Add clang-tidy. (#368)

include/ftxui/component/component.hpp

@@ -8,7 +8,7 @@
 #include <vector>      // for vector
 
 #include "ftxui/component/component_base.hpp"     // for Component, Components
-#include "ftxui/component/component_options.hpp"  // for ButtonOption, CheckboxOption (ptr only), InputOption (ptr only), MenuEntryOption (ptr only), MenuOption, RadioboxOption (ptr only)
+#include "ftxui/component/component_options.hpp"  // for ButtonOption, CheckboxOption, InputOption (ptr only), MenuEntryOption (ptr only), MenuOption, RadioboxOption (ptr only)
 #include "ftxui/dom/elements.hpp"                 // for Element
 #include "ftxui/util/ref.hpp"  // for Ref, ConstStringRef, ConstStringListRef, StringRef
 

include/ftxui/component/component_options.hpp

@@ -3,11 +3,11 @@
 
 #include <chrono>                         // for milliseconds
 #include <ftxui/component/animation.hpp>  // for Duration, QuadraticInOut, Function
-#include <ftxui/dom/elements.hpp>  // for Decorator, bold, inverted, operator|, Element, nothing
-#include <ftxui/util/ref.hpp>  // for Ref
-#include <functional>          // for function
-#include <optional>            // for optional
-#include <string>              // for string, allocator
+#include <ftxui/dom/elements.hpp>         // for Element
+#include <ftxui/util/ref.hpp>             // for Ref
+#include <functional>                     // for function
+#include <optional>                       // for optional
+#include <string>                         // for string
 
 #include "ftxui/screen/color.hpp"  // for Color, Color::GrayDark, Color::White
 
@@ -17,10 +17,10 @@ namespace ftxui {
 /// |Radiobox::transform|, |MenuEntryOption::transform|,
 /// |MenuOption::transform|.
 struct EntryState {
-  std::string label; /// < The label to display.
-  bool state;        /// < The state of the button/checkbox/radiobox
-  bool active;       /// < Whether the entry is the active one.
-  bool focused;      /// < Whether the entry is one focused by the user.
+  std::string label;  /// < The label to display.
+  bool state;         /// < The state of the button/checkbox/radiobox
+  bool active;        /// < Whether the entry is the active one.
+  bool focused;       /// < Whether the entry is one focused by the user.
 };
 
 struct UnderlineOption {
@@ -70,7 +70,7 @@ struct AnimatedColorsOption {
 /// @brief Option for the MenuEntry component.
 /// @ingroup component
 struct MenuEntryOption {
-  std::function<Element(EntryState state)> transform;
+  std::function<Element(const EntryState& state)> transform;
   AnimatedColorsOption animated_colors;
 };
 
@@ -115,7 +115,7 @@ struct ButtonOption {
                                Color foreground_active);
 
   // Style:
-  std::function<Element(EntryState)> transform;
+  std::function<Element(const EntryState&)> transform;
   AnimatedColorsOption animated_colors;
 };
 
@@ -126,7 +126,7 @@ struct CheckboxOption {
   static CheckboxOption Simple();
 
   // Style:
-  std::function<Element(EntryState)> transform;
+  std::function<Element(const EntryState&)> transform;
 
   // Observer:
   /// Called when the user change the state.
@@ -156,7 +156,7 @@ struct RadioboxOption {
   static RadioboxOption Simple();
 
   // Style:
-  std::function<Element(EntryState)> transform;
+  std::function<Element(const EntryState&)> transform;
 
   // Observers:
   /// Called when the selected entry changes.

include/ftxui/component/event.hpp

@@ -54,7 +54,7 @@ struct Event {
   static const Event PageDown;
 
   // --- Custom ---
-  static Event Custom;
+  static const Event Custom;
 
   //--- Method section ---------------------------------------------------------
   bool is_character() const { return type_ == Type::Character; }

include/ftxui/dom/canvas.hpp

@@ -1,7 +1,7 @@
 #ifndef FTXUI_DOM_CANVAS_HPP
 #define FTXUI_DOM_CANVAS_HPP
 
-#include <stddef.h>       // for size_t
+#include <cstddef>        // for size_t
 #include <functional>     // for function
 #include <string>         // for string
 #include <unordered_map>  // for unordered_map
@@ -13,7 +13,7 @@ namespace ftxui {
 
 struct Canvas {
  public:
-  Canvas() {}
+  Canvas() = default;
   Canvas(int width, int height);
 
   // Getters:
@@ -114,7 +114,8 @@ struct Canvas {
 
   struct XYHash {
     size_t operator()(const XY& xy) const {
-      return static_cast<size_t>(xy.x * 1024 + xy.y);
+      constexpr size_t shift = 1024;
+      return size_t(xy.x) * shift + size_t(xy.y);
     }
   };
 

include/ftxui/dom/deprecated.hpp

@@ -1,5 +1,5 @@
-#ifndef FTXUI_DOM_DEPRECRATED_HPP
-#define FTXUI_DOM_DEPRECRATED_HPP
+#ifndef FTXUI_DOM_DEPRECATED_HPP
+#define FTXUI_DOM_DEPRECATED_HPP
 
 #include "ftxui/dom/elements.hpp"
 
@@ -9,7 +9,7 @@ Element vtext(std::wstring text);
 Elements paragraph(std::wstring text);
 }  // namespace ftxui
 
-#endif /* end of include guard: FTXUI_DOM_DEPRECRATED_HPP */
+#endif  // FTXUI_DOM_DEPRECATED_HPP
 
 // Copyright 2021 Arthur Sonzogni. All rights reserved.
 // Use of this source code is governed by the MIT license that can be found in

include/ftxui/dom/elements.hpp

@@ -35,7 +35,7 @@ Decorator operator|(Decorator, Decorator);
 // --- Widget ---
 Element text(std::string text);
 Element vtext(std::string text);
-Element separator(void);
+Element separator();
 Element separatorLight();
 Element separatorHeavy();
 Element separatorDouble();
@@ -45,18 +45,18 @@ Element separator(Pixel);
 Element separatorCharacter(std::string);
 Element separatorHSelector(float left,
                            float right,
-                           Color background,
-                           Color foreground);
+                           Color unselected_color,
+                           Color selected_color);
 Element separatorVSelector(float up,
                            float down,
-                           Color background,
-                           Color foreground);
-Element gauge(float ratio);
-Element gaugeLeft(float ratio);
-Element gaugeRight(float ratio);
-Element gaugeUp(float ratio);
-Element gaugeDown(float ratio);
-Element gaugeDirection(float ratio, GaugeDirection);
+                           Color unselected_color,
+                           Color selected_color);
+Element gauge(float progress);
+Element gaugeLeft(float progress);
+Element gaugeRight(float progress);
+Element gaugeUp(float progress);
+Element gaugeDown(float progress);
+Element gaugeDirection(float progress, GaugeDirection);
 Element border(Element);
 Element borderLight(Element);
 Element borderHeavy(Element);
@@ -64,14 +64,14 @@ Element borderDouble(Element);
 Element borderRounded(Element);
 Element borderEmpty(Element);
 Decorator borderStyled(BorderStyle);
-Decorator borderWith(Pixel);
+Decorator borderWith(const Pixel&);
 Element window(Element title, Element content);
 Element spinner(int charset_index, size_t image_index);
-Element paragraph(std::string text);
-Element paragraphAlignLeft(std::string text);
-Element paragraphAlignRight(std::string text);
-Element paragraphAlignCenter(std::string text);
-Element paragraphAlignJustify(std::string text);
+Element paragraph(const std::string& text);
+Element paragraphAlignLeft(const std::string& text);
+Element paragraphAlignRight(const std::string& text);
+Element paragraphAlignCenter(const std::string& text);
+Element paragraphAlignJustify(const std::string& text);
 Element graph(GraphFunction);
 Element emptyElement();
 Element canvas(ConstRef<Canvas>);
@@ -90,7 +90,7 @@ Element color(Color, Element);
 Element bgcolor(Color, Element);
 Decorator focusPosition(int x, int y);
 Decorator focusPositionRelative(float x, float y);
-Element automerge(Element);
+Element automerge(Element child);
 
 // --- Layout is
 // Horizontal, Vertical or stacked set of elements.
@@ -163,7 +163,7 @@ Dimensions Fit(Element&);
 
 // Include old definitions using wstring.
 #include "ftxui/dom/deprecated.hpp"
-#endif /* end of include guard: FTXUI_DOM_ELEMENTS_HPP */
+#endif  // FTXUI_DOM_ELEMENTS_HPP
 
 // Copyright 2020 Arthur Sonzogni. All rights reserved.
 // Use of this source code is governed by the MIT license that can be found in

include/ftxui/dom/flexbox_config.hpp

@@ -108,7 +108,7 @@ struct FlexboxConfig {
 
 }  // namespace ftxui
 
-#endif /* end of include guard: FTXUI_DOM_FLEXBOX_CONFIG_HPP */
+#endif  // FTXUI_DOM_FLEXBOX_CONFIG_HPP
 
 // Copyright 2021 Arthur Sonzogni. All rights reserved.
 // Use of this source code is governed by the MIT license that can be found in

include/ftxui/dom/node.hpp

@@ -20,6 +20,11 @@ class Node {
  public:
   Node();
   Node(Elements children);
+  Node(const Node&) = delete;
+  Node(const Node&&) = delete;
+  Node& operator=(const Node&) = delete;
+  Node& operator=(const Node&&) = delete;
+
   virtual ~Node();
 
   // Step 1: Compute layout requirement. Tell parent what dimensions this
@@ -50,12 +55,12 @@ class Node {
   Box box_;
 };
 
-void Render(Screen& screen, const Element& node);
+void Render(Screen& screen, const Element& element);
 void Render(Screen& screen, Node* node);
 
 }  // namespace ftxui
 
-#endif /* end of include guard: FTXUI_DOM_NODE_HPP */
+#endif  // FTXUI_DOM_NODE_HPP
 
 // Copyright 2020 Arthur Sonzogni. All rights reserved.
 // Use of this source code is governed by the MIT license that can be found in

include/ftxui/dom/requirement.hpp

@@ -28,7 +28,7 @@ struct Requirement {
 
 }  // namespace ftxui
 
-#endif /* end of include guard: FTXUI_DOM_REQUIREMENT_HPP */
+#endif  // FTXUI_DOM_REQUIREMENT_HPP
 
 // Copyright 2020 Arthur Sonzogni. All rights reserved.
 // Use of this source code is governed by the MIT license that can be found in

include/ftxui/dom/table.hpp

@@ -52,10 +52,10 @@ class Table {
   void Initialize(std::vector<std::vector<Element>>);
   friend TableSelection;
   std::vector<std::vector<Element>> elements_;
-  int input_dim_x_;
-  int input_dim_y_;
-  int dim_x_;
-  int dim_y_;
+  int input_dim_x_ = 0;
+  int input_dim_y_ = 0;
+  int dim_x_ = 0;
+  int dim_y_ = 0;
 };
 
 class TableSelection {

include/ftxui/dom/take_any_args.hpp

@@ -1,10 +1,13 @@
+#ifndef FTXUI_DOM_TAKE_ANY_ARGS_HPP
+#define FTXUI_DOM_TAKE_ANY_ARGS_HPP
+
 // IWYU pragma: private, include "ftxui/dom/elements.hpp"
 #include <type_traits>
 
 namespace ftxui {
 
 template <class T>
-void Merge(Elements&, T) {}
+void Merge(Elements& /*container*/, T /*element*/) {}
 
 template <>
 inline void Merge(Elements& container, Element element) {
@@ -38,6 +41,8 @@ TAKE_ANY_ARGS(dbox)
 TAKE_ANY_ARGS(hflow)
 }  // namespace ftxui
 
+#endif  // FTXUI_DOM_TAKE_ANY_ARGS_HPP
+
 // Copyright 2020 Arthur Sonzogni. All rights reserved.
 // Use of this source code is governed by the MIT license that can be found in
 // the LICENSE file.

include/ftxui/screen/box.hpp

@@ -9,15 +9,15 @@ struct Box {
   int y_min = 0;
   int y_max = 0;
 
-  static Box Intersection(Box a, Box b);
-  bool Contain(int x, int y);
+  static auto Intersection(Box a, Box b) -> Box;
+  bool Contain(int x, int y) const;
   bool operator==(const Box& other) const;
   bool operator!=(const Box& other) const;
 };
 
 }  // namespace ftxui
 
-#endif /* end of include guard: FTXUI_SCREEN_BOX_HPP */
+#endif  // FTXUI_SCREEN_BOX_HPP
 
 // Copyright 2020 Arthur Sonzogni. All rights reserved.
 // Use of this source code is governed by the MIT license that can be found in

include/ftxui/screen/color.hpp

@@ -1,8 +1,8 @@
-#ifndef FTXUI_SCREEN_COLOR
-#define FTXUI_SCREEN_COLOR
+#ifndef FTXUI_SCREEN_COLOR_HPP
+#define FTXUI_SCREEN_COLOR_HPP
 
-#include <stdint.h>  // for uint8_t
-#include <string>    // for wstring
+#include <cstdint>  // for uint8_t
+#include <string>   // for wstring
 
 #ifdef RGB
 // Workaround for wingdi.h (via Windows.h) defining macros that break things.
@@ -313,12 +313,8 @@ class Color {
     Palette256,
     TrueColor,
   };
-
-  ColorType type_;
-  union {
-    uint8_t index_ = 0;
-    uint8_t red_;
-  };
+  ColorType type_ = ColorType::Palette1;
+  uint8_t red_ = 0;
   uint8_t green_ = 0;
   uint8_t blue_ = 0;
 };
@@ -333,7 +329,7 @@ Color operator""_rgb(unsigned long long int combined);
 
 }  // namespace ftxui
 
-#endif /* end of include guard: FTXUI_COLOR_H_ */
+#endif  // FTXUI_SCREEN_COLOR_HPP
 
 // Copyright 2020 Arthur Sonzogni. All rights reserved.
 // Use of this source code is governed by the MIT license that can be found in

include/ftxui/screen/color_info.hpp

@@ -1,7 +1,7 @@
 #ifndef FTXUI_SCREEN_COLOR_INFO_HPP
 #define FTXUI_SCREEN_COLOR_INFO_HPP
 
-#include <stdint.h>
+#include <cstdint>
 #include <ftxui/screen/color.hpp>
 
 namespace ftxui {
@@ -23,7 +23,7 @@ ColorInfo GetColorInfo(Color::Palette16 index);
 
 }  // namespace ftxui
 
-#endif /* end of include guard: FTXUI_SCREEN_COLOR_INFO_HPP */
+#endif  // FTXUI_SCREEN_COLOR_INFO_HPP
 
 // Copyright 2020 Arthur Sonzogni. All rights reserved.
 // Use of this source code is governed by the MIT license that can be found in

include/ftxui/screen/deprecated.hpp

@@ -8,7 +8,7 @@ int wchar_width(wchar_t);
 int wstring_width(const std::wstring&);
 }  // namespace ftxui
 
-#endif /* end of include guard: FTXUI_SCREEN_DEPRECATED_HPP */
+#endif  // FTXUI_SCREEN_DEPRECATED_HPP
 
 // Copyright 2021 Arthur Sonzogni. All rights reserved.
 // Use of this source code is governed by the MIT license that can be found in

include/ftxui/screen/screen.hpp

@@ -1,5 +1,5 @@
-#ifndef FTXUI_SCREEN_SCREEN
-#define FTXUI_SCREEN_SCREEN
+#ifndef FTXUI_SCREEN_SCREEN_HPP
+#define FTXUI_SCREEN_SCREEN_HPP
 
 #include <memory>
 #include <string>  // for string, allocator, basic_string
@@ -14,6 +14,8 @@ namespace ftxui {
 /// @brief A unicode character and its associated style.
 /// @ingroup screen
 struct Pixel {
+  bool operator==(const Pixel& other) const;
+
   // The graphemes stored into the pixel. To support combining characters,
   // like: a⃦, this can potentially contains multiple codepoitns.
   std::string character = " ";
@@ -68,13 +70,12 @@ class Screen {
   int dimy() const { return dimy_; }
 
   // Move the terminal cursor n-lines up with n = dimy().
-  std::string ResetPosition(bool clear = false);
+  std::string ResetPosition(bool clear = false) const;
 
   // Fill with space.
   void Clear();
 
   void ApplyShader();
-  Box stencil;
 
   struct Cursor {
     int x = 0;
@@ -83,16 +84,20 @@ class Screen {
   Cursor cursor() const { return cursor_; }
   void SetCursor(Cursor cursor) { cursor_ = cursor; }
 
+  Box stencil;
+
  protected:
   int dimx_;
   int dimy_;
   std::vector<std::vector<Pixel>> pixels_;
   Cursor cursor_;
+
+ private:
 };
 
 }  // namespace ftxui
 
-#endif /* end of include guard: FTXUI_SCREEN_SCREEN */
+#endif  // FTXUI_SCREEN_SCREEN_HPP
 
 // Copyright 2020 Arthur Sonzogni. All rights reserved.
 // Use of this source code is governed by the MIT license that can be found in

include/ftxui/screen/terminal.hpp

@@ -1,5 +1,5 @@
-#ifndef FTXUI_CORE_TERMINAL_HPP
-#define FTXUI_CORE_TERMINAL_HPP
+#ifndef FTXUI_SCREEN_TERMINAL_HPP
+#define FTXUI_SCREEN_TERMINAL_HPP
 
 namespace ftxui {
 struct Dimensions {
@@ -22,7 +22,7 @@ Color ColorSupport();
 
 }  // namespace ftxui
 
-#endif /* end of include guard: FTXUI_CORE_TERMINAL_HPP */
+#endif  // FTXUI_SCREEN_TERMINAL_HPP
 
 // Copyright 2020 Arthur Sonzogni. All rights reserved.
 // Use of this source code is governed by the MIT license that can be found in