fix(git): keep index URI buffer in sync on save and reload

lua/git/diff.lua

@@ -24,14 +24,13 @@ end
 ---@param right integer
 ---@param vertical boolean
 function M.open(left, right, vertical)
-    local left_name = vim.api.nvim_buf_get_name(left)
     vim.cmd.normal({ "m'", bang = true })
     vim.api.nvim_set_current_buf(right)
-    vim.cmd.diffsplit({
+    vim.cmd.diffthis()
-        args = { left_name },
+    vim.api.nvim_open_win(left, true, {
-        mods = { split = "aboveleft", vertical = vertical, keepjumps = true },
+        split = vertical and "left" or "above",
-        magic = { file = false },
     })
+    vim.cmd.diffthis()
 end
 
 ---@param left_win integer

lua/git/init.lua

@@ -71,7 +71,7 @@ function M.init()
         pattern = "git://*",
         group = group,
         callback = function(args)
-            require("git.object").read_uri(args.buf)
+            require("git.object").read_uri(args.buf, { force = true })
         end,
     })
 

lua/git/object.lua

@@ -108,9 +108,6 @@ local function attach_index_writer(buf, r, path)
                     state.index_mode = mode
                 end
             end
-            -- Use the 3-arg form (mode sha path) instead of the comma
-            -- form (mode,sha,path), which doesn't survive paths
-            -- containing a comma.
             if
                 not util.exec({
                     "git",
@@ -123,6 +120,9 @@ local function attach_index_writer(buf, r, path)
             then
                 return
             end
+            if state then
+                state.sha = r:rev_parse(":" .. path, true)
+            end
             vim.bo[buf].modified = false
         end,
     })
@@ -146,7 +146,7 @@ end
 function M.buf_for(r, rev, content)
     local buf = vim.fn.bufadd(M.format_uri(rev))
     repo.bind(buf, r)
-    if content then
+    if content and not vim.api.nvim_buf_is_loaded(buf) then
         local state = r:state(buf) --[[@as -nil]]
         state.pending_content = content
     end
@@ -155,7 +155,9 @@ function M.buf_for(r, rev, content)
 end
 
 ---@param buf integer
-function M.read_uri(buf)
+---@param opts { force?: boolean }?
+function M.read_uri(buf, opts)
+    opts = opts or {}
     local name = vim.api.nvim_buf_get_name(buf)
     local rev = M.parse_uri(name)
     if not rev then
@@ -177,13 +179,15 @@ function M.read_uri(buf)
     ---@type string?
     local stdout = state.pending_content
     state.pending_content = nil
-    -- On a refresh tick (no caller-provided content), skip the re-read
-    -- when the rev still resolves to the same sha. Avoids re-firing
-    -- BufReadPost (and the LSP/treesitter re-attach storm) on every
-    -- fs-event for buffers whose content can't have changed.
     if stdout == nil then
         local rev_sha = r:rev_parse(rev_str, true)
-        if not rev_sha or rev_sha == state.sha then
+        if not rev_sha then
+            return
+        end
+        if
+            not opts.force
+            and (rev_sha == state.sha or vim.bo[buf].modified)
+        then
             return
         end
         stdout = util.exec(
@@ -231,10 +235,6 @@ function M.read_uri(buf)
     end
     vim.bo[buf].modified = false
 
-    -- Match on the inner path directly. `vim.filetype.add` patterns
-    -- don't work because Vim normalises `git://` filenames (cwd-prefix
-    -- + `://` -> `:/`) before matching, breaking any pattern keyed on
-    -- the raw scheme.
     if rev.path then
         local ft = vim.filetype.match({ filename = rev.path, buf = buf })
         if ft then