Fix workflow.

BUG:https://github.com/ArthurSonzogni/FTXUI/issues/1032

.github/workflows/build.yaml

@@ -55,6 +55,19 @@ jobs:
           gcovr: "5.0"
           opencppcoverage: true
 
+      - name: "Install Bazel"
+        uses: bazel-contrib/setup-bazel@0.14.0
+        with:
+          bazelisk-cache: true
+          disk-cache: ${{ github.workflow }}
+          repository-cache: true
+
+      - name: "Build with Bazel"
+        run: bazel build ...
+
+      - name: "Tests with Bazel"
+        run: bazel run tests
+
       # make sure coverage is only enabled for Debug builds, since it sets -O0
       # to make sure coverage has meaningful results
       - name: "Configure CMake"
@@ -104,7 +117,7 @@ jobs:
           --gcov-executable '${{ matrix.gcov_executable }}';
 
       - name: Windows - Test and coverage
-        if: runner.os == 'Windows' && false
+        if: runner.os == 'Windows'
         working-directory: ./build
         run: >
           OpenCppCoverage.exe

.gitignore

@@ -20,6 +20,10 @@ out/
 !flake.nix
 !ftxui.pc.in
 !iwyu.imp
+!WORKSPACE.bazel
+!BUILD.bazel
+!MODULE.bazel
+!.bazelrc
 
 # .github directory:
 !.github/**/*.yaml
@@ -29,6 +33,9 @@ out/
 !cmake/**/*.in
 !cmake/**/*.cmake
 
+# bazel directory:
+!bazel/**/*.bzl
+
 # doc directory:
 !doc/**/Doxyfile.in
 !doc/**/*.txt

BUILD.bazel

@@ -0,0 +1,251 @@
+# Copyright 2025 Arthur Sonzogni. All rights reserved.
+# Use of this source code is governed by the MIT license that can be found in
+# the LICENSE file.
+
+# TODO:
+# - Windows/MSVC support.
+#   - Pass /utf-8 to MSVC users depending on FTXUI.
+#   - Pass "FTXUI_MICROSOFT_TERMINAL_FALLBACK" to windows users.
+# - Support building benchmark.
+# - Support building examples.
+# - Support building fuzzer.
+# - Support building documentation.
+# - Enable the two tests timing out.
+# - Support WebAssembly
+
+load("@rules_cc//cc:defs.bzl", "cc_binary", "cc_library", "cc_test")
+load(":bazel/ftxui.bzl", "ftxui_cc_library", "generate_examples")
+
+package(default_visibility = ["//visibility:public"])
+
+# A meta target that depends on all the ftxui sub modules.
+alias(
+    name = "ftxui",
+    # Note that :component depends on :dom, which depends on :screen. Bazel
+    # doesn't really support "public" and "private" dependencies. They are all
+    # public. This is equivalent to depending on all the submodules.
+    actual = ":component",
+    visibility = ["//visibility:public"],
+)
+
+# ftxui:screen is a module that provides a screen buffer and color management
+# for terminal applications. A screen is a 2D array of cells, each cell can
+# contain a glyph, a color, and other attributes. The library also provides
+# functions to manipulate the screen.
+ftxui_cc_library(
+    name = "screen",
+    srcs = [
+        "src/ftxui/screen/box.cpp",
+        "src/ftxui/screen/color.cpp",
+        "src/ftxui/screen/color_info.cpp",
+        "src/ftxui/screen/image.cpp",
+        "src/ftxui/screen/screen.cpp",
+        "src/ftxui/screen/string.cpp",
+        "src/ftxui/screen/string_internal.hpp",
+        "src/ftxui/screen/terminal.cpp",
+        "src/ftxui/screen/util.hpp",
+    ],
+    hdrs = [
+        "include/ftxui/screen/box.hpp",
+        "include/ftxui/screen/color.hpp",
+        "include/ftxui/screen/color_info.hpp",
+        "include/ftxui/screen/deprecated.hpp",
+        "include/ftxui/screen/image.hpp",
+        "include/ftxui/screen/pixel.hpp",
+        "include/ftxui/screen/screen.hpp",
+        "include/ftxui/screen/string.hpp",
+        "include/ftxui/screen/terminal.hpp",
+        "include/ftxui/util/autoreset.hpp",
+        "include/ftxui/util/ref.hpp",
+    ],
+)
+
+# ftxui:dom is a library that provides a way to create and manipulate a
+# "document" that can be rendered to a screen. The document is a tree of nodes.
+# Nodes can be text, layouts, or various decorators. Users needs to compose
+# nodes to create a document. A document is responsive to the size of the
+# screen.
+ftxui_cc_library(
+    name = "dom",
+    srcs = [
+        "src/ftxui/dom/automerge.cpp",
+        "src/ftxui/dom/blink.cpp",
+        "src/ftxui/dom/bold.cpp",
+        "src/ftxui/dom/border.cpp",
+        "src/ftxui/dom/box_helper.cpp",
+        "src/ftxui/dom/box_helper.hpp",
+        "src/ftxui/dom/canvas.cpp",
+        "src/ftxui/dom/clear_under.cpp",
+        "src/ftxui/dom/color.cpp",
+        "src/ftxui/dom/composite_decorator.cpp",
+        "src/ftxui/dom/dbox.cpp",
+        "src/ftxui/dom/dim.cpp",
+        "src/ftxui/dom/flex.cpp",
+        "src/ftxui/dom/flexbox.cpp",
+        "src/ftxui/dom/flexbox_config.cpp",
+        "src/ftxui/dom/flexbox_helper.cpp",
+        "src/ftxui/dom/flexbox_helper.hpp",
+        "src/ftxui/dom/focus.cpp",
+        "src/ftxui/dom/frame.cpp",
+        "src/ftxui/dom/gauge.cpp",
+        "src/ftxui/dom/graph.cpp",
+        "src/ftxui/dom/gridbox.cpp",
+        "src/ftxui/dom/hbox.cpp",
+        "src/ftxui/dom/hyperlink.cpp",
+        "src/ftxui/dom/inverted.cpp",
+        "src/ftxui/dom/italic.cpp",
+        "src/ftxui/dom/linear_gradient.cpp",
+        "src/ftxui/dom/node.cpp",
+        "src/ftxui/dom/node_decorator.cpp",
+        "src/ftxui/dom/node_decorator.hpp",
+        "src/ftxui/dom/paragraph.cpp",
+        "src/ftxui/dom/reflect.cpp",
+        "src/ftxui/dom/scroll_indicator.cpp",
+        "src/ftxui/dom/selection.cpp",
+        "src/ftxui/dom/selection_style.cpp",
+        "src/ftxui/dom/separator.cpp",
+        "src/ftxui/dom/size.cpp",
+        "src/ftxui/dom/spinner.cpp",
+        "src/ftxui/dom/strikethrough.cpp",
+        "src/ftxui/dom/table.cpp",
+        "src/ftxui/dom/text.cpp",
+        "src/ftxui/dom/underlined.cpp",
+        "src/ftxui/dom/underlined_double.cpp",
+        "src/ftxui/dom/util.cpp",
+        "src/ftxui/dom/vbox.cpp",
+    ],
+    hdrs = [
+        "include/ftxui/dom/canvas.hpp",
+        "include/ftxui/dom/deprecated.hpp",
+        "include/ftxui/dom/direction.hpp",
+        "include/ftxui/dom/elements.hpp",
+        "include/ftxui/dom/flexbox_config.hpp",
+        "include/ftxui/dom/linear_gradient.hpp",
+        "include/ftxui/dom/node.hpp",
+        "include/ftxui/dom/requirement.hpp",
+        "include/ftxui/dom/selection.hpp",
+        "include/ftxui/dom/table.hpp",
+        "include/ftxui/dom/take_any_args.hpp",
+    ],
+    deps = [":screen"],
+)
+
+# ftxui:component is a library to create "dynamic" component renderering and
+# updating a ftxui::dom document on the screen. It is a higher level API than
+# ftxui:dom.
+#
+# The module is required if your program needs to respond to user input. It
+# defines a set of ftxui::Component. These components can be utilized to
+# navigate using the arrow keys and/or cursor. There are several builtin widgets
+# like checkbox/inputbox/etc to interact with. You can combine them, or even
+# define your own custom components.
+ftxui_cc_library(
+    name = "component",
+    srcs = [
+        "src/ftxui/component/animation.cpp",
+        "src/ftxui/component/button.cpp",
+        "src/ftxui/component/catch_event.cpp",
+        "src/ftxui/component/checkbox.cpp",
+        "src/ftxui/component/collapsible.cpp",
+        "src/ftxui/component/component.cpp",
+        "src/ftxui/component/component_options.cpp",
+        "src/ftxui/component/container.cpp",
+        "src/ftxui/component/dropdown.cpp",
+        "src/ftxui/component/event.cpp",
+        "src/ftxui/component/hoverable.cpp",
+        "src/ftxui/component/input.cpp",
+        "src/ftxui/component/loop.cpp",
+        "src/ftxui/component/maybe.cpp",
+        "src/ftxui/component/menu.cpp",
+        "src/ftxui/component/modal.cpp",
+        "src/ftxui/component/radiobox.cpp",
+        "src/ftxui/component/renderer.cpp",
+        "src/ftxui/component/resizable_split.cpp",
+        "src/ftxui/component/screen_interactive.cpp",
+        "src/ftxui/component/slider.cpp",
+        "src/ftxui/component/terminal_input_parser.cpp",
+        "src/ftxui/component/terminal_input_parser.hpp",
+        "src/ftxui/component/util.cpp",
+        "src/ftxui/component/window.cpp",
+    ],
+    hdrs = [
+        "include/ftxui/component/animation.hpp",
+        "include/ftxui/component/captured_mouse.hpp",
+        "include/ftxui/component/component.hpp",
+        "include/ftxui/component/component_base.hpp",
+        "include/ftxui/component/component_options.hpp",
+        "include/ftxui/component/event.hpp",
+        "include/ftxui/component/loop.hpp",
+        "include/ftxui/component/mouse.hpp",
+        "include/ftxui/component/receiver.hpp",
+        "include/ftxui/component/screen_interactive.hpp",
+        "include/ftxui/component/task.hpp",
+    ],
+    linkopts = ["-lpthread"],
+    deps = [":dom"],
+)
+
+# FTXUI's tests
+cc_test(
+    name = "tests",
+    testonly = True,
+    srcs = [
+        "src/ftxui/component/animation_test.cpp",
+        "src/ftxui/component/button_test.cpp",
+        "src/ftxui/component/collapsible_test.cpp",
+        "src/ftxui/component/component_test.cpp",
+        "src/ftxui/component/container_test.cpp",
+        "src/ftxui/component/dropdown_test.cpp",
+        "src/ftxui/component/hoverable_test.cpp",
+        "src/ftxui/component/input_test.cpp",
+        "src/ftxui/component/menu_test.cpp",
+        "src/ftxui/component/modal_test.cpp",
+        "src/ftxui/component/radiobox_test.cpp",
+        "src/ftxui/component/receiver_test.cpp",
+        "src/ftxui/component/resizable_split_test.cpp",
+        "src/ftxui/component/slider_test.cpp",
+        "src/ftxui/component/terminal_input_parser_test.cpp",
+        "src/ftxui/component/terminal_input_parser_test_fuzzer.cpp",
+        "src/ftxui/component/toggle_test.cpp",
+        "src/ftxui/dom/blink_test.cpp",
+        "src/ftxui/dom/bold_test.cpp",
+        "src/ftxui/dom/border_test.cpp",
+        "src/ftxui/dom/canvas_test.cpp",
+        "src/ftxui/dom/color_test.cpp",
+        "src/ftxui/dom/dbox_test.cpp",
+        "src/ftxui/dom/dim_test.cpp",
+        "src/ftxui/dom/flexbox_helper_test.cpp",
+        "src/ftxui/dom/flexbox_test.cpp",
+        "src/ftxui/dom/gauge_test.cpp",
+        "src/ftxui/dom/gridbox_test.cpp",
+        "src/ftxui/dom/hbox_test.cpp",
+        "src/ftxui/dom/hyperlink_test.cpp",
+        "src/ftxui/dom/italic_test.cpp",
+        "src/ftxui/dom/linear_gradient_test.cpp",
+        "src/ftxui/dom/scroll_indicator_test.cpp",
+        "src/ftxui/dom/separator_test.cpp",
+        "src/ftxui/dom/spinner_test.cpp",
+        "src/ftxui/dom/table_test.cpp",
+        "src/ftxui/dom/text_test.cpp",
+        "src/ftxui/dom/underlined_test.cpp",
+        "src/ftxui/dom/vbox_test.cpp",
+        "src/ftxui/screen/color_test.cpp",
+        "src/ftxui/screen/string_test.cpp",
+        "src/ftxui/util/ref_test.cpp",
+
+        # TODO: Enable the two tests timing out with Bazel:
+        # - "src/ftxui/component/screen_interactive_test.cpp",
+        # - "src/ftxui/dom/selection_test.cpp",
+    ],
+    copts = ["-std=c++20"],
+    includes = [
+        "include",
+        "src",
+    ],
+    deps = [
+        "//:ftxui",
+        "@googletest//:gtest_main",
+    ],
+)
+
+generate_examples()

CHANGELOG.md

@@ -1,8 +1,37 @@
 Changelog
 =========
 
-current (development) 
----------------------
+Development
+-----------
+### Component
+- Bugfix: Fix a crash with ResizeableSplit. See #1023.
+  - Clamp screen size to terminal size.
+  - Disallow `ResizeableSplit` with negative size.
+
+### Dom
+- Bugfix: Disallow specifying a negative size constraint. See #1023.
+
+
+6.0.2 (2025-03-30)
+-----
+
+### Component
+- BugFix: Fix major crash on Windows affecting all components. See #1020
+- BugFix: Fix focusRelative.
+
+6.0.1 (2025-03-28)
+-----
+
+Same as v6.0.0.
+
+Due to a problem tag v6.0.0 was replaced. This isn't a good practice and affect
+developers that started using it in the short timeframe. Submitting a new
+release with the same content is the best way to fix this.
+
+See #1017 and #1019.
+
+6.0.0 (2025-03-23)
+-----
 
 ### Component
 - Feature: Add support for raw input. Allowing more keys to be detected.
@@ -71,6 +100,10 @@ current (development)
   - See `selectionStyleReset` decorator.
 - Breaking change: Change how "focus"/"select" are handled. This fixes the
   behavior.
+- Breaking change: `Component::OnRender()` becomes the method to override to
+  render a component. This replaces `Component::Render()` that is still in use
+  to call the rendering method on the children. This change allows to fix a
+  couple of issues around focus handling.
 
 ### Screen
 - Feature: Add `Box::IsEmpty()`.

CMakeLists.txt

@@ -2,7 +2,7 @@ cmake_minimum_required(VERSION 3.12)
 
 project(ftxui
   LANGUAGES CXX
-  VERSION 5.0.0
+  VERSION 6.0.2
   DESCRIPTION "C++ Functional Terminal User Interface."
 )
 

MODULE.bazel

@@ -0,0 +1,20 @@
+# FTXUI Module.
+module(
+    name = "ftxui",
+    version = "6.0.3",
+)
+
+# Build deps.
+bazel_dep(name = "rules_cc", version = "0.0.17")
+bazel_dep(name = "platforms", version = "0.0.10")
+bazel_dep(name = "bazel_skylib", version = "1.7.1")
+
+# Test deps.
+bazel_dep(name = "googletest", version = "1.15.2")
+
+# Toolchain deps.
+#cc_configure = use_extension(
+#"@rules_cc//bzlmod:extensions.bzl",
+#"cc_configure",
+#)
+#use_repo(cc_configure, "local_config_cc_toolchains")

README.md

@@ -372,7 +372,7 @@ include(FetchContent)
 
 FetchContent_Declare(ftxui
   GIT_REPOSITORY https://github.com/ArthurSonzogni/ftxui
-  GIT_TAG v5.0.0
+  GIT_TAG v6.0.2
 )
 
 FetchContent_GetProperties(ftxui)
@@ -388,7 +388,7 @@ If you don't, FTXUI may be used from the following packages:
 - [conan.io](https://conan.io/center/ftxui)
 - [openSUSE](https://build.opensuse.org/package/show/devel:libraries:c_c++/ftxui)
 - 
-[![Packaging status](https://repology.org/badge/vertical-allrepos/ftxui.svg)](https://repology.org/project/ftxui/versions)
+[![Packaging status](https://repology.org/badge/vertical-allrepos/libftxui.svg)](https://repology.org/project/libftxui/versions)
 
 If you choose to build and link FTXUI yourself, `ftxui-component` must be first in the linking order relative to the other FTXUI libraries, i.e.
 ```bash

WORKSPACE.bazel

@@ -0,0 +1 @@
+workspace(name = "ftxui")

bazel/ftxui.bzl

@@ -0,0 +1,44 @@
+# ftxui_common.bzl
+
+load("@rules_cc//cc:defs.bzl", "cc_library")
+
+def ftxui_cc_library(
+        name,
+        srcs,
+        hdrs,
+        linkopts = [],
+        deps = []):
+    cc_library(
+        name = name,
+        srcs = srcs,
+        hdrs = hdrs,
+        linkopts = linkopts,
+        deps = deps,
+        strip_include_prefix = "",
+        include_prefix = "",
+        includes = [
+            "include",
+            "src",
+        ],
+        copts = ["-std=c++17"],
+        visibility = ["//visibility:public"],
+    )
+
+def generate_examples():
+    cpp_files = native.glob(["examples/**/*.cpp"])
+
+    for src in cpp_files:
+        # Skip failing examples due to the color_info_sorted_2d.ipp dependency.
+        if src == "examples/component/homescreen.cpp" or \
+           src == "examples/dom/color_info_palette256.cpp" or \
+           src == "examples/dom/color_gallery.cpp":
+            continue
+
+        # Turn "examples/component/button.cpp" → "example_component_button"
+        name = src.replace("/", "_").replace(".cpp", "")
+
+        native.cc_binary(
+            name = name,
+            srcs = [src],
+            deps = ["//:component"],
+        )

examples/component/slider_direction.cpp

@@ -19,7 +19,7 @@ using namespace ftxui;
 int main() {
   auto screen = ScreenInteractive::TerminalOutput();
   std::array<int, 30> values;
-  for (int i = 0; i < values.size(); ++i) {
+  for (size_t i = 0; i < values.size(); ++i) {
     values[i] = 50 + 20 * std::sin(i * 0.3);
   }
 

examples/dom/color_truecolor_RGB.cpp

@@ -12,7 +12,6 @@
 int main() {
   using namespace ftxui;
 
-  int saturation = 255;
   Elements red_line;
   Elements green_line;
   Elements blue_line;

examples/dom/graph.cpp

@@ -10,6 +10,7 @@
 #include <memory>                   // for shared_ptr
 #include <string>                   // for operator<<, string
 #include <thread>                   // for sleep_for
+#include <utility>                  // for ignore
 #include <vector>                   // for vector
 
 #include "ftxui/dom/node.hpp"  // for Render
@@ -49,6 +50,7 @@ int main() {
 
   std::string reset_position;
   for (int i = 0;; ++i) {
+    std::ignore = i;
     auto document = hbox({
         vbox({
             graph(std::ref(my_graph)),

src/ftxui/component/menu_test.cpp

@@ -266,7 +266,7 @@ TEST(MenuTest, MenuEntryIndex) {
   menu->OnEvent(Event::ArrowDown);
   menu->OnEvent(Event::ArrowDown);
   menu->OnEvent(Event::Return);
-  for (int index = 0; index < menu->ChildCount(); index++) {
+  for (size_t index = 0; index < menu->ChildCount(); index++) {
     EXPECT_EQ(menu->ChildAt(index)->Index(), index);
   }
 }

src/ftxui/component/resizable_split.cpp

@@ -77,16 +77,16 @@ class ResizableSplitBase : public ComponentBase {
 
     switch (options_->direction()) {
       case Direction::Left:
-        options_->main_size() = event.mouse().x - box_.x_min;
+        options_->main_size() = std::max(0, event.mouse().x - box_.x_min);
         return true;
       case Direction::Right:
-        options_->main_size() = box_.x_max - event.mouse().x;
+        options_->main_size() = std::max(0, box_.x_max - event.mouse().x);
         return true;
       case Direction::Up:
-        options_->main_size() = event.mouse().y - box_.y_min;
+        options_->main_size() = std::max(0, event.mouse().y - box_.y_min);
         return true;
       case Direction::Down:
-        options_->main_size() = box_.y_max - event.mouse().y;
+        options_->main_size() = std::max(0, box_.y_max - event.mouse().y);
         return true;
     }
 

src/ftxui/component/screen_interactive.cpp

@@ -34,6 +34,7 @@
 #include "ftxui/dom/requirement.hpp"                  // for Requirement
 #include "ftxui/screen/pixel.hpp"                     // for Pixel
 #include "ftxui/screen/terminal.hpp"                  // for Dimensions, Size
+#include "ftxui/screen/util.hpp"                      // for util::clamp
 
 #if defined(_WIN32)
 #define DEFINE_CONSOLEV2_PROPERTIES
@@ -917,15 +918,15 @@ void ScreenInteractive::Draw(Component component) {
       break;
     case Dimension::TerminalOutput:
       dimx = terminal.dimx;
-      dimy = document->requirement().min_y;
+      dimy = util::clamp(document->requirement().min_y, 0, terminal.dimy);
       break;
     case Dimension::Fullscreen:
       dimx = terminal.dimx;
       dimy = terminal.dimy;
       break;
     case Dimension::FitComponent:
-      dimx = std::min(document->requirement().min_x, terminal.dimx);
-      dimy = std::min(document->requirement().min_y, terminal.dimy);
+      dimx = util::clamp(document->requirement().min_x, 0, terminal.dimx);
+      dimy = util::clamp(document->requirement().min_y, 0, terminal.dimy);
       break;
   }
 

src/ftxui/dom/focus.cpp

@@ -36,7 +36,7 @@ Decorator focusPositionRelative(float x, float y) {
 
     void ComputeRequirement() override {
       NodeDecorator::ComputeRequirement();
-      requirement_.focused.enabled = false;
+      requirement_.focused.enabled = true;
       requirement_.focused.node = this;
       requirement_.focused.box.x_min = int(float(requirement_.min_x) * x_);
       requirement_.focused.box.y_min = int(float(requirement_.min_y) * y_);

src/ftxui/dom/node.cpp

@@ -125,27 +125,27 @@ void Render(Screen& screen, Node* node, Selection& selection) {
     node->Select(selection);
   }
 
-  // Setting the cursor to the right position allow folks using CJK (China,
-  // Japanese, Korean, ...) characters to see their [input method editor]
-  // displayed at the right location. See [issue].
-  //
-  // [input method editor]:
-  // https://en.wikipedia.org/wiki/Input_method
-  //
-  // [issue]:
-  // https://github.com/ArthurSonzogni/FTXUI/issues/2#issuecomment-505282355
-  //
-  // Unfortunately, Microsoft terminal do not handle properly hiding the
-  // cursor. Instead the character under the cursor is hidden, which is a big
-  // problem. As a result, we can't enable setting cursor to the right
-  // location. It will be displayed at the bottom right corner.
-  // See:
-  // https://github.com/microsoft/terminal/issues/1203
-  // https://github.com/microsoft/terminal/issues/3093
   if (node->requirement().focused.enabled
 #if defined(FTXUI_MICROSOFT_TERMINAL_FALLBACK)
-      ||
-      node->requirement().focused.cursor_shape == Screen::Cursor::Shape::Hidden
+      // Setting the cursor to the right position allow folks using CJK (China,
+      // Japanese, Korean, ...) characters to see their [input method editor]
+      // displayed at the right location. See [issue].
+      //
+      // [input method editor]:
+      // https://en.wikipedia.org/wiki/Input_method
+      //
+      // [issue]:
+      // https://github.com/ArthurSonzogni/FTXUI/issues/2#issuecomment-505282355
+      //
+      // Unfortunately, Microsoft terminal do not handle properly hiding the
+      // cursor. Instead the character under the cursor is hidden, which is a
+      // big problem. As a result, we can't enable setting cursor to the right
+      // location. It will be displayed at the bottom right corner.
+      // See:
+      // https://github.com/microsoft/terminal/issues/1203
+      // https://github.com/microsoft/terminal/issues/3093
+      &&
+      node->requirement().focused.cursor_shape != Screen::Cursor::Shape::Hidden
 #endif
   ) {
     screen.SetCursor(Screen::Cursor{

src/ftxui/dom/selection_test.cpp

@@ -127,8 +127,6 @@ TEST(SelectionTest, SelectionOnChangeSquashedEvents) {
 }
 
 TEST(SelectionTest, StyleSelection) {
-  int selectionChangeCounter = 0;
-
   auto element = hbox({
       text("Lorem "),
       text("ipsum") | selectionColor(Color::Red),

src/ftxui/dom/size.cpp

@@ -19,7 +19,7 @@ class Size : public Node {
       : Node(unpack(std::move(child))),
         direction_(direction),
         constraint_(constraint),
-        value_(value) {}
+        value_(std::max(0, value)) {}
 
   void ComputeRequirement() override {
     Node::ComputeRequirement();