Remove POSIX 'cpoptions': '{'

runtime/doc/options.txt

@@ -1959,9 +1959,6 @@ A jump table for the options with a short description can be found at |Q_op|.
 								*cpo-/*
 		/	When "%" is used as the replacement string in a |:s|
 			command, use the previous replacement string. |:s%|
-								*cpo-{*
-		{	The |{| and |}| commands also stop at a "{" character
-			at the start of a line.
 								*cpo-.*
 		.	The ":chdir" and ":cd" commands fail if the current
 			buffer is modified, unless ! is used.  Vim doesn't

src/nvim/option_defs.h

@@ -129,7 +129,6 @@
 #define CPO_SPECI       '<'     /* don't recognize <> in mappings */
 #define CPO_REGAPPEND   '>'     /* insert NL when appending to a register */
 /* POSIX flags */
-#define CPO_PARA        '{'     /* "{" is also a paragraph boundary */
 #define CPO_TSIZE       '|'     /* $LINES and $COLUMNS overrule term size */
 #define CPO_PRESERVE    '&'     /* keep swap file after :preserve */
 #define CPO_SUBPERCENT  '/'     /* % in :s string uses previous one */
@@ -141,7 +140,7 @@
 #define CPO_VIM         "aABceFs"
 #define CPO_VI          "aAbBcCdDeEfFiIJkKlLmMnoOpPqrRsStuvWxXyZ$!%+<>;"
 #define CPO_ALL \
-  "aAbBcCdDeEfFiIJkKlLmMnoOpPqrRsStuvWxXyZ$!%+<>{|&/\\.;"
+  "aAbBcCdDeEfFiIJkKlLmMnoOpPqrRsStuvWxXyZ$!%+<>|&/\\.;"
 
 /* characters for p_ww option: */
 #define WW_ALL          "bshl<>[],~"

src/nvim/search.c

@@ -2199,7 +2199,6 @@ findpar (
   linenr_T curr;
   bool did_skip;            /* true after separating lines have been skipped */
   bool first;               /* true on first line */
-  int posix = (vim_strchr(p_cpo, CPO_PARA) != NULL);
   linenr_T fold_first;      /* first line of a closed fold */
   linenr_T fold_last;       /* last line of a closed fold */
   bool fold_skipped;        /* true if a closed fold was skipped this
@@ -2220,12 +2219,7 @@ findpar (
         fold_skipped = true;
       }
 
-      /* POSIX has it's own ideas of what a paragraph boundary is and it
-       * doesn't match historical Vi: It also stops at a "{" in the
-       * first column and at an empty line. */
-      if (!first && did_skip && (startPS(curr, what, both)
-                                 || (posix && what == NUL && *ml_get(curr) ==
-                                     '{')))
+      if (!first && did_skip && startPS(curr, what, both))
         break;
 
       if (fold_skipped)