Extend IO#tty? to recognize Windows PTYs

ext/io/console/console.c

@@ -1914,6 +1914,103 @@ console_ttyname(VALUE io)
 # define console_ttyname rb_f_notimplement
 #endif
 
+typedef enum {
+    platform_default,
+#if defined _WIN32 || defined __CYGWIN__
+    platform_cygwin,
+    platform_msys,
+#endif
+    platform_any,
+
+    platform_default_bit = 1U << platform_default,
+#if defined _WIN32 || defined __CYGWIN__
+    platform_cygwin_bit = 1U << platform_cygwin,
+    platform_msys_bit = 1U << platform_msys,
+#endif
+    platform_any_bit = (1U << platform_any) - 1 /* all bits */
+} console_platform_t;
+
+/*
+ * call-seq:
+ *   io.tty?([mode, ...])	-> true or false
+ *
+ * Returns +true+ if the stream is associated with a terminal device (tty),
+ * +false+ otherwise.
+ *
+ * If one or more +type+s are given, returns +true+ if the stream is
+ * associated with any of the specified tty types.
+ *
+ * - +nil+ : Returns the result of the default tty check, as if no type were
+ *   given.  It can be combined with other types.
+ * - +:any+ : Returns +true+ for any known kind of tty, including the
+ *   default tty.
+ * - +:cygwin+ : Returns +true+ for cygwin tty, on Windows.
+ * - +:msys+ : Returns +true+ for msys2 tty, on Windows.
+ */
+static VALUE
+console_platform_tty_p(int argc, VALUE *argv, VALUE io)
+{
+    VALUE ret = Qfalse;
+    int mode = 0;
+
+    if (argc > 0) {
+	int i;
+	for (i = 0; i < argc; ++i) {
+	    VALUE m = argv[i];
+	    if (NIL_P(m)) {
+		mode |= platform_default_bit;
+		continue;
+	    }
+	    Check_Type(m, T_SYMBOL);
+	    if (m == ID2SYM(rb_intern("any"))) {
+		mode |= platform_any_bit;
+	    }
+#if defined _WIN32 || defined __CYGWIN__
+	    else if (m == ID2SYM(rb_intern("cygwin"))) {
+		mode |= platform_cygwin_bit;
+	    }
+	    else if (m == ID2SYM(rb_intern("msys"))) {
+		mode |= platform_msys_bit;
+	    }
+#endif
+	    else {
+		rb_raise(rb_eArgError, "unknown tty type: %+" PRIsVALUE, m);
+	    }
+	}
+    }
+    if ((mode & platform_default_bit) || (mode == 0)) {
+	ret = rb_call_super(0, 0);
+    }
+    if ((mode & ~platform_default_bit) && !RTEST(ret)) {
+#if defined _WIN32 || defined __CYGWIN__
+	if (mode & (platform_cygwin_bit | platform_msys_bit)) {
+	    struct {
+		FILE_NAME_INFO info;
+		WCHAR rest[MAX_PATH];
+	    } buffer;
+
+	    HANDLE h = (HANDLE)rb_w32_get_osfhandle(GetReadFD(io));
+	    if ((GetFileType(h) == FILE_TYPE_PIPE) &&
+		GetFileInformationByHandleEx(h, FileNameInfo, &buffer, sizeof(buffer))) {
+		WCHAR *const name = buffer.info.FileName;
+		DWORD len = buffer.info.FileNameLength / sizeof(WCHAR);
+		name[len] = L'\0';
+# define tty_pipe_p(type) \
+		(memcmp(name, L"\\" #type "-", sizeof(L"\\" #type)) == 0 && \
+		 wcsstr(&name[rb_strlen_lit("\\" #type "-")], L"-pty") != NULL)
+		if (!ret && (mode & platform_cygwin_bit)) {
+		    ret = tty_pipe_p(cygwin);
+		}
+		if (!ret && (mode & platform_msys_bit)) {
+		    ret = tty_pipe_p(msys);
+		}
+	    }
+	}
+#endif
+    }
+    return ret;
+}
+
 /*
  * IO console methods
  */
@@ -1982,6 +2079,21 @@ InitVM_console(void)
     rb_define_method(rb_cIO, "check_winsize_changed", console_check_winsize_changed, 0);
     rb_define_method(rb_cIO, "getpass", console_getpass, -1);
     rb_define_method(rb_cIO, "ttyname", console_ttyname, 0);
+    {
+	/* :stopdoc: */
+	VALUE platform = rb_define_module_under(rb_cIO, "platform_tty");
+	/* :startdoc: */
+	{
+	    VALUE rb_cIO = platform;
+	    rb_define_method(rb_cIO, "tty?", console_platform_tty_p, -1);
+	    rb_define_method(rb_cIO, "isatty", console_platform_tty_p, -1);
+	}
+#ifdef HAVE_RB_PREPEND_MODULE
+	rb_prepend_module(rb_cIO, platform);
+#else
+	rb_funcall(rb_cIO, rb_intern_const("prepend"), 1, platform);
+#endif
+    }
     rb_define_singleton_method(rb_cIO, "console", console_dev, -1);
     {
 	/* :nodoc: */

ext/io/console/extconf.rb

@@ -23,6 +23,7 @@
 hdr = nil
 case
 when macro_defined?("_WIN32", "")
+  win32 = true
   # rb_w32_map_errno: 1.8.7
   vk_header = File.exist?("#$srcdir/win32_vk.list") ? "chksum" : "inc"
   vk_header = "#{'{$(srcdir)}' if $nmake == ?m}win32_vk.#{vk_header}"
@@ -47,7 +48,8 @@
   elsif have_func("rb_scheduler_timeout") # Ruby 3.0 (internal)
     have_func("rb_io_wait") # Ruby 3.0
   end
-  have_func("ttyname_r") or have_func("ttyname")
+  win32 or have_func("ttyname_r") or have_func("ttyname")
+  have_func("rb_prepend_module") # not exported by TruffleRuby
   create_makefile("io/console") {|conf|
     conf << "\n""VK_HEADER = #{vk_header}\n"
   }

test/io/console/test_io_console.rb

@@ -60,9 +60,37 @@ def test_bad_keyword
       end
     end
   end
+
+  TTY_ENHANCED = IO.instance_method(:tty?).arity != 0
+
+  def test_tty?
+    pend "not supported" unless TTY_ENHANCED
+
+    tty = STDIN.tty?(:any)
+    assert_include([true, false], tty)
+    assert_equal(tty, STDIN.tty?(:any, :any))
+    assert_equal(tty, STDIN.tty?(nil, :any))
+    assert_equal(STDIN.tty?, STDIN.tty?(nil))
+  end
+
+  def test_tty_non_tty
+    pend "not supported" unless TTY_ENHANCED
+
+    File.open(IO::NULL) do |f|
+      assert_not_predicate(f, :tty?)
+      assert_not_operator(f, :tty?, :any)
+      assert_not_operator(f, :tty?, nil)
+      assert_not_send([f, :tty?, :any, :any])
+      assert_not_send([f, :tty?, nil, :any])
+
+      assert_raise(TypeError) {f.tty?("any")}
+      assert_raise(ArgumentError) {f.tty?(:unknown)}
+    end
+  end
 end
 
-defined?(PTY) and defined?(IO.console) and TestIO_Console.class_eval do
+defined?(PTY) and defined?(IO.console) and \
+class TestIO_Console
   Bug6116 = '[ruby-dev:45309]'
 
   def test_raw
@@ -242,6 +270,21 @@ def test_setecho2
     }
   end
 
+  def test_tty_on_pty
+    pend "not supported" unless TTY_ENHANCED
+
+    helper {|_, s|
+      assert_predicate(s, :tty?)
+      assert_operator(s, :tty?, :any)
+      assert_operator(s, :tty?, nil)
+      assert_send([s, :tty?, :any, :any])
+      assert_send([s, :tty?, nil, :any])
+
+      assert_raise(TypeError) {s.tty?("any")}
+      assert_raise(ArgumentError) {s.tty?(:unknown)}
+    }
+  end
+
   def test_getpass
     run_pty("p IO.console.getpass('> ')") do |r, w|
       assert_equal("> ", r.readpartial(10))
@@ -495,66 +538,65 @@ def run_pty(src, n = 1)
   end
 end
 
-defined?(IO.console) and TestIO_Console.class_eval do
-  if IO.console
-    def test_get_winsize_console
-      s = IO.console.winsize
-      assert_kind_of(Array, s)
-      assert_equal(2, s.size)
-      assert_kind_of(Integer, s[0])
-      assert_kind_of(Integer, s[1])
-    end
+defined?(IO.console) and IO.console and \
+class TestIO_Console
+  def test_get_winsize_console
+    s = IO.console.winsize
+    assert_kind_of(Array, s)
+    assert_equal(2, s.size)
+    assert_kind_of(Integer, s[0])
+    assert_kind_of(Integer, s[1])
+  end
 
-    def test_set_winsize_console
-      set_winsize_setup
-      s = IO.console.winsize
-      assert_nothing_raised(TypeError) {IO.console.winsize = s}
-      bug = '[ruby-core:82741] [Bug #13888]'
-      begin
-        IO.console.winsize = [s[0], s[1]+1]
-        assert_equal([s[0], s[1]+1], IO.console.winsize, bug)
-      rescue Errno::EINVAL    # Error if run on an actual console.
-      else
-        IO.console.winsize = s
-        assert_equal(s, IO.console.winsize, bug)
-      end
-    ensure
-      set_winsize_teardown
+  def test_set_winsize_console
+    set_winsize_setup
+    s = IO.console.winsize
+    assert_nothing_raised(TypeError) {IO.console.winsize = s}
+    bug = '[ruby-core:82741] [Bug #13888]'
+    begin
+      IO.console.winsize = [s[0], s[1]+1]
+      assert_equal([s[0], s[1]+1], IO.console.winsize, bug)
+    rescue Errno::EINVAL    # Error if run on an actual console.
+    else
+      IO.console.winsize = s
+      assert_equal(s, IO.console.winsize, bug)
     end
+  ensure
+    set_winsize_teardown
+  end
 
-    def test_close
-      IO.console.close
-      assert_kind_of(IO, IO.console)
-      assert_nothing_raised(IOError) {IO.console.fileno}
+  def test_close
+    IO.console.close
+    assert_kind_of(IO, IO.console)
+    assert_nothing_raised(IOError) {IO.console.fileno}
 
-      IO.console(:close)
-      assert(IO.console(:tty?))
-    ensure
-      IO.console(:close)
-    end
+    IO.console(:close)
+    assert(IO.console(:tty?))
+  ensure
+    IO.console(:close)
+  end
 
-    def test_console_kw
-      io = IO.console(:clone, freeze: true)
-      io.close
-      assert_kind_of(IO, io)
-    end
+  def test_console_kw
+    io = IO.console(:clone, freeze: true)
+    io.close
+    assert_kind_of(IO, io)
+  end
 
-    def test_sync
-      assert(IO.console.sync, "console should be unbuffered")
-    ensure
-      IO.console(:close)
-    end
+  def test_sync
+    assert(IO.console.sync, "console should be unbuffered")
+  ensure
+    IO.console(:close)
+  end
 
-    def test_getch_timeout
-      assert_nil(IO.console.getch(intr: true, time: 0.1, min: 0))
-    end
+  def test_getch_timeout
+    assert_nil(IO.console.getch(intr: true, time: 0.1, min: 0))
+  end
 
-    def test_ttyname
-      return unless IO.method_defined?(:ttyname)
-      ttyname = IO.console.ttyname
-      assert_not_nil(ttyname)
-      File.open(ttyname) {|f| assert_predicate(f, :tty?)}
-    end
+  def test_ttyname
+    return unless IO.method_defined?(:ttyname)
+    ttyname = IO.console.ttyname
+    assert_not_nil(ttyname)
+    File.open(ttyname) {|f| assert_predicate(f, :tty?)}
   end
 
   case
@@ -563,6 +605,8 @@ def test_ttyname
   when !(rubyw = RbConfig::CONFIG["RUBYW_INSTALL_NAME"]).empty?
     dir, base = File.split(EnvUtil.rubybin)
     noctty = [File.join(dir, base.sub(RUBY_ENGINE, rubyw))]
+  else
+    rubyw = nil
   end
 
   if noctty
@@ -605,8 +649,8 @@ def test_noctty
   end
 end
 
-defined?(IO.console) and IO.console and IO.console.respond_to?(:pressed?) and
-  TestIO_Console.class_eval do
+defined?(IO.console) and IO.console and IO.console.respond_to?(:pressed?) and \
+class TestIO_Console
   def test_pressed_valid
     assert_include([true, false], IO.console.pressed?("HOME"))
     assert_include([true, false], IO.console.pressed?(:"HOME"))
@@ -620,7 +664,7 @@ def test_pressed_invalid
   end
 end
 
-TestIO_Console.class_eval do
+class TestIO_Console
   def test_stringio_getch
     assert_ruby_status %w"--disable=gems -rstringio -rio/console", %q{
       abort unless StringIO.method_defined?(:getch)