fix: Reverse hash order for consistent diff logic and update test cases

Author: silviu

lua/gitlogdiff/actions.lua

@@ -11,17 +11,17 @@ function M.show_selected(hashes)
     return
   end
 
-  local ordered = vim.deepcopy(hashes)
-  table.sort(ordered, function(a, b)
-    return a < b
-  end)
+  local ordered = {}
+  for i = #hashes, 1, -1 do
+    table.insert(ordered, hashes[i])
+  end
 
   if #ordered == 1 then
     diffview_open({ ordered[1] .. "^.." .. ordered[1] })
     return
   end
 
-  diffview_open(ordered)
+  diffview_open({ ordered[1] .. ".." .. ordered[#ordered] })
 end
 
 return M

lua/gitlogdiff/ui.lua

@@ -69,10 +69,12 @@ end
 
 function M.get_selected_hashes()
   local hashes = {}
-  for i, ok in pairs(M.state.selected) do
-    if ok then
+  for i = 1, #M.state.commits do
+    if M.state.selected[i] then
       local h = M.state.commits[i]:match("^(%w+)")
-      table.insert(hashes, h)
+      if h then
+        table.insert(hashes, h)
+      end
     end
   end
   return hashes

tests/test_init.lua

@@ -34,8 +34,8 @@ T["actions"]["show_selected() diffs two commits correctly"] = function()
     table.insert(cmds, cmd)
   end
 
-  actions.show_selected({ "def5678", "abc1234" })
-  MiniTest.expect.equality(cmds[1], "DiffviewOpen abc1234 def5678")
+  actions.show_selected({ "newer123", "older456" })
+  MiniTest.expect.equality(cmds[1], "DiffviewOpen older456..newer123")
 end
 
 T["log"] = MiniTest.new_set()

tests/test_ui.lua

@@ -43,7 +43,6 @@ T["get_selected_hashes() works"] = function()
   ui.state.selected[3] = true
 
   local hashes = ui.get_selected_hashes()
-  table.sort(hashes)
   MiniTest.expect.equality(hashes, { "abc1234", "ghi9012" })
 end