feat(git): replace vim-fugitive with custom git module

lua/git/status_win.lua

@@ -1,3 +1,4 @@
+local diff = require("git.diff")
 local log = require("log")
 local repo = require("git.repo")
 
@@ -361,109 +362,6 @@ local function current_entry(bufnr)
     return s, s.lines[lnum]
 end
 
----@param buf integer
----@param worktree string
----@param path string
-local function attach_index_writer(buf, worktree, path)
-    vim.api.nvim_create_autocmd("BufWriteCmd", {
-        buffer = buf,
-        callback = function()
-            local body = table.concat(
-                vim.api.nvim_buf_get_lines(buf, 0, -1, false),
-                "\n"
-            ) .. "\n"
-            local hash = vim.system(
-                { "git", "hash-object", "-w", "--stdin" },
-                { cwd = worktree, stdin = body, text = true }
-            ):wait()
-            if hash.code ~= 0 then
-                log.error("git hash-object failed: %s", hash.stderr or "")
-                return
-            end
-            local sha = vim.trim(hash.stdout or "")
-            local mode = "100644"
-            local ls = vim.system(
-                { "git", "ls-files", "-s", "--", path },
-                { cwd = worktree, text = true }
-            ):wait()
-            if ls.code == 0 and ls.stdout then
-                local m = ls.stdout:match("^(%d+)")
-                if m then
-                    mode = m
-                end
-            end
-            local upd = vim.system({
-                "git",
-                "update-index",
-                "--cacheinfo",
-                mode .. "," .. sha .. "," .. path,
-            }, { cwd = worktree, text = true }):wait()
-            if upd.code ~= 0 then
-                log.error("git update-index failed: %s", upd.stderr or "")
-                return
-            end
-            vim.bo[buf].modified = false
-        end,
-    })
-end
-
----@param worktree string
----@param ref string '' for index, 'HEAD' for HEAD
----@param path string
----@param is_index boolean? true to hook :w to update the git index
----@return integer
-local function git_show_buf(worktree, ref, path, is_index)
-    local result = vim.system(
-        { "git", "show", ref .. ":" .. path },
-        { cwd = worktree, text = true }
-    ):wait()
-    local content = result.code == 0 and (result.stdout or "") or ""
-    local lines = vim.split(content, "\n", { plain = true, trimempty = false })
-    if #lines > 0 and lines[#lines] == "" then
-        table.remove(lines)
-    end
-    local buf = vim.api.nvim_create_buf(false, true)
-    vim.api.nvim_buf_set_lines(buf, 0, -1, false, lines)
-    vim.bo[buf].buftype = is_index and "acwrite" or "nofile"
-    vim.bo[buf].bufhidden = "wipe"
-    vim.bo[buf].swapfile = false
-    if not is_index then
-        vim.bo[buf].modifiable = false
-    end
-    if is_index then
-        attach_index_writer(buf, worktree, path)
-    end
-    vim.bo[buf].modified = false
-    return buf
-end
-
----@return integer
-local function empty_buf()
-    local buf = vim.api.nvim_create_buf(false, true)
-    vim.bo[buf].buftype = "nofile"
-    vim.bo[buf].bufhidden = "wipe"
-    vim.bo[buf].swapfile = false
-    vim.bo[buf].modifiable = false
-    vim.bo[buf].modified = false
-    return buf
-end
-
----@param abs_path string
----@return integer
-local function load_file_buf(abs_path)
-    for _, buf in ipairs(vim.api.nvim_list_bufs()) do
-        if
-            vim.api.nvim_buf_is_loaded(buf)
-            and vim.api.nvim_buf_get_name(buf) == abs_path
-        then
-            return buf
-        end
-    end
-    local buf = vim.fn.bufadd(abs_path)
-    vim.fn.bufload(buf)
-    return buf
-end
-
 ---@class ow.Git.DiffSide
 ---@field buf integer
 ---@field name string?
@@ -478,7 +376,8 @@ end
 ---@return ow.Git.DiffSide
 local function head_pane(worktree, path, content)
     return {
-        buf = content and git_show_buf(worktree, "HEAD", path) or empty_buf(),
+        buf = content and diff.git_show_buf(worktree, "HEAD", path)
+            or diff.empty_buf(),
         name = "git://HEAD/" .. path,
     }
 end
@@ -490,11 +389,11 @@ end
 local function worktree_pane(worktree, path, exists)
     if exists then
         return {
-            buf = load_file_buf(vim.fs.joinpath(worktree, path)),
+            buf = diff.load_file_buf(vim.fs.joinpath(worktree, path)),
             name = nil,
         }
     end
-    return { buf = empty_buf(), name = "git://worktree/" .. path }
+    return { buf = diff.empty_buf(), name = "git://worktree/" .. path }
 end
 
 ---@param s ow.Git.StatusState
@@ -506,8 +405,8 @@ local function index_pane(s, entry)
         or (entry.section == "Staged" and entry.x == "D")
     )
     return {
-        buf = in_index and git_show_buf(s.worktree, "", entry.path, true)
-            or empty_buf(),
+        buf = in_index and diff.git_show_buf(s.worktree, "", entry.path, true)
+            or diff.empty_buf(),
         name = "git://index/" .. entry.path,
     }
 end