vim-patch:8.0.0388

Fix a problem when filtering manually folded lines

When foldMarkAdjustRecurse() is called to adjust folds that start inside
the range of lines that are being moved and end outside that range, it
calculates `amount_after` for its recursive call incorrectly.
The calculation assumes that folds inside the changed range are being
deleted, but this is not always the case.

This means nested folds that start after the changed range of lines are
shifted an incorrect amount.

We fix this by calculating the `amount_after` differently if the folds
inside the changed range are not being deleted.

3 files changed, 55 insertions, 5 deletions

diff --git a/src/nvim/ex_docmd.c b/src/nvim/ex_docmd.c
index ff0df9e51c..87b6959101 100644
--- a/src/nvim/ex_docmd.c
+++ b/src/nvim/ex_docmd.c
@@ -3654,10 +3654,10 @@ static linenr_T get_address(exarg_T *eap,
         n = 1;
       else
         n = getdigits(&cmd);
-      if (addr_type == ADDR_LOADED_BUFFERS || addr_type == ADDR_BUFFERS)
+      if (addr_type == ADDR_LOADED_BUFFERS || addr_type == ADDR_BUFFERS) {
         lnum = compute_buffer_local_count(
             addr_type, lnum, (i == '-') ? -1 * n : n);
-      else {
+      } else {
         // Relative line addressing, need to adjust for folded lines
         // now, but only do it after the first address.
         if (addr_type == ADDR_LINES && (i == '-' || i == '+')
diff --git a/src/nvim/fold.c b/src/nvim/fold.c
index d964da371a..1423463800 100644
--- a/src/nvim/fold.c
+++ b/src/nvim/fold.c
@@ -1438,13 +1438,16 @@ static void foldMarkAdjustRecurse(garray_T *gap, linenr_T line1, linenr_T line2,
         } else {
           /* 5. fold is below line1 and contains line2; need to
            * correct nested folds too */
-          foldMarkAdjustRecurse(&fp->fd_nested, line1 - fp->fd_top,
-              line2 - fp->fd_top, amount,
-              amount_after + (fp->fd_top - top));
           if (amount == MAXLNUM) {
+            foldMarkAdjustRecurse(&fp->fd_nested, line1 - fp->fd_top,
+                                  line2 - fp->fd_top, amount,
+                                  amount_after + (fp->fd_top - top));
             fp->fd_len -= line2 - fp->fd_top + 1;
             fp->fd_top = line1;
           } else {
+            foldMarkAdjustRecurse(&fp->fd_nested, line1 - fp->fd_top,
+                                  line2 - fp->fd_top, amount,
+                                  amount_after - amount);
             fp->fd_len += amount_after - amount;
             fp->fd_top += amount;
           }
diff --git a/test/functional/normal/fold_spec.lua b/test/functional/normal/fold_spec.lua
new file mode 100644
index 0000000000..a2a2a35a8b
--- /dev/null
+++ b/test/functional/normal/fold_spec.lua
@@ -0,0 +1,47 @@
+local helpers = require('test.functional.helpers')(after_each)
+
+local clear = helpers.clear
+local insert = helpers.insert
+local feed = helpers.feed
+local expect = helpers.expect
+local execute = helpers.execute
+
+describe('Folds', function()
+  clear()
+  it('manual folding adjusts with filter', function()
+    insert([[
+    1
+    2
+    3
+    4
+    5
+    6
+    7
+    8
+    9
+    10
+    11
+    12
+    13
+    14
+    15
+    16
+    17
+    18
+    19
+    20]])
+    execute('4,$fold', '%foldopen', '10,$fold', '%foldopen')
+    execute('1,8! cat')
+    feed('5ggzdzMGdd')
+    expect([[
+    1
+    2
+    3
+    4
+    5
+    6
+    7
+    8
+    9]])
+  end)
+end)