refactor(git): scratch buffers wipe by default, consolidate factories in util

lua/git/commit.lua

@@ -33,7 +33,6 @@ function M.commit(opts)
         proxy_buf = buf
         proxy_win = win
         vim.bo[buf].buftype = "acwrite"
-        vim.bo[buf].bufhidden = "wipe"
         vim.bo[buf].modifiable = true
         vim.api.nvim_buf_set_lines(buf, 0, -1, false, lines)
         vim.bo[buf].modified = false

lua/git/diff.lua

@@ -3,35 +3,6 @@ local util = require("git.util")
 
 local M = {}
 
----@class ow.Git.EmptyBufOpts
----@field name string?
----@field bufhidden ("hide"|"wipe")?  defaults to "wipe"
-
----Build a read-only scratch buffer, optionally naming it. When `opts.name`
----is set and a loaded buffer with that name already exists, returns it
----instead of creating a duplicate.
----@param opts ow.Git.EmptyBufOpts?
----@return integer
-function M.empty_buf(opts)
-    opts = opts or {}
-    if opts.name then
-        local existing = vim.fn.bufnr(opts.name)
-        if existing ~= -1 and vim.api.nvim_buf_is_loaded(existing) then
-            return existing
-        end
-    end
-    local buf = vim.api.nvim_create_buf(false, true)
-    vim.bo[buf].buftype = "nofile"
-    vim.bo[buf].bufhidden = opts.bufhidden or "wipe"
-    vim.bo[buf].swapfile = false
-    vim.bo[buf].modifiable = false
-    vim.bo[buf].modified = false
-    if opts.name then
-        pcall(vim.api.nvim_buf_set_name, buf, opts.name)
-    end
-    return buf
-end
-
 ---Name a buffer and re-run filetype detection from the (re-)set name.
 ---Wrapped in `pcall` because a buffer with that name may already exist
 ---(E95).

lua/git/log.lua

@@ -41,7 +41,9 @@ function M.show(opts)
         return
     end
 
-    local buf = util.new_scratch()
+    -- `hide` keeps the log around when the user navigates into a commit
+    -- via `<CR>` (which replaces the current buffer); `<C-^>` jumps back.
+    local buf = util.new_scratch({ bufhidden = "hide" })
     vim.b[buf].git_worktree = worktree
     vim.bo[buf].modifiable = true
     vim.api.nvim_buf_set_lines(buf, 0, -1, false, util.split_lines(stdout))

lua/git/object.lua

@@ -229,10 +229,7 @@ end
 local function blob_buf(worktree, blob, path, ref)
     local revspec = ref .. ":" .. path
     if is_zero(blob) then
-        return diff.empty_buf({
+        return util.empty_buf({ name = util.uri(revspec) })
-            name = util.uri(revspec),
-            bufhidden = "hide",
-        })
     end
     return M.buf_for(worktree, revspec)
 end
@@ -269,10 +266,7 @@ end
 ---@field split (false|"above"|"below"|"left"|"right")?  forwarded to `util.new_scratch`. Default opens a new horizontal split.
 
 ---Place a `git://<revspec>` URI buffer in a window per `opts.split`.
----`bufadd` dedups against existing buffers, so re-opening the same URI
+---`bufadd` dedups against existing buffers; `bufload` no-ops if loaded.
----reuses the buffer (and `bufload` no-ops). `read_uri` defaults to
----`bufhidden=wipe` (right for diff sides), but navigation buffers
----should persist across window closes, so override to `hide`.
 ---@param worktree string
 ---@param uri string
 ---@param sha string  written to `b:git_ref` so `<CR>` navigation in the buffer can resolve relative paths
@@ -283,7 +277,6 @@ local function open_uri(worktree, uri, sha, opts, default_ft)
     vim.b[buf].git_worktree = worktree
     vim.b[buf].git_ref = sha
     vim.fn.bufload(buf)
-    vim.bo[buf].bufhidden = "hide"
     if default_ft and vim.bo[buf].filetype == "" then
         vim.bo[buf].filetype = default_ft
     end

lua/git/sidebar.lua

@@ -495,7 +495,7 @@ end
 ---@return ow.Git.DiffSide
 local function absent_pane(worktree, path, kind)
     return {
-        buf = diff.empty_buf(),
+        buf = util.empty_buf(),
         name = string.format(
             "[absent %s] %s",
             kind,
@@ -865,7 +865,7 @@ local function open(worktree)
     end
 
     local previous_win = vim.api.nvim_get_current_win()
-    local bufnr, win = util.new_scratch({ split = "left", bufhidden = "wipe" })
+    local bufnr, win = util.new_scratch({ split = "left" })
     vim.bo[bufnr].filetype = "gitsidebar"
 
     vim.wo[win].number = false

lua/git/util.lua

@@ -44,6 +44,44 @@ function M.parse_revspec(revspec)
     return { stage = nil, path = path }
 end
 
+---@class ow.Git.ScratchOpts
+---@field name string?
+---@field bufhidden ("hide"|"wipe")?  defaults to "wipe"
+
+---Configure a fresh buffer as a read-only scratch and optionally name
+---it. Shared by `empty_buf` and `new_scratch`; the public functions
+---differ in whether they dedup-by-name or place the buffer in a window.
+---@param buf integer
+---@param opts ow.Git.ScratchOpts
+local function setup_scratch(buf, opts)
+    vim.bo[buf].buftype = "nofile"
+    vim.bo[buf].bufhidden = opts.bufhidden or "wipe"
+    vim.bo[buf].swapfile = false
+    vim.bo[buf].modifiable = false
+    vim.bo[buf].modified = false
+    if opts.name then
+        pcall(vim.api.nvim_buf_set_name, buf, opts.name)
+    end
+end
+
+---Build a read-only scratch buffer, optionally naming it. When `opts.name`
+---is set and a loaded buffer with that name already exists, returns it
+---instead of creating a duplicate.
+---@param opts ow.Git.ScratchOpts?
+---@return integer
+function M.empty_buf(opts)
+    opts = opts or {}
+    if opts.name then
+        local existing = vim.fn.bufnr(opts.name)
+        if existing ~= -1 and vim.api.nvim_buf_is_loaded(existing) then
+            return existing
+        end
+    end
+    local buf = vim.api.nvim_create_buf(false, true)
+    setup_scratch(buf, opts)
+    return buf
+end
+
 ---Place a buffer in the current window or a new split per `split`.
 ---`false` replaces the current buffer (drops a `'` mark first so `''`
 ---jumps back); a direction string opens a leftabove split; nil falls
@@ -62,12 +100,10 @@ function M.place_buf(buf, split)
     })
 end
 
----@class ow.Git.NewScratchOpts
+---@class ow.Git.NewScratchOpts : ow.Git.ScratchOpts
----@field name string?
----@field bufhidden ("hide"|"wipe")?  defaults to "hide"
 ---@field split (false|"above"|"below"|"left"|"right")? defaults to splitbelow-aware horizontal. `false` places the buffer in the current window (drops a `'` mark first so the user can jump back).
 
----Create a fresh non-modifiable scratch buffer and place it. Default split
+---Create a fresh read-only scratch buffer and place it. Default split
 ---direction is horizontal, honouring `splitbelow`. Caller flips
 ---`modifiable`, fills the buffer, and sets `filetype` once content lands.
 ---@param opts ow.Git.NewScratchOpts?
@@ -76,14 +112,7 @@ end
 function M.new_scratch(opts)
     opts = opts or {}
     local buf = vim.api.nvim_create_buf(false, true)
-    vim.bo[buf].buftype = "nofile"
+    setup_scratch(buf, opts)
-    vim.bo[buf].bufhidden = opts.bufhidden or "hide"
-    vim.bo[buf].swapfile = false
-    vim.bo[buf].modifiable = false
-    vim.bo[buf].modified = false
-    if opts.name then
-        pcall(vim.api.nvim_buf_set_name, buf, opts.name)
-    end
     return buf, M.place_buf(buf, opts.split)
 end