Fix errors.

Refactored the POSIX piped input handling to avoid redirecting stdin.
Instead, it now directly opens and reads from /dev/tty for keyboard input
when stdin is piped, allowing applications to process piped data while
still receiving interactive keyboard events.

This addresses the TODO comment in ScreenInteractive::InstallPipedInputHandling().

CHANGELOG.md

@@ -35,6 +35,8 @@ Next
   Thanks @HarryPehkonen for PR #1094.
 - Fix ScreenInteractive::FixedSize screen stomps on the preceding terminal
   output. Thanks @zozowell in #1064.
+- Fix vertical `ftxui::Slider`. The "up" key was previously decreasing the
+  value. Thanks @its-pablo in #1093 for reporting the issue.
 
 
 6.1.9 (2025-05-07)

CMakeLists.txt

@@ -178,8 +178,8 @@ include(cmake/ftxui_install.cmake)
 include(cmake/ftxui_package.cmake)
 include(cmake/ftxui_modules.cmake)
 
-add_subdirectory(doc)
 add_subdirectory(examples)
+add_subdirectory(doc)
 
 # You can generate ./examples_modules/ by running
 # ./tools/generate_examples_modules.sh

examples/CMakeLists.txt

@@ -17,10 +17,12 @@ add_subdirectory(dom)
 if (EMSCRIPTEN)
   get_property(EXAMPLES GLOBAL PROPERTY FTXUI::EXAMPLES)
   foreach(file
+      "index.css"
       "index.html"
       "index.mjs"
-      "index.css"
+      "run_webassembly.py"
-      "run_webassembly.py")
+      "sw.js"
+  )
     configure_file(${file} ${file})
   endforeach(file)
 endif()

examples/index.css

@@ -1,15 +1,19 @@
 @import url(https://fonts.googleapis.com/css?family=Khula:700);
 
+html {
+  --toc-width: 250px;
+}
+
 body {
-  background-color:#EEE;
+  background-color: #EEE;
-  padding:0px;
+  padding: 0px;
-  margin:0px;
+  margin: 0px;
   font-family: Khula, Helvetica, sans-serif;
   font-size: 130%;
 }
 
 .page {
-  max-width:1300px;
+  max-width: 1300px;
   margin: auto;
   padding: 10px;
 }
@@ -20,7 +24,7 @@ a {
   margin: 0 -.25rem;
   padding: 0 .25rem;
   transition: color .3s ease-in-out,
-              box-shadow .3s ease-in-out;
+    box-shadow .3s ease-in-out;
 }
 
 a:hover {
@@ -30,45 +34,48 @@ a:hover {
 
 h1 {
   text-decoration: underline;
-  width:100%;
+  width: 100%;
-  background-color: rgba(100,100,255,0.5);
+  background-color: rgba(100, 100, 255, 0.5);
   padding: 10px;
   margin: 0;
 }
 
 
 #selectExample {
-  flex:1;
+  flex: 1;
 }
 
-#selectExample, #selectExample option {
+#selectExample,
+#selectExample option {
   font-size: 16px;
   font-family: sans-serif;
   font-weight: 700;
   line-height: 1.3;
-  border:0px;
+  border: 0px;
   background-color: #bbb;
-  color:black;
+  color: black;
 }
 
 #selectExample:focus {
-  outline:none;
+  outline: none;
 }
 
 #terminal {
-  width:100%;
+  width: 100%;
   height 500px;
   height: calc(clamp(200px, 100vh - 300px, 900px));
   overflow: hidden;
-  border:none;
+  border: none;
-  background-color:black;
+  padding: 10px;
+  margin: 10px;
 }
 
 #terminalContainer {
   overflow: hidden;
   border-radius: 10px;
-  box-shadow: 0px 2px 10px 0px rgba(0,0,0,0.75),
+  box-shadow: 0px 2px 10px 0px rgba(0, 0, 0, 0.75),
-  0px 2px 80px 0px rgba(0,0,0,0.50);
+    0px 2px 80px 0px rgba(0, 0, 0, 0.50);
+  background-color: black;
 }
 
 .fakeButtons {
@@ -76,7 +83,7 @@ h1 {
   width: 10px;
   border-radius: 50%;
   border: 1px solid #000;
-  margin:6px;
+  margin: 6px;
   background-color: #ff3b47;
   border-color: #9d252b;
   display: inline-block;
@@ -95,13 +102,79 @@ h1 {
 }
 
 .fakeMenu {
-  display:flex;
+  display: flex;
   flex-direction: row;
-  width:100%;
+  width: 100%;
   box-sizing: border-box;
   height: 25px;
   background-color: #bbb;
-  color:black;
+  color: black;
   margin: 0 auto;
   overflow: hidden;
 }
+
+.toc-container {
+  position: fixed;
+  left: 0;
+  top: 0;
+  bottom: 0;
+  width: var(--toc-width);
+  background: white;
+  padding: 0;
+  overflow-y: auto;
+  overflow-x: hidden;
+  scrollbar-width: thin;
+}
+
+.toc-title {
+  font-weight: bold;
+  margin-bottom: 5px;
+  font-size: 0.9em;
+  color: #555;
+
+  position: sticky;
+  transition: position 1.0s ease-in-out;
+  top: 0;
+  z-index: 1;
+  padding: 20px;
+  margin: 0;
+
+  border-bottom: 1px solid #ddd;
+
+  /* Gradient background for the title */
+  background-color: #f0f0f0;
+}
+
+.toc-item {
+  padding: 3px 8px;
+  margin: 0;
+  cursor: pointer;
+  font-size: 0.85em;
+  border-radius: 3px;
+  transition: background 0.2s;
+}
+
+.toc-item:hover {
+  background: #f0f0f0;
+}
+
+.toc-item.selected {
+  background: #e0e0e0;
+  font-weight: bold;
+}
+
+@media (max-width: 1024px) {
+  .toc-container {
+    display: none;
+  }
+
+  .page {
+    margin-left: 0;
+  }
+}
+
+@media (min-width: 1025px) {
+  .page {
+    margin-left: calc(var(--toc-width) + 20px);
+  }
+}

examples/index.html

@@ -9,13 +9,18 @@
     <script type="module" src="index.mjs"></script>
   </head>
   <body>
+    <div class="toc-container">
+      <div class="toc-list"></div>
+    </div>
     <script id="example_script"></script>
 
     <div class="page">
       <p>
         <a href="https://github.com/ArthurSonzogni/FTXUI">FTXUI</a> is a simple
         functional C++ library for terminal user interface. <br/>
-        This showcases the: <a href="https://github.com/ArthurSonzogni/FTXUI/tree/master/examples">./example/</a> folder. <br/>
+        This showcases the: <a
+          href="https://github.com/ArthurSonzogni/FTXUI/tree/master/examples">./example/</a>
+        folder. See <a id="source">source</a>.
       </p>
 
       <div id="terminalContainer">

examples/index.mjs

@@ -92,6 +92,69 @@ window.Module = {
   },
 };
 
+const source = document.querySelector("#source");
+source.href = "https://github.com/ArthurSonzogni/FTXUI/blob/main/examples/" + example + ".cpp";
+
 const words = example.split('/')
 words[1] = "ftxui_example_" + words[1] + ".js"
 document.querySelector("#example_script").src = words.join('/');
+
+
+// Table of Contents (TOC) for quick navigation.
+
+// Get select element
+const selectEl = document.querySelector('select#selectExample');
+if (!selectEl) {
+  console.error('select#selectExample not found');
+} else {
+  // Get TOC container
+  const tocContainer = document.querySelector('.toc-container');
+  const tocList = tocContainer.querySelector('.toc-list');
+
+  // Group options by directory
+  const groupedOptions = Array.from(selectEl.options).reduce((acc, option) => {
+    const [dir, file] = option.text.split('/');
+    if (!acc[dir]) {
+      acc[dir] = [];
+    }
+    acc[dir].push({ option, file });
+    return acc;
+  }, {});
+
+  // Generate TOC items
+  for (const dir in groupedOptions) {
+    const dirContainer = document.createElement('div');
+
+    const dirHeader = document.createElement('div');
+    dirHeader.textContent = dir;
+    dirHeader.className = 'toc-title';
+    dirContainer.appendChild(dirHeader);
+
+    groupedOptions[dir].forEach(({ option, file }) => {
+      const tocItem = document.createElement('div');
+      tocItem.textContent = file;
+      tocItem.className = 'toc-item';
+
+      if (selectEl.options[selectEl.selectedIndex].value === option.value) {
+        tocItem.classList.add('selected');
+      }
+
+      // Click handler
+      tocItem.addEventListener('click', () => {
+        for(let i=0; i<selectEl.options.length; ++i) {
+          if (selectEl.options[i].value == option.value) {
+            selectEl.selectedIndex = i;
+            break;
+          }
+        }
+
+        history.pushState({}, "", "?file=" + option.value);
+        location.reload();
+      });
+
+      dirContainer.appendChild(tocItem);
+    });
+
+    tocList.appendChild(dirContainer);
+  }
+}''

include/ftxui/component/receiver.hpp

@@ -4,7 +4,6 @@
 #ifndef FTXUI_COMPONENT_RECEIVER_HPP_
 #define FTXUI_COMPONENT_RECEIVER_HPP_
 
-#include <ftxui/util/warn_windows_macro.h>
 #include <algorithm>           // for copy, max
 #include <atomic>              // for atomic, __atomic_base
 #include <condition_variable>  // for condition_variable
@@ -12,6 +11,7 @@
 #include <mutex>               // for mutex, unique_lock
 #include <queue>               // for queue
 #include <utility>             // for move
+#include "ftxui/util/warn_windows_macro.hpp"
 
 namespace ftxui {
 

include/ftxui/util/warn_windows_macro.hpp

@@ -2,8 +2,8 @@
 // Use of this source code is governed by the MIT license that can be found in
 // the LICENSE file.
 
-#ifndef FTXUI_UTIL_WARN_WINDOWS_MACRO_H_
+#ifndef FTXUI_UTIL_WARN_WINDOWS_MACRO_HPP_
-#define FTXUI_UTIL_WARN_WINDOWS_MACRO_H_
+#define FTXUI_UTIL_WARN_WINDOWS_MACRO_HPP_
 
 #ifdef min
 #error \
@@ -15,4 +15,4 @@
     "The macro 'max' is defined, which conflicts with the standard C++ library and FTXUI. This is often caused by including <windows.h>. To fix this, add '#define NOMINMAX' before including <windows.h>, or pass '/DNOMINMAX' as a compiler flag."
 #endif
 
-#endif  // FTXUI_UTIL_WARN_WINDOWS_MACRO_H_
+#endif  // FTXUI_UTIL_WARN_WINDOWS_MACRO_HPP_

src/ftxui/component/screen_interactive.cpp

@@ -115,7 +115,7 @@ void ftxui_on_resize(int columns, int rows) {
 int CheckStdinReady(int fd) {
   timeval tv = {0, 0};  // NOLINT
   fd_set fds;
-  FD_ZERO(&fds);                                          // NOLINT
+  FD_ZERO(&fds);                                // NOLINT
   FD_SET(fd, &fds);                             // NOLINT
   select(fd + 1, &fds, nullptr, nullptr, &tv);  // NOLINT
   return FD_ISSET(fd, &fds);                    // NOLINT
@@ -679,7 +679,7 @@ void ScreenInteractive::Install() {
 }
 
 void ScreenInteractive::InstallPipedInputHandling() {
-  tty_fd_ = fileno(stdin);  // NOLINT
+  tty_fd_ = STDIN_FILENO;
 #if !defined(_WIN32) && !defined(__EMSCRIPTEN__)
   // Handle piped input redirection if explicitly enabled by the application.
   // This allows applications to read data from stdin while still receiving
@@ -689,7 +689,7 @@ void ScreenInteractive::InstallPipedInputHandling() {
   }
 
   // If stdin is a terminal, we don't need to open /dev/tty.
-  if (isatty(fileno(stdin))) {
+  if (isatty(STDIN_FILENO)) {
     return;
   }
 
@@ -697,7 +697,7 @@ void ScreenInteractive::InstallPipedInputHandling() {
   tty_fd_ = open("/dev/tty", O_RDONLY);
   if (tty_fd_ < 0) {
     // Failed to open /dev/tty (containers, headless systems, etc.)
-    tty_fd_ = fileno(stdin);  // Fallback to stdin.
+    tty_fd_ = STDIN_FILENO;  // Fallback to stdin.
     return;
   }
 

src/ftxui/component/screen_interactive_piped_input_test.cpp

@@ -1,11 +1,11 @@
 // 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.
-#include <gtest/gtest.h>
-#include <unistd.h>
 #include <fcntl.h>
-#include <cstdio>
+#include <gtest/gtest.h>
 #include <sys/stat.h>
+#include <unistd.h>
+#include <cstdio>
 
 #include "ftxui/component/component.hpp"
 #include "ftxui/component/screen_interactive.hpp"
@@ -47,7 +47,7 @@ class PipedInputTest : public ::testing::Test {
   void WriteToPipedStdin(const std::string& data) {
     if (piped_stdin_setup_) {
       write(pipe_fds_[1], data.c_str(), data.length());
-      close(pipe_fds_[1]); // Close write end to signal EOF
+      close(pipe_fds_[1]);  // Close write end to signal EOF
     }
   }
 
@@ -94,10 +94,10 @@ TEST_F(PipedInputTest, ExplicitlyDisabled) {
   WriteToPipedStdin("test data\n");
 
   screen.Install();
-  
+
   // Stdin should still be the pipe since feature is disabled
   EXPECT_FALSE(isatty(STDIN_FILENO));
-  
+
   screen.Uninstall();
 }
 
@@ -107,7 +107,7 @@ TEST_F(PipedInputTest, ExplicitlyEnabled) {
   }
 
   auto screen = ScreenInteractive::TerminalOutput();
-  screen.HandlePipedInput(true); // Explicitly enable
+  screen.HandlePipedInput(true);  // Explicitly enable
   auto component = Renderer([] { return text("test"); });
 
   SetupPipedStdin();
@@ -117,12 +117,12 @@ TEST_F(PipedInputTest, ExplicitlyEnabled) {
   EXPECT_FALSE(isatty(STDIN_FILENO));
 
   screen.Install();
-  
+
   // After install with piped input handling: stdin should be redirected to tty
   EXPECT_TRUE(isatty(STDIN_FILENO));
-  
+
   screen.Uninstall();
-  
+
   // After uninstall: stdin should be restored to original state
   // Note: This will be the pipe we set up, so it should be non-tty
   EXPECT_FALSE(isatty(STDIN_FILENO));
@@ -137,12 +137,12 @@ TEST_F(PipedInputTest, NormalStdinUnchanged) {
   bool original_isatty = isatty(STDIN_FILENO);
 
   screen.Install();
-  
+
   // Stdin should remain unchanged
   EXPECT_EQ(original_isatty, isatty(STDIN_FILENO));
-  
+
   screen.Uninstall();
-  
+
   // Stdin should still be unchanged
   EXPECT_EQ(original_isatty, isatty(STDIN_FILENO));
 }
@@ -173,12 +173,12 @@ TEST_F(PipedInputTest, MultipleInstallUninstallCycles) {
 
 TEST_F(PipedInputTest, HandlePipedInputMethodBehavior) {
   auto screen = ScreenInteractive::TerminalOutput();
-  
+
   // Test method can be called multiple times
   screen.HandlePipedInput(true);
   screen.HandlePipedInput(false);
   screen.HandlePipedInput(true);
-  
+
   // Should be enabled after last call
   SetupPipedStdin();
   WriteToPipedStdin("test data\n");
@@ -191,7 +191,8 @@ TEST_F(PipedInputTest, HandlePipedInputMethodBehavior) {
 }
 
 // Test the graceful fallback when /dev/tty is not available
-// This test simulates environments like containers where /dev/tty might not exist
+// This test simulates environments like containers where /dev/tty might not
+// exist
 TEST_F(PipedInputTest, GracefulFallbackWhenTtyUnavailable) {
   auto screen = ScreenInteractive::TerminalOutput();
   auto component = Renderer([] { return text("test"); });
@@ -199,22 +200,23 @@ TEST_F(PipedInputTest, GracefulFallbackWhenTtyUnavailable) {
   SetupPipedStdin();
   WriteToPipedStdin("test data\n");
 
-  // This test doesn't directly mock /dev/tty unavailability since that's hard to do
+  // This test doesn't directly mock /dev/tty unavailability since that's hard
-  // in a unit test environment, but the code path handles freopen() failure gracefully
+  // to do in a unit test environment, but the code path handles freopen()
+  // failure gracefully
   screen.Install();
-  
+
   // The behavior depends on whether /dev/tty is available
   // If available, stdin gets redirected; if not, it remains piped
   // Both behaviors are correct
-  
+
   screen.Uninstall();
-  
+
   // After uninstall, stdin should be restored
-  EXPECT_FALSE(isatty(STDIN_FILENO)); // Should still be our test pipe
+  EXPECT_FALSE(isatty(STDIN_FILENO));  // Should still be our test pipe
 }
 
 }  // namespace
 
 }  // namespace ftxui
 
-#endif  // !defined(_WIN32) && !defined(__EMSCRIPTEN__)
+#endif  // !defined(_WIN32) && !defined(__EMSCRIPTEN__)

src/ftxui/component/slider.cpp

@@ -33,6 +33,20 @@ Decorator flexDirection(Direction direction) {
   return xflex;  // NOT_REACHED()
 }
 
+Direction Opposite(Direction d) {
+  switch (d) {
+    case Direction::Up:
+      return Direction::Down;
+    case Direction::Down:
+      return Direction::Up;
+    case Direction::Left:
+      return Direction::Right;
+    case Direction::Right:
+      return Direction::Left;
+  }
+  return d;  // NOT_REACHED()
+}
+
 template <class T>
 class SliderBase : public SliderOption<T>, public ComponentBase {
  public:
@@ -47,59 +61,15 @@ class SliderBase : public SliderOption<T>, public ComponentBase {
            flexDirection(this->direction) | reflect(gauge_box_) | gauge_color;
   }
 
-  void OnLeft() {
+  void OnDirection(Direction pressed) {
-    switch (this->direction) {
+    if (pressed == this->direction) {
-      case Direction::Right:
+      this->value() += this->increment();
-        this->value() -= this->increment();
+      return;
-        break;
-      case Direction::Left:
-        this->value() += this->increment();
-        break;
-      case Direction::Up:
-      case Direction::Down:
-        break;
     }
-  }
 
-  void OnRight() {
+    if (pressed == Opposite(this->direction)) {
-    switch (this->direction) {
+      this->value() -= this->increment();
-      case Direction::Right:
+      return;
-        this->value() += this->increment();
-        break;
-      case Direction::Left:
-        this->value() -= this->increment();
-        break;
-      case Direction::Up:
-      case Direction::Down:
-        break;
-    }
-  }
-
-  void OnUp() {
-    switch (this->direction) {
-      case Direction::Up:
-        this->value() -= this->increment();
-        break;
-      case Direction::Down:
-        this->value() += this->increment();
-        break;
-      case Direction::Left:
-      case Direction::Right:
-        break;
-    }
-  }
-
-  void OnDown() {
-    switch (this->direction) {
-      case Direction::Down:
-        this->value() += this->increment();
-        break;
-      case Direction::Up:
-        this->value() -= this->increment();
-        break;
-      case Direction::Left:
-      case Direction::Right:
-        break;
     }
   }
 
@@ -110,16 +80,16 @@ class SliderBase : public SliderOption<T>, public ComponentBase {
 
     T old_value = this->value();
     if (event == Event::ArrowLeft || event == Event::Character('h')) {
-      OnLeft();
+      OnDirection(Direction::Left);
     }
     if (event == Event::ArrowRight || event == Event::Character('l')) {
-      OnRight();
+      OnDirection(Direction::Right);
     }
     if (event == Event::ArrowUp || event == Event::Character('k')) {
-      OnDown();
+      OnDirection(Direction::Up);
     }
     if (event == Event::ArrowDown || event == Event::Character('j')) {
-      OnUp();
+      OnDirection(Direction::Down);
     }
 
     this->value() = std::max(this->min(), std::min(this->max(), this->value()));