1 files changed, 186 insertions, 0 deletions
diff --git a/test/functional/normal/fold_spec.lua b/test/functional/normal/fold_spec.lua
index a2a2a35a8b..5584db20ba 100644
--- a/test/functional/normal/fold_spec.lua
+++ b/test/functional/normal/fold_spec.lua
@@ -5,9 +5,13 @@ local insert = helpers.insert
 local feed = helpers.feed
 local expect = helpers.expect
 local execute = helpers.execute
+local funcs = helpers.funcs
+local foldlevel, foldclosedend = funcs.foldlevel, funcs.foldclosedend
+local eq = helpers.eq
 
 describe('Folds', function()
   clear()
+  before_each(function() execute('enew!') end)
   it('manual folding adjusts with filter', function()
     insert([[
     1
@@ -44,4 +48,186 @@ describe('Folds', function()
     8
     9]])
   end)
+  describe('adjusting folds after :move', function()
+    local function manually_fold_indent()
+      -- setting foldmethod twice is a trick to get vim to set the folds for me
+      execute('set foldmethod=indent', 'set foldmethod=manual')
+      -- Ensure that all folds will get closed (makes it easier to test the
+      -- length of folds).
+      execute('set foldminlines=0')
+      -- Start with all folds open (so :move ranges aren't affected by closed
+      -- folds).
+      execute('%foldopen!')
+    end
+
+    local function get_folds()
+      local rettab = {}
+      for i = 1, funcs.line('$') do
+        table.insert(rettab, foldlevel(i))
+      end
+      return rettab
+    end
+
+    local function test_move_indent(insert_string, move_command)
+      -- This test is easy because we just need to ensure that the resulting
+      -- fold is the same as calculated when creating folds from scratch.
+      insert(insert_string)
+      execute(move_command)
+      local after_move_folds = get_folds()
+      -- Doesn't change anything, but does call foldUpdateAll()
+      execute('set foldminlines=0')
+      eq(after_move_folds, get_folds())
+      -- Set up the buffer with insert_string for the manual fold testing.
+      execute('enew!')
+      insert(insert_string)
+      manually_fold_indent()
+      execute(move_command)
+    end
+
+    it('neither closes nor corrupts folds', function()
+      test_move_indent([[
+a
+	a
+	a
+	a
+	a
+	a
+a
+	a
+	a
+		a
+	a
+	a
+a
+	a
+	a
+	a
+	a
+	a]], '7,12m0')
+      expect([[
+a
+	a
+	a
+		a
+	a
+	a
+a
+	a
+	a
+	a
+	a
+	a
+a
+	a
+	a
+	a
+	a
+	a]])
+      -- lines are not closed, folds are correct
+      for i = 1,funcs.line('$') do
+        eq(-1, funcs.foldclosed(i))
+        if i == 1 or i == 7 or i == 13 then
+          eq(0, foldlevel(i))
+        elseif i == 4 then
+          eq(2, foldlevel(i))
+        else
+          eq(1, foldlevel(i))
+        end
+      end
+      -- folds are not corrupted
+      feed('zM')
+      eq(6, foldclosedend(2))
+      eq(12, foldclosedend(8))
+      eq(18, foldclosedend(14))
+    end)
+    it("doesn't split a fold when the move is within it", function()
+      test_move_indent([[
+a
+	a
+	a
+		a
+		a
+		a
+		a
+	a
+	a
+a]], '5m6')
+      eq({0, 1, 1, 2, 2, 2, 2, 1, 1, 0}, get_folds())
+    end)
+    it('truncates folds that end in the moved range', function()
+      test_move_indent([[
+a
+	a
+		a
+		a
+		a
+a
+a]], '4,5m6')
+      eq({0, 1, 2, 0, 0, 0, 0}, get_folds())
+    end)
+    it('moves folds that start between moved range and destination', function()
+      test_move_indent([[
+a
+	a
+	a
+	a
+	a
+a
+a
+	a
+		a
+	a
+a
+a
+	a]], '3,4m$')
+      eq({0, 1, 1, 0, 0, 1, 2, 1, 0, 0, 1, 0, 0}, get_folds())
+    end)
+    it('does not affect folds outside changed lines', function()
+      test_move_indent([[
+	a
+	a
+	a
+a
+a
+a
+	a
+	a
+	a]], '4m5')
+      eq({1, 1, 1, 0, 0, 0, 1, 1, 1}, get_folds())
+    end)
+    it('moves and truncates folds that start in moved range', function()
+      test_move_indent([[
+a
+	a
+		a
+		a
+		a
+a
+a
+a
+a
+a]], '1,3m7')
+      eq({0, 0, 0, 0, 0, 1, 2, 0, 0, 0}, get_folds())
+    end)
+    it('breaks a fold when moving text into it', function()
+      test_move_indent([[
+a
+	a
+		a
+		a
+		a
+a
+a]], '$m4')
+      eq({0, 1, 2, 2, 0, 0, 0}, get_folds())
+    end)
+    it('adjusts correctly when moving a range backwards', function()
+      test_move_indent([[
+a
+	a
+		a
+		a
+a]], '2,3m0')
+      eq({1, 2, 0, 0, 0}, get_folds())
+    end)
+  end)
 end)