vim-patch:8.2.3280: 'virtualedit' local to buffer is not the best solution

Problem:    'virtualedit' local to buffer is not the best solution.
Solution:   Make it window-local. (Gary Johnson, closes vim/vim#8685)
https://github.com/vim/vim/commit/51ad850f5fbafa7aa3f60affa74ec9c9f992c6cc

8 files changed, 54 insertions, 36 deletions

diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index 08f719f16c..4536079cea 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -6782,7 +6782,7 @@ A jump table for the options with a short description can be found at |Q_op|.
 
 					    *'virtualedit'* *'ve'*
 'virtualedit' 've'	string	(default "")
-			global or local to buffer |global-local|
+			global or local to window |global-local|
 	A comma separated list of these words:
 	    block	Allow virtual editing in Visual block mode.
 	    insert	Allow virtual editing in Insert mode.
diff --git a/src/nvim/buffer.c b/src/nvim/buffer.c
index 3753d67d54..abd22fba26 100644
--- a/src/nvim/buffer.c
+++ b/src/nvim/buffer.c
@@ -1941,7 +1941,6 @@ void free_buf_options(buf_T *buf, int free_p_ff)
   clear_string_option(&buf->b_p_lw);
   clear_string_option(&buf->b_p_bkc);
   clear_string_option(&buf->b_p_menc);
-  clear_string_option(&buf->b_p_ve);
 }
 
 
diff --git a/src/nvim/buffer_defs.h b/src/nvim/buffer_defs.h
index a14dfff085..2856a7390d 100644
--- a/src/nvim/buffer_defs.h
+++ b/src/nvim/buffer_defs.h
@@ -204,6 +204,10 @@ typedef struct {
 #define w_p_nu w_onebuf_opt.wo_nu       // 'number'
   int wo_rnu;
 #define w_p_rnu w_onebuf_opt.wo_rnu     // 'relativenumber'
+  char_u *wo_ve;
+#define w_p_ve w_onebuf_opt.wo_ve       // 'virtualedit'
+  unsigned wo_ve_flags;
+#define w_ve_flags w_onebuf_opt.wo_ve_flags  // flags for 'virtualedit'
   long wo_nuw;
 #define w_p_nuw w_onebuf_opt.wo_nuw    // 'numberwidth'
   int wo_wfh;
@@ -772,8 +776,6 @@ struct file_buffer {
   long b_p_ul;                  ///< 'undolevels' local value
   int b_p_udf;                  ///< 'undofile'
   char_u *b_p_lw;               ///< 'lispwords' local value
-  char_u *b_p_ve;               ///< 'virtualedit' local value
-  unsigned b_ve_flags;          ///< flags for 'virtualedit'
 
   // end of buffer options
 
diff --git a/src/nvim/ops.c b/src/nvim/ops.c
index 74033df313..c845bd3717 100644
--- a/src/nvim/ops.c
+++ b/src/nvim/ops.c
@@ -2197,21 +2197,21 @@ void op_insert(oparg_T *oap, long count1)
     // already disabled, but still need it when calling
     // coladvance_force().
     // coladvance_force() uses get_ve_flags() to get the 'virtualedit'
-    // state for the current buffer.  To override that state, we need to
-    // set the buffer-local value of ve_flags rather than the global value.
+    // state for the current window.  To override that state, we need to
+    // set the window-local value of ve_flags rather than the global value.
     if (curwin->w_cursor.coladd > 0) {
-      unsigned old_ve_flags = curbuf->b_ve_flags;
+      unsigned old_ve_flags = curwin->w_ve_flags;
 
       if (u_save_cursor() == FAIL) {
         return;
       }
-      curbuf->b_ve_flags = VE_ALL;
+      curwin->w_ve_flags = VE_ALL;
       coladvance_force(oap->op_type == OP_APPEND
           ? oap->end_vcol + 1 : getviscol());
       if (oap->op_type == OP_APPEND) {
         --curwin->w_cursor.col;
       }
-      curbuf->b_ve_flags = old_ve_flags;
+      curwin->w_ve_flags = old_ve_flags;
     }
     // Get the info about the block before entering the text
     block_prep(oap, &bd, oap->start.lnum, true);
diff --git a/src/nvim/option.c b/src/nvim/option.c
index fd4cc9ebb2..a79523f800 100644
--- a/src/nvim/option.c
+++ b/src/nvim/option.c
@@ -2065,7 +2065,6 @@ void check_buf_options(buf_T *buf)
   check_string_option(&buf->b_p_menc);
   check_string_option(&buf->b_p_vsts);
   check_string_option(&buf->b_p_vts);
-  check_string_option(&buf->b_p_ve);
 }
 
 /// Free the string allocated for an option.
@@ -3090,8 +3089,8 @@ ambw_end:
     unsigned int *flags = &ve_flags;
 
     if (opt_flags & OPT_LOCAL) {
-      ve = curbuf->b_p_ve;
-      flags = &curbuf->b_ve_flags;
+      ve = curwin->w_p_ve;
+      flags = &curwin->w_ve_flags;
     }
 
     if ((opt_flags & OPT_LOCAL) && *ve == NUL) {
@@ -5763,8 +5762,8 @@ void unset_global_local_option(char *name, void *from)
     redraw_later((win_T *)from, NOT_VALID);
     break;
   case PV_VE:
-    clear_string_option(&buf->b_p_ve);
-    buf->b_ve_flags = 0;
+    clear_string_option(&((win_T *)from)->w_p_ve);
+    ((win_T *)from)->w_ve_flags = 0;
     break;
   }
 }
@@ -5833,7 +5832,7 @@ static char_u *get_varp_scope(vimoption_T *p, int opt_flags)
     case PV_LCS:
       return (char_u *)&(curwin->w_p_lcs);
     case PV_VE:
-      return (char_u *)&(curbuf->b_p_ve);
+      return (char_u *)&(curwin->w_p_ve);
     }
     return NULL;     // "cannot happen"
   }
@@ -5928,6 +5927,9 @@ static char_u *get_varp(vimoption_T *p)
   case PV_LCS:
     return *curwin->w_p_lcs != NUL
            ? (char_u *)&(curwin->w_p_lcs) : p->var;
+  case PV_VE:
+    return *curwin->w_p_ve != NUL
+           ? (char_u *)&curwin->w_p_ve : p->var;
 
   case PV_ARAB:
     return (char_u *)&(curwin->w_p_arab);
@@ -6126,8 +6128,6 @@ static char_u *get_varp(vimoption_T *p)
     return (char_u *)&(curbuf->b_p_vsts);
   case PV_VTS:
     return (char_u *)&(curbuf->b_p_vts);
-  case PV_VE:
-    return *curbuf->b_p_ve != NUL ? (char_u *)&curbuf->b_p_ve : p->var;
   case PV_KMAP:
     return (char_u *)&(curbuf->b_p_keymap);
   case PV_SCL:
@@ -6170,6 +6170,8 @@ void copy_winopt(winopt_T *from, winopt_T *to)
   to->wo_list = from->wo_list;
   to->wo_nu = from->wo_nu;
   to->wo_rnu = from->wo_rnu;
+  to->wo_ve = vim_strsave(from->wo_ve);
+  to->wo_ve_flags = from->wo_ve_flags;
   to->wo_nuw = from->wo_nuw;
   to->wo_rl  = from->wo_rl;
   to->wo_rlc = vim_strsave(from->wo_rlc);
@@ -6246,6 +6248,7 @@ static void check_winopt(winopt_T *wop)
   check_string_option(&wop->wo_winhl);
   check_string_option(&wop->wo_fcs);
   check_string_option(&wop->wo_lcs);
+  check_string_option(&wop->wo_ve);
 }
 
 /// Free the allocated memory inside a winopt_T.
@@ -6270,6 +6273,7 @@ void clear_winopt(winopt_T *wop)
   clear_string_option(&wop->wo_winhl);
   clear_string_option(&wop->wo_fcs);
   clear_string_option(&wop->wo_lcs);
+  clear_string_option(&wop->wo_ve);
 }
 
 void didset_window_options(win_T *wp)
@@ -6460,8 +6464,6 @@ void buf_copy_options(buf_T *buf, int flags)
       buf->b_p_udf = p_udf;
       buf->b_p_lw = empty_option;
       buf->b_p_menc = empty_option;
-      buf->b_p_ve = empty_option;
-      buf->b_ve_flags = 0;
 
       /*
        * Don't copy the options set by ex_help(), use the saved values,
@@ -7842,7 +7844,7 @@ unsigned int get_bkc_value(buf_T *buf)
 /// Get the local or global value of the 'virtualedit' flags.
 unsigned int get_ve_flags(void)
 {
-  return (curbuf->b_ve_flags ? curbuf->b_ve_flags : ve_flags) & ~(VE_NONE | VE_NONEU);
+  return (curwin->w_ve_flags ? curwin->w_ve_flags : ve_flags) & ~(VE_NONE | VE_NONEU);
 }
 
 /// Get the local or global value of 'showbreak'.
diff --git a/src/nvim/option_defs.h b/src/nvim/option_defs.h
index aed2868a09..db8bc83395 100644
--- a/src/nvim/option_defs.h
+++ b/src/nvim/option_defs.h
@@ -711,8 +711,8 @@ static char *(p_ve_values[]) = { "block", "insert", "all", "onemore", "none", "N
 #define VE_INSERT      6U      // includes "all"
 #define VE_ALL         4U
 #define VE_ONEMORE     8U
-#define VE_NONE        16U
-#define VE_NONEU       32U     // Upper-case NONE
+#define VE_NONE        16U     // "none"
+#define VE_NONEU       32U     // "NONE"
 EXTERN long p_verbose;          // 'verbose'
 #ifdef IN_OPTION_C
 char_u *p_vfile = (char_u *)"";   // used before options are initialized
diff --git a/src/nvim/screen.c b/src/nvim/screen.c
index 9aea42cda3..9b253fad01 100644
--- a/src/nvim/screen.c
+++ b/src/nvim/screen.c
@@ -1215,14 +1215,14 @@ static void win_update(win_T *wp, Providers *providers)
        */
       if (VIsual_mode == Ctrl_V) {
         colnr_T fromc, toc;
-        unsigned int save_ve_flags = curbuf->b_ve_flags;
+        unsigned int save_ve_flags = curwin->w_ve_flags;
 
         if (curwin->w_p_lbr) {
-          curbuf->b_ve_flags = VE_ALL;
+          curwin->w_ve_flags = VE_ALL;
         }
 
         getvcols(wp, &VIsual, &curwin->w_cursor, &fromc, &toc);
-        curbuf->b_ve_flags = save_ve_flags;
+        curwin->w_ve_flags = save_ve_flags;
         toc++;
         // Highlight to the end of the line, unless 'virtualedit' has
         // "block".
diff --git a/src/nvim/testdir/test_virtualedit.vim b/src/nvim/testdir/test_virtualedit.vim
index c19a9500bd..d2a5258bd3 100644
--- a/src/nvim/testdir/test_virtualedit.vim
+++ b/src/nvim/testdir/test_virtualedit.vim
@@ -263,7 +263,7 @@ endfunc
 let s:result_ve_on  = 'a      x'
 let s:result_ve_off = 'x'
 
-" Utility function for Test_global_local()
+" Utility function for Test_global_local_virtualedit()
 func s:TryVirtualeditReplace()
   call setline(1, 'a')
   normal gg7l
@@ -271,7 +271,7 @@ func s:TryVirtualeditReplace()
 endfunc
 
 " Test for :set and :setlocal
-func Test_global_local()
+func Test_global_local_virtualedit()
   new
 
   " Verify that 'virtualedit' is initialized to empty, can be set globally to
@@ -291,8 +291,8 @@ func Test_global_local()
   call s:TryVirtualeditReplace()
   call assert_equal(s:result_ve_off, getline(1))
 
-  " Verify that :set affects multiple buffers
-  new
+  " Verify that :set affects multiple windows.
+  split
   set ve=all
   call s:TryVirtualeditReplace()
   call assert_equal(s:result_ve_on, getline(1))
@@ -305,17 +305,15 @@ func Test_global_local()
   call assert_equal(s:result_ve_off, getline(1))
   bwipe!
 
-  " Verify that :setlocal affects only the current buffer
-  setlocal ve=all
+  " Verify that :setlocal affects only the current window.
   new
-  call s:TryVirtualeditReplace()
-  call assert_equal(s:result_ve_off, getline(1))
+  split
   setlocal ve=all
-  wincmd p
-  setlocal ve=
-  wincmd p
   call s:TryVirtualeditReplace()
   call assert_equal(s:result_ve_on, getline(1))
+  wincmd p
+  call s:TryVirtualeditReplace()
+  call assert_equal(s:result_ve_off, getline(1))
   bwipe!
   call s:TryVirtualeditReplace()
   call assert_equal(s:result_ve_off, getline(1))
@@ -374,6 +372,23 @@ func Test_global_local()
 
   bwipe!
 
+  " Verify that the 'virtualedit' state is copied to new windows.
+  new
+  call s:TryVirtualeditReplace()
+  call assert_equal(s:result_ve_off, getline(1))
+  split
+  setlocal ve=all
+  call s:TryVirtualeditReplace()
+  call assert_equal(s:result_ve_on, getline(1))
+  split
+  call s:TryVirtualeditReplace()
+  call assert_equal(s:result_ve_on, getline(1))
+  setlocal ve=
+  split
+  call s:TryVirtualeditReplace()
+  call assert_equal(s:result_ve_off, getline(1))
+  bwipe!
+
   setlocal virtualedit&
   set virtualedit&
 endfunc