Tests: Report status on SIGINT and SIGTERM in LibWeb test runner

If you interrupt the test runner (Ctrl+C, SIGINT) or if the test runner
is gracefully being terminated (SIGTERM), it now reports the current
status of all the spawned views with their URL and, if an active test is
still being run, the time since the start of the test.

Hopefully this will help gain insight into which tests are hanging.

Tests/LibWeb/test-web/main.cpp

@@ -15,6 +15,7 @@
 #include <AK/ByteBuffer.h>
 #include <AK/Enumerate.h>
 #include <AK/LexicalPath.h>
+#include <AK/NumberFormat.h>
 #include <AK/QuickSort.h>
 #include <LibCore/ConfigFile.h>
 #include <LibCore/DirIterator.h>
@@ -35,7 +36,9 @@
 
 namespace TestWeb {
 
+static RefPtr<Core::Promise<Empty>> s_all_tests_complete;
 static Vector<ByteString> s_skipped_tests;
+static HashMap<WebView::ViewImplementation const*, Test const*> s_test_by_view;
 
 static constexpr StringView test_result_to_string(TestResult result)
 {
@@ -498,6 +501,8 @@ static void run_ref_test(TestWebView& view, Test& test, URL::URL const& url, int
 
 static void run_test(TestWebView& view, Test& test, Application& app)
 {
+    s_test_by_view.set(&view, &test);
+
     // Clear the current document.
     // FIXME: Implement a debug-request to do this more thoroughly.
     auto promise = Core::Promise<Empty>::construct();
@@ -659,7 +664,7 @@ static ErrorOr<int> run_tests(Core::AnonymousBuffer const& theme, Web::DevicePix
     bool log_on_one_line = app.verbosity < Application::VERBOSITY_LEVEL_LOG_TEST_DURATION && TRY(Core::System::isatty(STDOUT_FILENO));
     outln("Running {} tests...", tests.size());
 
-    auto all_tests_complete = Core::Promise<Empty>::construct();
+    s_all_tests_complete = Core::Promise<Empty>::construct();
     auto tests_remaining = tests.size();
     auto current_test = 0uz;
 
@@ -695,6 +700,7 @@ static ErrorOr<int> run_tests(Core::AnonymousBuffer const& theme, Web::DevicePix
 
         view->test_promise().when_resolved([&, run_next_test](auto result) {
             result.test.end_time = UnixDateTime::now();
+            s_test_by_view.remove(view);
 
             if (app.verbosity >= Application::VERBOSITY_LEVEL_LOG_TEST_DURATION) {
                 auto duration = result.test.end_time - result.test.start_time;
@@ -723,7 +729,7 @@ static ErrorOr<int> run_tests(Core::AnonymousBuffer const& theme, Web::DevicePix
                 non_passing_tests.append(move(result));
 
             if (--tests_remaining == 0)
-                all_tests_complete->resolve({});
+                s_all_tests_complete->resolve({});
             else
                 run_next_test();
         });
@@ -733,9 +739,11 @@ static ErrorOr<int> run_tests(Core::AnonymousBuffer const& theme, Web::DevicePix
         });
     }
 
-    MUST(all_tests_complete->await());
+    auto result_or_rejection = s_all_tests_complete->await();
 
-    if (log_on_one_line)
+    if (result_or_rejection.is_error())
+        outln("Halted; {} tests not executed.", tests_remaining);
+    else if (log_on_one_line)
         outln("\33[2K\rDone!");
 
     outln("==========================================================");
@@ -778,6 +786,41 @@ static ErrorOr<int> run_tests(Core::AnonymousBuffer const& theme, Web::DevicePix
     return fail_count + timeout_count + crashed_count;
 }
 
+static void handle_signal(int signal)
+{
+    VERIFY(signal == SIGINT || signal == SIGTERM);
+
+    // Quit our event loop. This makes `::exec()` return as soon as possible, and signals to WebView::Application that
+    // we should no longer automatically restart processes in `::process_did_exit()`.
+    Core::EventLoop::current().quit(0);
+
+    // Report current view statuses
+    dbgln();
+    dbgln("{} received. Active test views:", signal == SIGINT ? "SIGINT"sv : "SIGTERM"sv);
+    dbgln();
+
+    auto now = UnixDateTime::now();
+    WebView::ViewImplementation::for_each_view([&](WebView::ViewImplementation const& view) {
+        dbg("- View {}: {} ", view.view_id(), view.url());
+
+        auto maybe_test = s_test_by_view.get(&view);
+        if (maybe_test.has_value()) {
+            auto const& test = *maybe_test.release_value();
+            dbgln("(duration: {})", human_readable_time(now - test.start_time));
+        } else {
+            dbgln("(no active test)");
+        }
+
+        return IterationDecision::Continue;
+    });
+    dbgln();
+
+    // Stop running tests
+    s_all_tests_complete->reject(signal == SIGINT
+            ? Error::from_string_view("SIGINT received"sv)
+            : Error::from_string_view("SIGTERM received"sv));
+}
+
 }
 
 ErrorOr<int> ladybird_main(Main::Arguments arguments)
@@ -788,6 +831,9 @@ ErrorOr<int> ladybird_main(Main::Arguments arguments)
     auto app = TRY(TestWeb::Application::create(arguments, OptionalNone {}));
 #endif
 
+    Core::EventLoop::register_signal(SIGINT, TestWeb::handle_signal);
+    Core::EventLoop::register_signal(SIGTERM, TestWeb::handle_signal);
+
     auto theme_path = LexicalPath::join(WebView::s_ladybird_resource_root, "themes"sv, "Default.ini"sv);
     auto theme = TRY(Gfx::load_system_theme(theme_path.string()));