SQLStudio: Simplify action handling a bit

Most actions do not need to care about whether there is an open editor
tab, as we can (and should) disable those actions when there isn't an
open tab. We can also hide the verify_cast handling inside a helper
function.

Userland/DevTools/SQLStudio/MainWidget.cpp

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2022, Dylan Katz <dykatz@uw.edu>
+ * Copyright (c) 2022, Tim Flynn <trflynn89@serenityos.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
@@ -44,104 +45,83 @@ MainWidget::MainWidget()
     });
 
     m_open_action = GUI::CommonActions::make_open_action([&](auto&) {
-        auto maybe_load_path = GUI::FilePicker::get_open_filepath(window());
-        if (!maybe_load_path.has_value())
-            return;
-        auto lexical_path = LexicalPath(maybe_load_path.release_value());
-        open_script_from_file(lexical_path);
+        if (auto result = GUI::FilePicker::get_open_filepath(window()); result.has_value())
+            open_script_from_file(LexicalPath { result.release_value() });
     });
 
     m_save_action = GUI::CommonActions::make_save_action([&](auto&) {
-        if (!m_tab_widget)
-            return;
-        auto editor = dynamic_cast<ScriptEditor*>(m_tab_widget->active_widget());
-        if (!editor)
-            return;
-        auto save_attempt = editor->save();
-        if (save_attempt.is_error())
-            GUI::MessageBox::show_error(window(), DeprecatedString::formatted("Failed to save\n{}", save_attempt.release_error()));
+        auto* editor = active_editor();
+        VERIFY(editor);
+
+        if (auto result = editor->save(); result.is_error())
+            GUI::MessageBox::show_error(window(), DeprecatedString::formatted("Failed to save {}\n{}", editor->path(), result.error()));
     });
 
     m_save_as_action = GUI::CommonActions::make_save_as_action([&](auto&) {
-        if (!m_tab_widget)
-            return;
-        auto editor = dynamic_cast<ScriptEditor*>(m_tab_widget->active_widget());
-        if (!editor)
-            return;
-        auto save_attempt = editor->save_as();
-        if (save_attempt.is_error())
-            GUI::MessageBox::show_error(window(), DeprecatedString::formatted("Failed to save\n{}", save_attempt.release_error()));
+        auto* editor = active_editor();
+        VERIFY(editor);
+
+        if (auto result = editor->save_as(); result.is_error())
+            GUI::MessageBox::show_error(window(), DeprecatedString::formatted("Failed to save {}\n{}", editor->path(), result.error()));
     });
 
     m_save_all_action = GUI::Action::create("Save All", { Mod_Ctrl | Mod_Alt, Key_S }, [this](auto&) {
-        auto current_active_widget = m_tab_widget->active_widget();
-        ErrorOr<void> error {};
+        auto* editor = active_editor();
+        VERIFY(editor);
+
         m_tab_widget->for_each_child_widget([&](auto& child) {
-            auto editor = dynamic_cast<ScriptEditor*>(&child);
-            if (!editor)
-                return IterationDecision::Continue;
-            m_tab_widget->set_active_widget(editor);
-            auto save_attempt = editor->save();
-            if (save_attempt.is_error()) {
-                error = save_attempt.release_error();
+            auto& editor = verify_cast<ScriptEditor>(child);
+            m_tab_widget->set_active_widget(&editor);
+
+            if (auto result = editor.save(); result.is_error()) {
+                GUI::MessageBox::show_error(window(), DeprecatedString::formatted("Failed to save {}\n{}", editor.path(), result.error()));
+                return IterationDecision::Break;
+            } else if (!result.value()) {
                 return IterationDecision::Break;
             }
-            auto save_result = save_attempt.release_value();
-            if (save_result)
-                return IterationDecision::Continue;
-            return IterationDecision::Break;
+
+            return IterationDecision::Continue;
         });
-        if (error.is_error())
-            GUI::MessageBox::show_error(window(), DeprecatedString::formatted("Failed to save all files\n{}", error.release_error()));
-        m_tab_widget->set_active_widget(current_active_widget);
+
+        m_tab_widget->set_active_widget(editor);
     });
 
     m_copy_action = GUI::CommonActions::make_copy_action([&](auto&) {
-        if (!m_tab_widget)
-            return;
-        auto editor = dynamic_cast<ScriptEditor*>(m_tab_widget->active_widget());
-        if (!editor)
-            return;
+        auto* editor = active_editor();
+        VERIFY(editor);
+
         editor->copy_action().activate();
         update_editor_actions(editor);
     });
 
     m_cut_action = GUI::CommonActions::make_cut_action([&](auto&) {
-        if (!m_tab_widget)
-            return;
-        auto editor = dynamic_cast<ScriptEditor*>(m_tab_widget->active_widget());
-        if (!editor)
-            return;
+        auto* editor = active_editor();
+        VERIFY(editor);
+
         editor->cut_action().activate();
         update_editor_actions(editor);
     });
 
     m_paste_action = GUI::CommonActions::make_paste_action([&](auto&) {
-        if (!m_tab_widget)
-            return;
-        auto editor = dynamic_cast<ScriptEditor*>(m_tab_widget->active_widget());
-        if (!editor)
-            return;
+        auto* editor = active_editor();
+        VERIFY(editor);
+
         editor->paste_action().activate();
         update_editor_actions(editor);
     });
 
     m_undo_action = GUI::CommonActions::make_undo_action([&](auto&) {
-        if (!m_tab_widget)
-            return;
-        auto editor = dynamic_cast<ScriptEditor*>(m_tab_widget->active_widget());
-        if (!editor)
-            return;
+        auto* editor = active_editor();
+        VERIFY(editor);
+
         editor->document().undo();
         update_editor_actions(editor);
     });
 
     m_redo_action = GUI::CommonActions::make_redo_action([&](auto&) {
-        if (!m_tab_widget)
-            return;
-        auto editor = dynamic_cast<ScriptEditor*>(m_tab_widget->active_widget());
-        if (!editor)
-            return;
+        auto* editor = active_editor();
+        VERIFY(editor);
+
         editor->document().redo();
         update_editor_actions(editor);
     });
@@ -179,16 +159,12 @@ MainWidget::MainWidget()
     m_tab_widget = find_descendant_of_type_named<GUI::TabWidget>("script_tab_widget"sv);
 
     m_tab_widget->on_tab_close_click = [&](auto& widget) {
-        auto editor = dynamic_cast<ScriptEditor*>(&widget);
-        if (!editor)
-            return;
-        auto close_attempt = editor->attempt_to_close();
-        if (close_attempt.is_error()) {
-            GUI::MessageBox::show_error(window(), DeprecatedString::formatted("Failed to save before closing\n{}", close_attempt.release_error()));
-            return;
-        }
-        if (close_attempt.release_value()) {
-            m_tab_widget->remove_tab(widget);
+        auto& editor = verify_cast<ScriptEditor>(widget);
+
+        if (auto result = editor.attempt_to_close(); result.is_error()) {
+            GUI::MessageBox::show_error(window(), DeprecatedString::formatted("Failed to save {}\n{}", editor.path(), result.error()));
+        } else if (result.value()) {
+            m_tab_widget->remove_tab(editor);
             update_title();
             on_editor_change();
         }
@@ -298,9 +274,9 @@ void MainWidget::open_new_script()
 void MainWidget::open_script_from_file(LexicalPath const& file_path)
 {
     auto& editor = m_tab_widget->add_tab<ScriptEditor>(file_path.title());
-    auto maybe_error = editor.open_script_from_file(file_path);
-    if (maybe_error.is_error()) {
-        GUI::MessageBox::show_error(window(), DeprecatedString::formatted("Failed to open {}\n{}", file_path, maybe_error.release_error()));
+
+    if (auto result = editor.open_script_from_file(file_path); result.is_error()) {
+        GUI::MessageBox::show_error(window(), DeprecatedString::formatted("Failed to open {}\n{}", file_path, result.error()));
         return;
     }
 
@@ -320,15 +296,16 @@ bool MainWidget::request_close()
 {
     auto any_scripts_modified { false };
     auto is_script_modified = [&](auto& child) {
-        auto editor = dynamic_cast<ScriptEditor*>(&child);
-        if (!editor)
-            return IterationDecision::Continue;
-        if (editor->document().is_modified()) {
+        auto& editor = verify_cast<ScriptEditor>(child);
+
+        if (editor.document().is_modified()) {
             any_scripts_modified = true;
             return IterationDecision::Break;
         }
+
         return IterationDecision::Continue;
     };
+
     m_tab_widget->for_each_child_widget(is_script_modified);
     if (!any_scripts_modified)
         return true;
@@ -345,23 +322,29 @@ bool MainWidget::request_close()
 
     m_save_all_action->activate();
     any_scripts_modified = false;
+
     m_tab_widget->for_each_child_widget(is_script_modified);
     return !any_scripts_modified;
 }
 
+ScriptEditor* MainWidget::active_editor()
+{
+    if (!m_tab_widget || !m_tab_widget->active_widget())
+        return nullptr;
+    return verify_cast<ScriptEditor>(m_tab_widget->active_widget());
+}
+
 void MainWidget::update_title()
 {
-    auto editor = dynamic_cast<ScriptEditor*>(m_tab_widget->active_widget());
-    if (editor) {
+    if (auto* editor = active_editor())
         window()->set_title(DeprecatedString::formatted("{} - SQL Studio", editor->name()));
-    } else {
+    else
         window()->set_title("SQL Studio");
-    }
 }
 
 void MainWidget::on_editor_change()
 {
-    auto editor = dynamic_cast<ScriptEditor*>(m_tab_widget->active_widget());
+    auto* editor = active_editor();
     update_statusbar(editor);
     update_editor_actions(editor);
 }
@@ -390,18 +373,28 @@ void MainWidget::update_statusbar(ScriptEditor* editor)
 void MainWidget::update_editor_actions(ScriptEditor* editor)
 {
     if (!editor) {
+        m_save_action->set_enabled(false);
+        m_save_as_action->set_enabled(false);
+        m_save_all_action->set_enabled(false);
+        m_run_script_action->set_enabled(false);
+
         m_copy_action->set_enabled(false);
         m_cut_action->set_enabled(false);
         m_paste_action->set_enabled(false);
         m_undo_action->set_enabled(false);
         m_redo_action->set_enabled(false);
+
         return;
     }
 
+    m_save_action->set_enabled(true);
+    m_save_as_action->set_enabled(true);
+    m_save_all_action->set_enabled(true);
+    m_run_script_action->set_enabled(true);
+
     m_copy_action->set_enabled(editor->copy_action().is_enabled());
     m_cut_action->set_enabled(editor->cut_action().is_enabled());
     m_paste_action->set_enabled(editor->paste_action().is_enabled());
-
     m_undo_action->set_enabled(editor->undo_action().is_enabled());
     m_redo_action->set_enabled(editor->redo_action().is_enabled());
 }
@@ -492,7 +485,7 @@ void MainWidget::read_next_sql_statement_of_editor()
     if (auto statement_id = m_sql_client->prepare_statement(m_connection_id, sql_statement); statement_id.has_value()) {
         m_sql_client->async_execute_statement(*statement_id, {});
     } else {
-        auto* editor = dynamic_cast<ScriptEditor*>(m_tab_widget->active_widget());
+        auto* editor = active_editor();
         VERIFY(editor);
 
         GUI::MessageBox::show_error(window(), DeprecatedString::formatted("Could not parse {}\n{}", editor->path(), sql_statement));
@@ -501,16 +494,16 @@ void MainWidget::read_next_sql_statement_of_editor()
 
 Optional<DeprecatedString> MainWidget::read_next_line_of_editor()
 {
-    auto editor = dynamic_cast<ScriptEditor*>(m_tab_widget->active_widget());
+    auto* editor = active_editor();
     if (!editor)
         return {};
-    if (m_current_line_for_parsing < editor->document().line_count()) {
-        DeprecatedString result = editor->document().line(m_current_line_for_parsing).to_utf8();
-        m_current_line_for_parsing++;
-        return result;
-    } else {
+
+    if (m_current_line_for_parsing >= editor->document().line_count())
         return {};
-    }
+
+    auto result = editor->document().line(m_current_line_for_parsing).to_utf8();
+    ++m_current_line_for_parsing;
+    return result;
 }
 
 }

Userland/DevTools/SQLStudio/MainWidget.h

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2022, Dylan Katz <dykatz@uw.edu>
+ * Copyright (c) 2022, Tim Flynn <trflynn89@serenityos.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
@@ -31,6 +32,8 @@ public:
 private:
     MainWidget();
 
+    ScriptEditor* active_editor();
+
     void update_title();
     void on_editor_change();
     void update_statusbar(ScriptEditor*);