Remove tty check from table component

Check for tty should be done in the application and passed to the table.
Replace tty check with explicit setting for colored output.

Relates to GothenburgBitFactory/timewarrior#727 GothenburgBitFactory/timewarrior#730

Signed-off-by: Thomas Lauf <thomas.lauf@tngtech.com>

Author: lauft

src/Table.cpp

@@ -100,13 +100,7 @@ void Table::set (int row, int col, const Color color)
 std::string Table::render ()
 {
   // Piped output disables color, unless overridden.
-  if (! _forceColor &&
-#ifdef _WIN32
-      ! _isatty(_fileno(stdout))
-#else
-      ! isatty (STDOUT_FILENO)
-#endif
-      )
+  if (! _with_color)
   {
     _header     = Color ("");
     _odd        = Color ("");

src/Table.h

@@ -1,6 +1,6 @@
 ////////////////////////////////////////////////////////////////////////////////
 //
-// Copyright 2016 - 2017, 2019 - 2021, 2023, Gothenburg Bit Factory.
+// Copyright 2016 - 2017, 2019 - 2021, 2023, 2025 Gothenburg Bit Factory.
 //
 // Permission is hereby granted, free of charge, to any person obtaining a copy
 // of this software and associated documentation files (the "Software"), to deal
@@ -52,6 +52,7 @@ class Table
   void forceColor ()                   { _forceColor = true;         }
   void obfuscate ()                    { _obfuscate = true;          }
   void underlineHeaders ()             { _underline_headers = true;  }
+  void withColor (bool with_color)     { _with_color = with_color;   }
   int lines ()                         { return _lines;              }
   int rows ()                          { return (int) _data.size (); }
 
@@ -90,7 +91,8 @@ class Table
   Color                                   _extra_even        {0};
   int                                     _truncate_lines    {0};
   int                                     _truncate_rows     {0};
-  bool                                    _forceColor        {false};
+  bool                                    _forceColor        {false}; // TODO: remove once TW and TI have switched
+  bool                                    _with_color        {true};
   bool                                    _obfuscate         {false};
   bool                                    _underline_headers {false};
   int                                     _lines             {0};

test/table.t.cpp

@@ -31,7 +31,7 @@
 ////////////////////////////////////////////////////////////////////////////////
 int main (int, char**)
 {
-  UnitTest t (1);
+  UnitTest t (3);
 
   try
   {
@@ -75,6 +75,25 @@ int main (int, char**)
 
     std::cout << t1.render ();
     t.ok (t1.lines () > 4, "Table::lines > 4");
+    
+    // Test color behavior - with color enabled (default)
+    Table t3;
+    t3.width (80);
+    t3.add ("Header", true);
+    row = t3.addRow ();
+    t3.set (row, 0, "cell with color", single_cell);
+    std::string colored_output = t3.render ();
+    t.ok (colored_output.find("\033[") != std::string::npos, "Colored output contains ANSI escape codes");
+    
+    // Test color behavior - with color disabled
+    Table t4;
+    t4.width (80);
+    t4.withColor (false);  // Disable color
+    t4.add ("Header", true);
+    row = t4.addRow ();
+    t4.set (row, 0, "cell without color", single_cell);
+    std::string uncolored_output = t4.render ();
+    t.ok (uncolored_output.find("\033[") == std::string::npos, "Uncolored output does not contain ANSI escape codes");
 
     // Chessboard example
     Table t2;