Fix vertical swapping regression with lua-spec files (and probs more)

Whoops, another case that wasn't tested. Easy fix though. I broke it
when I removed the coincident logic from nodes.get_current()

Author: aaronik

lua/treewalker/swap.lua

@@ -39,6 +39,7 @@ function M.swap_down()
   end
 
   local current = nodes.get_current()
+  current = nodes.get_highest_coincident(current)
   local current_augments = augment.get_node_augments(current)
   local current_all = { current, unpack(current_augments) }
   local current_all_rows = nodes.whole_range(current_all)
@@ -72,6 +73,7 @@ function M.swap_up()
   end
 
   local current = nodes.get_current()
+  current = nodes.get_highest_coincident(current)
   local current_augments = augment.get_node_augments(current)
   local current_all = { current, unpack(current_augments) }
   local current_all_rows = nodes.whole_range(current_all)

tests/fixtures/lua-spec.lua

@@ -64,7 +64,7 @@ describe("Treewalker", function()
   describe("lua spec file", function()
     load_buf(fixtures_dir .. "/lua.lua", "lua")
 
-    it("moves up and down at the same pace", function()
+    it("one", function()
       vim.fn.cursor(1, 1) -- Reset cursor
       treewalker.down()
       assert_cursor_at(3, 1)
@@ -84,7 +84,7 @@ describe("Treewalker", function()
       assert_cursor_at(1, 1)
     end)
 
-    it("goes into functions eagerly", function()
+    it("two", function()
       vim.fn.cursor(143, 1) -- In a bigger function
       treewalker.right()
       assert_cursor_at(144, 3)

tests/treewalker/swap_spec.lua

@@ -253,21 +253,42 @@ describe("Swapping in a lua test file:", function()
     assert.same('  { "<CMD>Treewalker SwapUp<CR>", "k", { desc = "up" } },', lines.get_line(102))
   end)
 
-  it("follows lateral swaps across rows (like in these it args)", function()
+  it("follows right swaps across rows (like in these it args)", function()
     vim.fn.cursor(21, 13)
     tw.swap_right()
     assert.same('    it(function()', lines.get_line(21))
     assert.same('    end, "moves up and down at the same pace")', lines.get_line(39))
     helpers.assert_cursor_at(39, 10)
   end)
 
-  it("follows lateral swaps across rows (like in these it args)", function()
+  it("follows left swaps across rows (like in these it args)", function()
     vim.fn.cursor(50, 13) -- go|es
     tw.swap_left()
     assert.same('    it("goes into functions eagerly", function()', lines.get_line(41))
     assert.same('    end)', lines.get_line(50))
     helpers.assert_cursor_at(41, 8)
   end)
+
+  it("swaps it blocks down", function()
+    assert.same('    it("one", function()', lines.get_line(67))
+    assert.same('    it("two", function()', lines.get_line(87))
+    vim.fn.cursor(67, 5) -- |it "one"
+    tw.swap_down()
+    assert.same('    it("two", function()', lines.get_line(67))
+    assert.same('    it("one", function()', lines.get_line(77))
+    helpers.assert_cursor_at(77, 5)
+  end)
+
+  it("swaps it blocks up", function()
+    assert.same('    it("one", function()', lines.get_line(67))
+    assert.same('    it("two", function()', lines.get_line(87))
+    vim.fn.cursor(87, 5) --|it "two"
+    tw.swap_up()
+    assert.same('    it("two", function()', lines.get_line(67))
+    assert.same('    it("one", function()', lines.get_line(77))
+    helpers.assert_cursor_at(67, 5)
+  end)
+
 end)
 
 -- doesn't work at all in md, doesn't need to