Merge baa5973128 into 08b8a3b28f

* Bazel: general improvements.

Improve the Bazel build. Attempt to fix previous errors recorded while
trying to publish ftxui in the Bazel Central Registry:
- https://github.com/bazelbuild/bazel-central-registry/pull/4485
- https://buildkite.com/bazel/bcr-presubmit/builds/13601#01968b61-f5b2-4d16-94d0-c87a03a1a23b

Test against "recent" platforms
-------------------------------

Previously, I got the error:
```
gcc: error: unrecognized command line option '-std-c++20'; did you mean '-std-c++2a'?
```
This was due to using old distribution like ubuntu 2004. Test against
newer platforms only to avoid GCC version<-9.x.y

Downgrade gtest version.
------------------------

I suspect this caused the Bazel Central Registry error:
```
file:///workdir/modules/googletest/1.15.2/MODULE.bazel:68:20: name 'use_repo_rule' is not defined
```
Specifying using bazelmod fixes the issue. Thanks @robinlinden

Tag gtest as dev_dependency
---------------------------

Presumably, this should avoid dependants to fetch it?

Enable --features-layering_check
--------------------------------

Aka clang `-Wprivate-header`. Fix the encountered errors.

Use clang in the CI
-------------------

The CI was defining clang/gcc in the matrix, but was not using it. Fix
the bug.

.bazelrc

@@ -0,0 +1,7 @@
+build --features=layering_check
+build --enable_bzlmod
+
+build --enable_platform_specific_config
+build:linux --cxxopt=-std=c++20
+build:macos --cxxopt=-std=c++20
+build:windows --cxxopt=-std:c++20

.bcr/presubmit.yml

@@ -1,21 +1,36 @@
 matrix:
-  platform:
-  - centos7
-  - debian10
-  - ubuntu2004
-  - macos
-  - windows
-  bazel: [6.x, 7.x, 8.x]
+  bazel:
+    - 7.x
+    - 8.x
+    - rolling
+  unix_platform:
+    - debian11
+    - ubuntu2204
+    - macos
+    - macos_arm64
+  win_platform:
+    - windows
+
 tasks:
-  verify_targets:
-    name: Build and test.
-    platform: ${{ platform }}
+
+  unix_test:
+    name: Verify build targets on Unix
+    platform: ${{ unix_platform }}
     bazel: ${{ bazel }}
+    build_flags:
+    - --cxxopt=-std=c++20
     build_targets:
-    - '@ftxui//:ftxui'
-    - '@ftxui//:screen'
     - '@ftxui//:dom'
     - '@ftxui//:component'
-    test_targets:
-    - '@ftxui//:tests'
+    - '@ftxui//:screen'
 
+  windows_test:
+    name: Verify build targets
+    platform: ${{ win_platform }}
+    bazel: ${{ bazel }}
+    build_flags:
+    - --cxxopt=/std:c++20
+    build_targets:
+    - '@ftxui//:dom'
+    - '@ftxui//:component'
+    - '@ftxui//:screen'

.github/workflows/build.yaml

@@ -14,25 +14,30 @@ on:
 jobs:
 
   test_bazel:
-    name: "Bazel, ${{ matrix.compiler }}, ${{ matrix.os }}"
+    name: "Bazel, ${{ matrix.cxx }}, ${{ matrix.os }}"
     strategy:
       fail-fast: false
       matrix:
         include:
           - os: ubuntu-latest
-            compiler: gcc
+            cxx: g++
+            cc: gcc
 
           - os: ubuntu-latest
-            compiler: llvm
+            cxx: clang++
+            cc: clang
 
           - os: macos-latest
-            compiler: llvm
+            cxx: g++
+            cc: gcc
 
           - os: macos-latest
-            compiler: gcc
+            cxx: clang++
+            cc: clang
 
           - os: windows-latest
-            compiler: cl
+            cxx: cl
+            cc: cl
 
     runs-on: ${{ matrix.os }}
     steps:
@@ -40,10 +45,16 @@ jobs:
         uses: actions/checkout@v3
 
       - name: "Build with Bazel"
+        env:
+          CC: ${{ matrix.cc }}
+          CXX: ${{ matrix.cxx }}
         run: bazel build ...
 
       - name: "Tests with Bazel"
-        run: bazel run tests
+        env:
+          CC: ${{ matrix.cc }}
+          CXX: ${{ matrix.cxx }}
+        run: bazel test --test_output=all ...
 
   test_cmake:
     name: "CMake, ${{ matrix.compiler }}, ${{ matrix.os }}"

BUILD.bazel

@@ -12,23 +12,19 @@
 load("@rules_cc//cc:defs.bzl", "cc_binary", "cc_library", "cc_test")
 load(":bazel/ftxui.bzl", "ftxui_cc_library")
 load(":bazel/ftxui.bzl", "generate_examples")
-load(":bazel/ftxui.bzl", "cpp20")
 load(":bazel/ftxui.bzl", "windows_copts")
 load(":bazel/ftxui.bzl", "pthread_linkopts")
 
-package(default_visibility = ["//visibility:public"])
+# A meta target depending on all of the ftxui submodules.
+# Note that component depends on dom and screen, so ftxui is just an alias for 
+# component.
+# ┌component──┐
+# │┌dom──────┐│
+# ││┌screen─┐││
+# └┴┴───────┴┴┘
+alias(name = "ftxui", actual = ":component")
 
-# 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
+# @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.
@@ -60,7 +56,7 @@ ftxui_cc_library(
     ],
 )
 
-# ftxui:dom is a library that provides a way to create and manipulate a
+# @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
@@ -130,7 +126,7 @@ ftxui_cc_library(
     deps = [":screen"],
 )
 
-# ftxui:component is a library to create "dynamic" component renderering and
+# @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.
 #
@@ -167,6 +163,13 @@ ftxui_cc_library(
         "src/ftxui/component/terminal_input_parser.hpp",
         "src/ftxui/component/util.cpp",
         "src/ftxui/component/window.cpp",
+
+        # Private header from ftxui:dom.
+        "src/ftxui/dom/node_decorator.hpp",
+
+        # Private header from ftxui:screen.
+        "src/ftxui/screen/string_internal.hpp",
+        "src/ftxui/screen/util.hpp",
     ],
     hdrs = [
         "include/ftxui/component/animation.hpp",
@@ -182,7 +185,10 @@ ftxui_cc_library(
         "include/ftxui/component/task.hpp",
     ],
     linkopts = pthread_linkopts(),
-    deps = [":dom"],
+    deps = [
+        ":dom",
+        ":screen",
+    ],
 )
 
 # FTXUI's tests
@@ -205,7 +211,6 @@ cc_test(
         "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",
@@ -233,6 +238,17 @@ cc_test(
         "src/ftxui/screen/string_test.cpp",
         "src/ftxui/util/ref_test.cpp",
 
+        # Private header from ftxui:screen for string_test.cpp.
+        "src/ftxui/screen/string_internal.hpp",
+
+        # Private header from ftxui::component for
+        # terminal_input_parser_test.cpp.
+        "src/ftxui/component/terminal_input_parser.hpp",
+
+        # Private header from ftxui::dom for
+        # flexbox_helper_test.cpp.
+        "src/ftxui/dom/flexbox_helper.hpp",
+
         # TODO: Enable the two tests timing out with Bazel:
         # - "src/ftxui/component/screen_interactive_test.cpp",
         # - "src/ftxui/dom/selection_test.cpp",
@@ -241,9 +257,12 @@ cc_test(
         "include",
         "src",
     ],
-    copts = cpp20() + windows_copts(),
+    copts = windows_copts(),
     deps = [
-        "//:ftxui",
+        ":screen",
+        ":dom",
+        ":component",
+        "@googletest//:gtest",
         "@googletest//:gtest_main",
     ],
 )

CHANGELOG.md

@@ -1,9 +1,20 @@
 Changelog
 =========
 
-Future release
+6.1.9 (2025-05-07)
 ------------
 
+### Build
+If all goes well (pending), ftxui should appear in the Bazel central repository.
+It can be imported into your project using the following lines:
+
+**MODULE.bazel**
+```bazel
+bazel_dep(name = "ftxui", version = "6.1.9")
+```
+
+Thanks @robinlinden and @kcc for the reviews.
+
 ### dom
 - Bugfix: Restore the `dbox` behavior from ftxui 5.0.0. To apply bgcolor
   blending between the two layers, a new `dboxBlend` will be added.
@@ -14,13 +25,6 @@ Future release
 ### Build
 - Feature: Support `bazel` build system. See #1032.
   Proposed by Kostya Serebryany @kcc
-  If all goes well (pending), it should appear in the Bazel central repository.
-  It can be imported into your project using the following lines:
-
-  **MODULE.bazel**
-  ```bazel
-  bazel_dep(name = "ftxui", version = "6.1.8")
-  ```
 
   **BUILD.bazel**
   ```bazel

CMakeLists.txt

@@ -2,7 +2,7 @@ cmake_minimum_required(VERSION 3.12)
 
 project(ftxui
   LANGUAGES CXX
-  VERSION 6.1.8
+  VERSION 6.1.9
   DESCRIPTION "C++ Functional Terminal User Interface."
 )
 

MODULE.bazel

@@ -1,9 +1,13 @@
-# FTXUI Module.
-module(name = "ftxui", version = "6.1.8", compatibility_level = 6)
+# FTXUI module.
+module(
+    name = "ftxui",
+    version = "6.1.9",
+    compatibility_level = 6,
+)
 
-# Build deps.
+# Build dependencies.
 bazel_dep(name = "rules_cc", version = "0.1.1")
-bazel_dep(name = "platforms", version = "0.0.11")
+bazel_dep(name = "platforms", version = "0.0.10")
 
-# Test deps.
-bazel_dep(name = "googletest", version = "1.16.0.bcr.1")
+# Test dependencies.
+bazel_dep(name = "googletest", version = "1.14.0.bcr.1", dev_dependency = True)

README.md

@@ -42,15 +42,24 @@ A simple cross-platform C++ library for terminal based user interfaces!
  * No dependencies
  * **Cross platform**: Linux/MacOS (main target), WebAssembly, Windows (Thanks to contributors!).
  * Learn by [examples](#documentation), and [tutorials](#documentation)
- * Multiple packages: CMake [FetchContent]([https://bewagner.net/programming/2020/05/02/cmake-fetchcontent/](https://cmake.org/cmake/help/latest/module/FetchContent.html)) (preferred),Bazel, vcpkg, pkgbuild, conan.
+ * Multiple packages:
+     - CMake [FetchContent]([https://bewagner.net/programming/2020/05/02/cmake-fetchcontent/](https://cmake.org/cmake/help/latest/module/FetchContent.html)) (preferred)
+     - [Bazel](https://registry.bazel.build/modules/ftxui)
+     - [vcpkg](https://vcpkg.link/ports/ftxui)
+     - [Conan](https://conan.io/center/recipes/ftxui) [Debian package](https://tracker.debian.org/pkg/ftxui)
+     - [Ubuntu package](https://launchpad.net/ubuntu/+source/ftxui)
+     - [Arch Linux](https://aur.archlinux.org/packages/ftxui/)
+     - [OpenSUSE](https://build.opensuse.org/package/show/devel:libraries:c_c++/ftxui)
  * Good practices: documentation, tests, fuzzers, performance tests, automated CI, automated packaging, etc...
 
 ## Documentation
 
-- [Starter example project](https://github.com/ArthurSonzogni/ftxui-starter)
+- [Starter CMake](https://github.com/ArthurSonzogni/ftxui-starter)
+- [Starter Bazel](https://github.com/ArthurSonzogni/ftxui-bazel)
 - [Documentation](https://arthursonzogni.github.io/FTXUI/)
 - [Examples (WebAssembly)](https://arthursonzogni.github.io/FTXUI/examples/)
 - [Build using CMake](https://arthursonzogni.github.io/FTXUI/#build-cmake)
+- [Build using Bazel](https://arthursonzogni.github.io/FTXUI/#build-bazel)
 
 ## Example
 ~~~cpp
@@ -365,33 +374,62 @@ Several games using the FTXUI have been made during the Game Jam:
 - [smoothlife](https://github.com/cpp-best-practices/game_jam/blob/main/Jam1_April_2022/smoothlife.md)
 - [Consu](https://github.com/cpp-best-practices/game_jam/blob/main/Jam1_April_2022/consu.md)
 
-## Utilization
+## Build using CMake
 
 It is **highly** recommended to use CMake FetchContent to depend on FTXUI so you may specify which commit you would like to depend on.
 ```cmake
 include(FetchContent)
-
 FetchContent_Declare(ftxui
   GIT_REPOSITORY https://github.com/ArthurSonzogni/ftxui
-  GIT_TAG v6.1.8
+  GIT_TAG v6.1.9
 )
+FetchContent_MakeAvailable(ftxui)
 
-FetchContent_GetProperties(ftxui)
-if(NOT ftxui_POPULATED)
-  FetchContent_Populate(ftxui)
-  add_subdirectory(${ftxui_SOURCE_DIR} ${ftxui_BINARY_DIR} EXCLUDE_FROM_ALL)
-endif()
+target_link_libraries(your_target PRIVATE
+    # Chose a submodule
+    ftxui::component
+    ftxui::dom
+    ftxui::screen
+)
 ```
 
+# Build using Bazel
+
+**MODULE.bazel**
+```starlark
+bazel_dep(
+    name = "ftxui",
+    version = "v6.1.9",
+)
+```
+
+**BUILD.bazel**
+```starlark
+cc_binary(
+    name = "your_target",
+    srcs = ["your_source.cc"],
+    deps = [
+        "@ftxui//:ftxui_component",
+        "@ftxui//:ftxui_dom",
+        "@ftxui//:ftxui_screen",
+    ],
+)
+```
+
+
+# Build with something else:
 If you don't, FTXUI may be used from the following packages:
-- [bazel](...)
-- [vcpkg](https://vcpkgx.com/details.html?package=ftxui)
-- [Arch Linux PKGBUILD](https://aur.archlinux.org/packages/ftxui-git/).
-- [conan.io](https://conan.io/center/ftxui)
-- [openSUSE](https://build.opensuse.org/package/show/devel:libraries:c_c++/ftxui)
-- 
+- CMake [FetchContent]([https://bewagner.net/programming/2020/05/02/cmake-fetchcontent/](https://cmake.org/cmake/help/latest/module/FetchContent.html)) (preferred),
+- [Bazel](https://registry.bazel.build/modules/ftxui),
+- [vcpkg](https://vcpkg.link/ports/ftxui),
+- [Conan](https://conan.io/center/recipes/ftxui)
+- [Debian package](https://tracker.debian.org/pkg/ftxui),
+- [Ubuntu package](https://launchpad.net/ubuntu/+source/ftxui),
+- [Arch Linux](https://aur.archlinux.org/packages/ftxui/),
+- [OpenSUSE](https://build.opensuse.org/package/show/devel:libraries:c_c++/ftxui),
 [![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
 g++ . . . -lftxui-component -lftxui-dom -lftxui-screen . . .

bazel/ftxui.bzl

@@ -1,24 +1,7 @@
 # ftxui_common.bzl
 
 load("@rules_cc//cc:defs.bzl", "cc_library")
-
-def cpp17():
-    return select({
-        "@rules_cc//cc/compiler:msvc-cl": ["/std:c++17"],
-        "@rules_cc//cc/compiler:clang-cl": ["/std:c++17"],
-        "@rules_cc//cc/compiler:clang": ["-std=c++17"],
-        "@rules_cc//cc/compiler:gcc": ["-std=c++17"],
-        "//conditions:default": ["-std=c++17"],
-    })
-
-def cpp20():
-    return select({
-        "@rules_cc//cc/compiler:msvc-cl": ["/std:c++20"],
-        "@rules_cc//cc/compiler:clang-cl": ["/std:c++20"],
-        "@rules_cc//cc/compiler:clang": ["-std=c++20"],
-        "@rules_cc//cc/compiler:gcc": ["-std=c++20"],
-        "//conditions:default": ["-std=c++20"],
-    })
+load("@rules_cc//cc:defs.bzl", "cc_binary")
 
 # Microsoft terminal is a bit buggy ¯\_(ツ)_/¯ and MSVC uses bad defaults.
 def windows_copts():
@@ -45,7 +28,8 @@ def windows_copts():
       # This
       # - Replace missing font symbols by others.
       # - Reduce screen position pooling frequency to deals against a Microsoft
-      #   race condition. This was fixed in 2020, but clients never not updated.
+      #   race condition. This was fixed in 2020, but clients are still using
+      #   old versions.
       #   - https://github.com/microsoft/terminal/pull/7583
       #   - https://github.com/ArthurSonzogni/FTXUI/issues/136
       "-DFTXUI_MICROSOFT_TERMINAL_FALLBACK",
@@ -71,8 +55,8 @@ def pthread_linkopts():
 
 def ftxui_cc_library(
         name,
-        srcs,
-        hdrs,
+        srcs = [],
+        hdrs = [],
         linkopts = [],
         deps = []):
 
@@ -88,12 +72,13 @@ def ftxui_cc_library(
             "include",
             "src",
         ],
-        copts = cpp17() + windows_copts(),
+        copts = windows_copts(),
         visibility = ["//visibility:public"],
     )
 
 # Compile all the examples in the examples/ directory.
-# This is useful to check the Bazel is synchronized with CMake definitions.
+# This is useful to check the Bazel is always synchronized against CMake
+# definitions.
 def generate_examples():
     cpp_files = native.glob(["examples/**/*.cpp"])
 
@@ -107,9 +92,13 @@ def generate_examples():
         # Turn "examples/component/button.cpp" → "example_component_button"
         name = src.replace("/", "_").replace(".cpp", "")
 
-        native.cc_binary(
+        cc_binary(
             name = name,
             srcs = [src],
-            deps = ["//:component"],
-            copts = cpp20() + windows_copts(),
+            deps = [
+              ":component",
+              ":dom",
+              ":screen",
+            ],
+            copts = windows_copts(),
         )

doc/mainpage.md

@@ -81,7 +81,7 @@ include(FetchContent)
 set(FETCHCONTENT_UPDATES_DISCONNECTED TRUE)
 FetchContent_Declare(ftxui
   GIT_REPOSITORY https://github.com/ArthurSonzogni/ftxui
-  GIT_TAG main # Important: Specify a version or a commit hash here.
+  GIT_TAG 6.1.9
 )
 FetchContent_MakeAvailable(ftxui)
 
@@ -94,13 +94,33 @@ target_link_libraries(ftxui-starter
 )
 ```
 
-## Build
+### Using Bazel {#build-bazel}
 
-```bash
-mkdir build && cd build
-cmake ..
-make
-./main
+See [ftxui module](https://registry.bazel.build/modules/ftxui) from the Bazel
+Central Registry.
+
+See also this [starter](https://github.com/ArthurSonzogni/ftxui-bazel) project.
+
+**Module.bazel**
+```starlark
+bazel_dep(
+    name = "ftxui",
+    version = "6.1.9",
+)
+```
+
+**BUILD.bazel**
+```starlark
+cc_binary(
+    name = "main",
+    srcs = ["main.cpp"],
+    deps = [
+        # Choose one of the following:
+        "@ftxui//:dom",
+        "@ftxui//:screen",
+        "@ftxui//:component",
+    ],
+)
 ```
 
 # List of modules. {#modules}

src/ftxui/screen/terminal.cpp

@@ -48,25 +48,38 @@ Dimensions& FallbackSize() {
   return g_fallback_size;
 }
 
-const char* Safe(const char* c) {
-  return (c != nullptr) ? c : "";
-}
-
 bool Contains(const std::string& s, const char* key) {
   return s.find(key) != std::string::npos;
 }
 
+// https://github.com/gabime/spdlog/blob/885b5473e291833b148eeac3b7ce227e582cd88b/include/spdlog/details/os-inl.h#L566
+std::string getenv_safe(const char *field) {
+#if defined(_MSC_VER)
+#if defined(__cplusplus_winrt)
+  return std::string{};  // not supported under uwp
+#else
+  size_t len = 0;
+  char buf[1024];
+  bool ok = ::getenv_s(&len, buf, sizeof(buf), field) == 0;
+  return ok ? buf : std::string{};
+#endif
+#else  // revert to getenv
+  char *buf = ::getenv(field); // NOLINT(*-mt-unsafe)
+  return buf ? buf : std::string{};
+#endif
+}
+
 Terminal::Color ComputeColorSupport() {
 #if defined(__EMSCRIPTEN__)
   return Terminal::Color::TrueColor;
 #endif
 
-  std::string COLORTERM = Safe(std::getenv("COLORTERM"));  // NOLINT
+  std::string COLORTERM = getenv_safe("COLORTERM");
   if (Contains(COLORTERM, "24bit") || Contains(COLORTERM, "truecolor")) {
     return Terminal::Color::TrueColor;
   }
 
-  std::string TERM = Safe(std::getenv("TERM"));  // NOLINT
+  std::string TERM = getenv_safe("TERM");
   if (Contains(COLORTERM, "256") || Contains(TERM, "256")) {
     return Terminal::Color::Palette256;
   }

tools/test_bazel.sh

@@ -0,0 +1,18 @@
+# This script tests the project with different versions of Bazel and compilers
+# locally. This avoids waiting on the CI to run the tests.
+
+for ver in \
+  "6.0.0" \
+  "7.0.0" \
+  "8.0.0"
+do
+  for cc in \
+    "gcc" \
+    "clang"
+    do
+      echo "=== Testing with Bazel ${ver} with ${cc} ==="
+      USE_BAZEL_VERSION=${ver} CC=${cc} bazel clean --expunge
+      USE_BAZEL_VERSION=${ver} CC=${cc} bazel build //...
+      USE_BAZEL_VERSION=${ver} CC=${cc} bazel test //...
+    done
+  done