fix(tui): remove obsolete $NVIM detection #15791

Initially, we planned to set the NVIM environment variable to detect that
neovim is running in the neovim built-in terminal. At the time this code
was written, there was no way for a parent to set environment variables
for a program running in an embedded terminal. Later it was implemented in
 #12937, but the code to set the NVIM was not added. #11390 now uses ConPTY
instead of winpty when possible, so it is no longer necessary to force the
use of win32con even when running inside an embedded terminal. Therefore,
we now do not need this code.

1 files changed, 0 insertions, 9 deletions

diff --git a/src/nvim/os/tty.c b/src/nvim/os/tty.c
index c80ef99084..126b1b0044 100644
--- a/src/nvim/os/tty.c
+++ b/src/nvim/os/tty.c
@@ -23,15 +23,6 @@
 /// @param out_fd stdout file descriptor
 void os_tty_guess_term(const char **term, int out_fd)
 {
-  bool winpty = (os_getenv("NVIM") != NULL);
-
-  if (winpty) {
-    // Force TERM=win32con when running in winpty.
-    *term = "win32con";
-    uv_tty_set_vterm_state(UV_TTY_UNSUPPORTED);
-    return;
-  }
-
   bool conemu_ansi = strequal(os_getenv("ConEmuANSI"), "ON");
   bool vtp = false;