Add Next/Previous message to editor

doc/neogit.txt

@@ -56,6 +56,7 @@ CONTENTS                                                       *neogit_contents*
 
     7. Buffers                                                 |neogit_buffers|
        • Status                                          |neogit_status_buffer|
+       • Editor                                          |neogit_editor_buffer|
        • Log                                                |neogit_log_buffer|
        • Reflog                                          |neogit_reflog_buffer|
        • Commit                                          |neogit_commit_buffer|
@@ -1428,9 +1429,11 @@ Actions:                                         *neogit_worktree_popup_actions*
 7. Buffers                                                      *neogit_buffers*
 
 • Status                                                  |neogit_status_buffer|
+• Editor                                                  |neogit_editor_buffer|
 • Log                                                        |neogit_log_buffer|
 • Reflog                                                  |neogit_reflog_buffer|
 • Commit                                                  |neogit_commit_buffer|
+• Rebase Todo                                        |neogit_rebase_todo_buffer|
 
 ==============================================================================
 Status Buffer                                             *neogit_status_buffer*
@@ -1441,6 +1444,47 @@ Untracked Files                                 *neogit_status_buffer_untracked*
   untracked files entirely, "normal" to show files and directories (default),
   or "all" to show all files in all directories.
 
+==============================================================================
+Editor Buffer                                             *neogit_editor_buffer*
+
+Commands:                                               *neogit_editor_commands*
+  • Close                                                  *neogit_editor_close*
+    Default key: `q`
+
+    Closes the editor buffer. If there are unsaved changes, user will be
+    prompted to save them. Discarding the changes will abort.
+
+  • Submit                                                *neogit_editor_submit*
+    Default key: `<c-c><c-c>`
+
+    Writes and closes the editor.
+
+  • Abort                                                  *neogit_editor_abort*
+    Default key: `<c-c><c-k>`
+
+    Closes the editor buffer, discarding any changes that might have been
+    written.
+
+  • PrevMessage                                     *neogit_editor_prev_message*
+    Default key: `<m-p>`
+
+    Replaces the current commit message with the previously used one, via
+    reflog. Messages that have been discarded via reset will be included as
+    well. Any changes a user makes to a message will be stored while the
+    editor is open.
+
+  • NextMessage                                     *neogit_editor_next_message*
+    Default key: `<m-n>`
+
+    Replaces the current commit message with the next used one, via
+    reflog. Same semantics as |neogit_editor_prev_message| apply.
+
+  • ResetMessage                                   *neogit_editor_reset_message*
+    Default key: `<m-r>`
+
+    If a user has changed a message that was found via reflog, reset it to how
+    it appeared in reflog.
+
 ==============================================================================
 Log Buffer                                                   *neogit_log_buffer*
 (TODO)

lua/neogit/buffers/editor/init.lua

@@ -2,6 +2,7 @@ local Buffer = require("neogit.lib.buffer")
 local config = require("neogit.config")
 local input = require("neogit.lib.input")
 local util = require("neogit.lib.util")
+local git = require("neogit.lib.git")
 
 local pad = util.pad_right
 
@@ -42,6 +43,25 @@ function M:open(kind)
   local mapping = config.get_reversed_commit_editor_maps()
   local aborted = false
 
+  local message_index = 1
+  local message_buffer = { { "" } }
+  local footer
+
+  local function reflog_message(index)
+    return git.log.reflog_message(index - 2)
+  end
+
+  local function commit_message()
+    return message_buffer[message_index] or reflog_message(message_index)
+  end
+
+  local function current_message(buffer)
+    local message = buffer:get_lines(0, -1)
+    message = util.slice(message, 1, math.max(1, #message - #footer))
+
+    return message
+  end
+
   self.buffer = Buffer.create {
     name = self.filename,
     filetype = filetypes[self.filename:match("[%u_]+$")] or "NeogitEditor",
@@ -64,6 +84,9 @@ function M:open(kind)
         string.format("#   %s Close", pad_mapping("Close")),
         string.format("#   %s Submit", pad_mapping("Submit")),
         string.format("#   %s Abort", pad_mapping("Abort")),
+        string.format("#   %s Previous Message", pad_mapping("PrevMessage")),
+        string.format("#   %s Next Message", pad_mapping("NextMessage")),
+        string.format("#   %s Reset Message", pad_mapping("ResetMessage")),
       }
 
       help_lines = util.filter_map(help_lines, function(line)
@@ -77,6 +100,8 @@ function M:open(kind)
       buffer:write()
       buffer:move_cursor(1)
 
+      footer = buffer:get_lines(1, -1)
+
       -- Start insert mode if user has configured it
       local disable_insert = config.values.disable_insert_on_commit
       if
@@ -127,6 +152,31 @@ function M:open(kind)
           buffer:write()
           buffer:close(true)
         end,
+        [mapping["PrevMessage"]] = function(buffer)
+          local message = current_message(buffer)
+          message_buffer[message_index] = message
+
+          message_index = message_index + 1
+
+          buffer:set_lines(0, #message, false, commit_message())
+          buffer:move_cursor(1)
+        end,
+        [mapping["NextMessage"]] = function(buffer)
+          local message = current_message(buffer)
+
+          if message_index > 1 then
+            message_buffer[message_index] = message
+            message_index = message_index - 1
+          end
+
+          buffer:set_lines(0, #message, false, commit_message())
+          buffer:move_cursor(1)
+        end,
+        [mapping["ResetMessage"]] = function(buffer)
+          local message = current_message(buffer)
+          buffer:set_lines(0, #message, false, reflog_message(message_index))
+          buffer:move_cursor(1)
+        end,
       },
     },
   }

lua/neogit/config.lua

@@ -114,7 +114,7 @@ end
 
 ---@alias NeogitConfigMappingsRebaseEditor "Pick" | "Reword" | "Edit" | "Squash" | "Fixup" | "Execute" | "Drop" | "Break" | "MoveUp" | "MoveDown" | "Close" | "OpenCommit" | "Submit" | "Abort" | false | fun()
 ---
----@alias NeogitConfigMappingsCommitEditor "Close" | "Submit" | "Abort" | false | fun()
+---@alias NeogitConfigMappingsCommitEditor "Close" | "Submit" | "Abort" | "PrevMessage" | "ResetMessage" | "NextMessage" | false | fun()
 
 ---@class NeogitConfigMappings Consult the config file or documentation for values
 ---@field finder? { [string]: NeogitConfigMappingsFinder } A dictionary that uses finder commands to set multiple keybinds
@@ -301,6 +301,9 @@ function M.get_default_values()
         ["q"] = "Close",
         ["<c-c><c-c>"] = "Submit",
         ["<c-c><c-k>"] = "Abort",
+        ["<m-p>"] = "PrevMessage",
+        ["<m-n>"] = "NextMessage",
+        ["<m-r>"] = "ResetMessage",
       },
       rebase_editor = {
         ["p"] = "Pick",

lua/neogit/lib/buffer.lua

@@ -81,7 +81,7 @@ function Buffer:write()
 end
 
 function Buffer:get_lines(first, last, strict)
-  return api.nvim_buf_get_lines(self.handle, first, last, strict)
+  return api.nvim_buf_get_lines(self.handle, first, last, strict or false)
 end
 
 function Buffer:get_line(line)
@@ -148,13 +148,7 @@ function Buffer:set_text(first_line, last_line, first_col, last_col, lines)
 end
 
 function Buffer:move_cursor(line)
-  if line < 0 then
-    self:focus()
-    vim.cmd("norm! G")
-  else
-    self:focus()
-    vim.cmd("norm! " .. line .. "G")
-  end
+  api.nvim_win_set_cursor(0, { line, 0 })
 end
 
 function Buffer:close(force)

lua/neogit/lib/git/log.lua

@@ -535,4 +535,12 @@ M.branch_info = util.memoize(function(ref, remotes)
   return result
 end)
 
+function M.reflog_message(skip)
+  return cli.log
+    .format("%B")
+    .max_count(1)
+    .args("--reflog", "--no-merges", "--skip=" .. tostring(skip))
+    .call_sync({ ignore_error = true }).stdout
+end
+
 return M

lua/neogit/lib/util.lua

@@ -193,20 +193,20 @@ function M.str_min_width(str, len, sep)
   return str .. string.rep(sep or " ", len - length)
 end
 
--- function M.slice(tbl, s, e)
---   local pos, new = 1, {}
---
---   if e == nil then
---     e = #tbl
---   end
---
---   for i = s, e do
---     new[pos] = tbl[i]
---     pos = pos + 1
---   end
---
---   return new
--- end
+function M.slice(tbl, s, e)
+  local pos, new = 1, {}
+
+  if e == nil then
+    e = #tbl
+  end
+
+  for i = s, e do
+    new[pos] = tbl[i]
+    pos = pos + 1
+  end
+
+  return new
+end
 
 -- function M.str_count(str, target)
 --   local count = 0