Remove POSIX 'cpoptions': '.'

runtime/doc/options.txt

@@ -1952,11 +1952,6 @@ A jump table for the options with a short description can be found at |Q_op|.
 			   '\' included: "/[ \-]"  finds <Space>, '\' and '-'
 			   '\' excluded: "/[ \-]"  finds <Space> and '-'
 			Also see |cpo-l|.
-								*cpo-.*
-		.	The ":chdir" and ":cd" commands fail if the current
-			buffer is modified, unless ! is used.  Vim doesn't
-			need this, since it remembers the full path of an
-			opened file.
 
 						*'cryptmethod'* *'cm'*
 'cryptmethod'		Removed. |vim-differences| {Nvim}

src/nvim/ex_docmd.c

@@ -6834,12 +6834,6 @@ void ex_cd(exarg_T *eap)
   {
     if (allbuf_locked())
       return;
-    if (vim_strchr(p_cpo, CPO_CHDIR) != NULL && curbufIsChanged()
-        && !eap->forceit) {
-      EMSG(_(
-              "E747: Cannot change directory, buffer is modified (add ! to override)"));
-      return;
-    }
 
     /* ":cd -": Change to previous directory */
     if (STRCMP(new_dir, "-") == 0) {

src/nvim/option_defs.h

@@ -130,14 +130,13 @@
 #define CPO_REGAPPEND   '>'     /* insert NL when appending to a register */
 /* POSIX flags */
 #define CPO_BACKSL      '\\'    /* \ is not special in [] */
-#define CPO_CHDIR       '.'     /* don't chdir if buffer is modified */
 #define CPO_SCOLON      ';'     /* using "," and ";" will skip over char if
                                  * cursor would not move */
 /* default values for Vim, Vi and POSIX */
 #define CPO_VIM         "aABceFs"
 #define CPO_VI          "aAbBcCdDeEfFiIJkKlLmMnoOpPqrRsStuvWxXyZ$!%+<>;"
 #define CPO_ALL \
-  "aAbBcCdDeEfFiIJkKlLmMnoOpPqrRsStuvWxXyZ$!%+<>\\.;"
+  "aAbBcCdDeEfFiIJkKlLmMnoOpPqrRsStuvWxXyZ$!%+<>\\;"
 
 /* characters for p_ww option: */
 #define WW_ALL          "bshl<>[],~"