+            { { "fake reporter", "fake description" } } );
+        Catch::defaultListReporters(sstream, reporters, Catch::Verbosity::Normal);
+
+        auto listingString = sstream.str();
+        REQUIRE_THAT(listingString, Contains("fake reporter"s));
+    }
+    SECTION( "Listing tests" ) {
+        Catch::TestCaseInfo fakeInfo{
+            ""s,
+            { "fake test name"_catch_sr, "[fakeTestTag]"_catch_sr },
+            { "fake-file.cpp", 123456789 } };
+        std::vector<Catch::TestCaseHandle> tests({ {&fakeInfo, nullptr} });
+        Catch::defaultListTests(sstream, tests, false, Catch::Verbosity::Normal);
+
+        auto listingString = sstream.str();
+        REQUIRE_THAT( listingString,
+                      Contains( "fake test name"s ) &&
+                          Contains( "fakeTestTag"s ) );
+    }
+}
+
+TEST_CASE( "Reporter's write listings to provided stream", "[reporters]" ) {
+    using Catch::Matchers::Contains;
+    using namespace std::string_literals;
+
+    auto const& factories = Catch::getRegistryHub().getReporterRegistry().getFactories();
+    // If there are no reporters, the test would pass falsely
+    // while there is something obviously broken
+    REQUIRE_FALSE(factories.empty());
+
+    for (auto const& factory : factories) {
+        INFO("Tested reporter: " << factory.first);
+        std::stringstream sstream;
+
+        Catch::ConfigData config_data;
+        Catch::Config config( config_data );
+        Catch::ReporterConfig rep_config( &config, sstream );
+        auto reporter = factory.second->create( rep_config );
+
+        DYNAMIC_SECTION( factory.first << " reporter lists tags" ) {
+            std::vector<Catch::TagInfo> tags(1);
+            tags[0].add("fakeTag"_catch_sr);
+            reporter->listTags(tags);
+
+            auto listingString = sstream.str();
+            REQUIRE_THAT(listingString, Contains("fakeTag"s));
+        }
+
+        DYNAMIC_SECTION( factory.first << " reporter lists reporters" ) {
+            std::vector<Catch::ReporterDescription> reporters(
+                { { "fake reporter", "fake description" } } );
+            reporter->listReporters(reporters);
+
+            auto listingString = sstream.str();
+            REQUIRE_THAT(listingString, Contains("fake reporter"s));
+        }
+
+        DYNAMIC_SECTION( factory.first << " reporter lists tests" ) {
+            Catch::TestCaseInfo fakeInfo{
+                ""s,
+                { "fake test name"_catch_sr, "[fakeTestTag]"_catch_sr },
+                { "fake-file.cpp", 123456789 } };
+            std::vector<Catch::TestCaseHandle> tests({ {&fakeInfo, nullptr} });
+            reporter->listTests(tests);
+
+            auto listingString = sstream.str();
+            REQUIRE_THAT( listingString,
+                          Contains( "fake test name"s ) &&
+                              Contains( "fakeTestTag"s ) );
+        }
+    }
+}