vim-patch:8.0.1024

Problem:    Manual folds are lost when a session file has the same buffer in
            two windows. (Jeansen)
Solution:   Use ":edit" only once. (Christian Brabandt, closes vim/vim#1958)

https://github.com/vim/vim/commit/4bebc9a0565670b853d227f81a9a31eafdb47eed

3 files changed, 209 insertions, 17 deletions

diff --git a/src/nvim/ex_docmd.c b/src/nvim/ex_docmd.c
index 5145c65bc7..87d9e10619 100644
--- a/src/nvim/ex_docmd.c
+++ b/src/nvim/ex_docmd.c
@@ -8813,7 +8813,7 @@ makeopens (
                   buf->b_wininfo == NULL ?
                     (int64_t)1L :
                     (int64_t)buf->b_wininfo->wi_fpos.lnum) < 0
-          || ses_fname(fd, buf, &ssop_flags) == FAIL)
+          || ses_fname(fd, buf, &ssop_flags, true) == FAIL)
         return FAIL;
     }
   }
@@ -8885,7 +8885,7 @@ makeopens (
           && !bt_nofile(wp->w_buffer)
           ) {
         if (fputs(need_tabnew ? "tabedit " : "edit ", fd) < 0
-            || ses_fname(fd, wp->w_buffer, &ssop_flags) == FAIL)
+            || ses_fname(fd, wp->w_buffer, &ssop_flags, true) == FAIL)
           return FAIL;
         need_tabnew = FALSE;
         if (!wp->w_arg_idx_invalid)
@@ -9223,21 +9223,30 @@ put_view (
     if (wp->w_buffer->b_ffname != NULL
         && (!bt_nofile(wp->w_buffer) || wp->w_buffer->terminal)
         ) {
-      /*
-       * Editing a file in this buffer: use ":edit file".
-       * This may have side effects! (e.g., compressed or network file).
-       */
-      if (fputs("edit ", fd) < 0
-          || ses_fname(fd, wp->w_buffer, flagp) == FAIL)
+      // Editing a file in this buffer: use ":edit file".
+      // This may have side effects! (e.g., compressed or network file).
+      //
+      // Note, if a buffer for that file already exists, use :badd to
+      // edit that buffer, to not lose folding information (:edit resets
+      // folds in other buffers)
+      if (fputs("if bufexists('", fd) < 0
+          || ses_fname(fd, wp->w_buffer, flagp, false) == FAIL
+          || fputs("') | buffer ", fd) < 0
+          || ses_fname(fd, wp->w_buffer, flagp, false) == FAIL
+          || fputs(" | else | edit ", fd) < 0
+          || ses_fname(fd, wp->w_buffer, flagp, false) == FAIL
+          || fputs(" | endif", fd) < 0
+          || put_eol(fd) == FAIL) {
         return FAIL;
+      }
     } else {
       /* No file in this buffer, just make it empty. */
       if (put_line(fd, "enew") == FAIL)
         return FAIL;
       if (wp->w_buffer->b_ffname != NULL) {
-        /* The buffer does have a name, but it's not a file name. */
+        // The buffer does have a name, but it's not a file name.
         if (fputs("file ", fd) < 0
-            || ses_fname(fd, wp->w_buffer, flagp) == FAIL)
+            || ses_fname(fd, wp->w_buffer, flagp, true) == FAIL)
           return FAIL;
       }
       do_cursor = FALSE;
@@ -9391,12 +9400,10 @@ ses_arglist (
   return OK;
 }
 
-/*
- * Write a buffer name to the session file.
- * Also ends the line.
- * Returns FAIL if writing fails.
- */
-static int ses_fname(FILE *fd, buf_T *buf, unsigned *flagp)
+/// Write a buffer name to the session file.
+/// Also ends the line, if "add_eol" is true.
+/// Returns FAIL if writing fails.
+static int ses_fname(FILE *fd, buf_T *buf, unsigned *flagp, bool add_eol)
 {
   char_u      *name;
 
@@ -9413,8 +9420,10 @@ static int ses_fname(FILE *fd, buf_T *buf, unsigned *flagp)
     name = buf->b_sfname;
   else
     name = buf->b_ffname;
-  if (ses_put_fname(fd, name, flagp) == FAIL || put_eol(fd) == FAIL)
+  if (ses_put_fname(fd, name, flagp) == FAIL
+      || (add_eol && put_eol(fd) == FAIL)) {
     return FAIL;
+  }
   return OK;
 }
 
diff --git a/src/nvim/testdir/test_mksession.vim b/src/nvim/testdir/test_mksession.vim
index 7158b31a14..13fb07c7e0 100644
--- a/src/nvim/testdir/test_mksession.vim
+++ b/src/nvim/testdir/test_mksession.vim
@@ -121,4 +121,36 @@ func Test_mksession_arglist()
   argdel *
 endfunc
 
+
+func Test_mksession_one_buffer_two_windows()
+  edit Xtest1
+  new Xtest2
+  split
+  mksession! Xtest_mks.out
+  let lines = readfile('Xtest_mks.out')
+  let count1 = 0
+  let count2 = 0
+  let count2buf = 0
+  for line in lines
+    if line =~ 'edit \f*Xtest1$'
+      let count1 += 1
+    endif
+    if line =~ 'edit \f\{-}Xtest2'
+      let count2 += 1
+    endif
+    if line =~ 'buffer \f\{-}Xtest2'
+      let count2buf += 1
+    endif
+  endfor
+  call assert_equal(1, count1, 'Xtest1 count')
+  call assert_equal(2, count2, 'Xtest2 count')
+  call assert_equal(2, count2buf, 'Xtest2 buffer count')
+
+  close
+  bwipe!
+  !cp Xtest_mks.out /tmp
+  call delete('Xtest_mks.out')
+endfunc
+
+
 " vim: shiftwidth=2 sts=2 expandtab
diff --git a/src/nvim/version.c b/src/nvim/version.c
index 580ed592ca..9f75f75d4f 100644
--- a/src/nvim/version.c
+++ b/src/nvim/version.c
@@ -77,6 +77,157 @@ static char *features[] = {
 
 // clang-format off
 static const int included_patches[] = {
+  // 1026,
+  // 1025,
+  1024,
+  // 1023,
+  // 1022,
+  // 1021,
+  // 1020,
+  // 1019,
+  // 1018,
+  // 1017,
+  // 1016,
+  // 1015,
+  // 1014,
+  // 1013,
+  // 1012,
+  // 1011,
+  // 1010,
+  // 1009,
+  // 1008,
+  // 1007,
+  // 1006,
+  // 1005,
+  // 1004,
+  // 1003,
+  // 1002,
+  // 1001,
+  // 1000,
+  // 999,
+  // 998,
+  // 997,
+  // 996,
+  // 995,
+  // 994,
+  // 993,
+  // 992,
+  // 991,
+  // 990,
+  // 989,
+  // 988,
+  // 987,
+  // 986,
+  // 985,
+  // 984,
+  // 983,
+  // 982,
+  // 981,
+  // 980,
+  // 979,
+  // 978,
+  // 977,
+  // 976,
+  // 975,
+  // 974,
+  // 973,
+  // 972,
+  // 971,
+  // 970,
+  // 969,
+  // 968,
+  // 967,
+  // 966,
+  // 965,
+  // 964,
+  // 963,
+  // 962,
+  // 961,
+  // 960,
+  // 959,
+  // 958,
+  // 957,
+  // 956,
+  // 955,
+  // 954,
+  // 953,
+  // 952,
+  // 951,
+  // 950,
+  // 949,
+  // 948,
+  // 947,
+  // 946,
+  // 945,
+  // 944,
+  // 943,
+  // 942,
+  // 941,
+  // 940,
+  // 939,
+  // 938,
+  // 937,
+  // 936,
+  // 935,
+  // 934,
+  // 933,
+  // 932,
+  // 931,
+  // 930,
+  // 929,
+  // 928,
+  // 927,
+  // 926,
+  // 925,
+  // 924,
+  // 923,
+  // 922,
+  // 921,
+  // 920,
+  // 919,
+  // 918,
+  // 917,
+  // 916,
+  // 915,
+  // 914,
+  // 913,
+  // 912,
+  // 911,
+  // 910,
+  // 909,
+  // 908,
+  // 907,
+  // 906,
+  // 905,
+  // 904,
+  // 903,
+  // 902,
+  // 901,
+  // 900,
+  // 899,
+  // 898,
+  // 897,
+  // 896,
+  // 895,
+  // 894,
+  // 893,
+  // 892,
+  // 891,
+  // 890,
+  // 889,
+  // 888,
+  // 887,
+  // 886,
+  // 885,
+  // 884,
+  // 883,
+  // 882,
+  // 881,
+  // 880,
+  // 879,
+  // 878,
+  // 877,
+  // 876,
   // 875,
   // 874,
   // 873,