feat(git): route commit through GIT_EDITOR proxy

lua/git/commit.lua

@@ -1,3 +1,5 @@
+local editor = require("git.editor")
+local git = require("git")
 local log = require("log")
 local repo = require("git.repo")
 
@@ -6,89 +8,70 @@ local M = {}
 ---@param opts { amend: boolean? }?
 function M.commit(opts)
     local amend = opts and opts.amend or false
-    local gitdir, worktree = repo.resolve_cwd()
-    if not gitdir or not worktree then
+    local _, worktree = repo.resolve_cwd()
+    if not worktree then
         log.warning("not in a git repository")
         return
     end
-    local msg_path = vim.fs.joinpath(gitdir, "COMMIT_EDITMSG")
 
-    local initial = ""
+    local cmd = { "git", "commit" }
     if amend then
-        local result = vim.system(
-            { "git", "log", "-1", "--pretty=%B" },
-            { cwd = worktree, text = true }
-        ):wait()
-        if result.code == 0 then
-            initial = (result.stdout or ""):gsub("\n+$", "")
-        else
-            log.warning("git log -1 failed: %s", vim.trim(result.stderr or ""))
+        table.insert(cmd, "--amend")
+    end
+
+    local proxy_buf
+    editor.run(cmd, { cwd = worktree }, function(file_path, done)
+        local lines = {}
+        local f = io.open(file_path, "r")
+        if f then
+            for line in f:lines() do
+                table.insert(lines, line)
+            end
+            f:close()
         end
-    end
 
-    local f, err = io.open(msg_path, "w")
-    if not f then
-        log.error("failed to open %s: %s", msg_path, err or "")
-        return
-    end
-    f:write(initial)
-    f:close()
+        local buf = git.new_scratch({ name = file_path })
+        proxy_buf = buf
+        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
+        vim.bo[buf].filetype = "gitcommit"
 
-    local ok, err = pcall(vim.cmd.edit, vim.fn.fnameescape(msg_path))
-    if not ok then
-        log.error("failed to open %s: %s", msg_path, err or "")
-        return
-    end
-    local buf = vim.api.nvim_get_current_buf()
-    if vim.api.nvim_buf_get_name(buf) ~= msg_path then
-        -- `:edit` returned without surfacing an error but didn't actually
-        -- switch (defensive against an unusual ftplugin/autocmd path). Bail
-        -- before attaching a BufWriteCmd that would overwrite the wrong
-        -- file on the next `:w`.
-        log.error("failed to switch to %s", msg_path)
-        return
-    end
-    vim.bo[buf].filetype = "gitcommit"
+        vim.api.nvim_create_autocmd("BufWriteCmd", {
+            buffer = buf,
+            callback = function()
+                local out = vim.api.nvim_buf_get_lines(buf, 0, -1, false)
+                local fw, werr = io.open(file_path, "w")
+                if not fw then
+                    log.error("failed to write %s: %s", file_path, werr or "")
+                    return
+                end
+                fw:write(table.concat(out, "\n"))
+                fw:close()
+                vim.bo[buf].modified = false
+            end,
+        })
 
-    vim.api.nvim_create_autocmd("BufWriteCmd", {
-        buffer = buf,
-        callback = function()
-            local lines = vim.api.nvim_buf_get_lines(buf, 0, -1, false)
-            local fw, werr = io.open(msg_path, "w")
-            if not fw then
-                log.error("failed to write %s: %s", msg_path, werr or "")
-                return
-            end
-            fw:write(table.concat(lines, "\n"))
-            fw:close()
-            vim.bo[buf].modified = false
-
-            local cmd = { "git", "commit", "-F", msg_path }
-            if amend then
-                table.insert(cmd, "--amend")
-            end
-            vim.system(
-                cmd,
-                { cwd = worktree, text = true },
-                vim.schedule_wrap(function(result)
-                    if result.code ~= 0 then
-                        log.error(
-                            "git commit failed: %s",
-                            vim.trim(result.stderr or "")
-                        )
-                        return
-                    end
-                    local out = vim.trim(result.stdout or "")
-                    if out ~= "" then
-                        log.info("%s", out)
-                    end
-                    if vim.api.nvim_buf_is_valid(buf) then
-                        vim.api.nvim_buf_delete(buf, { force = true })
-                    end
-                end)
-            )
-        end,
-    })
+        vim.api.nvim_create_autocmd("BufWipeout", {
+            buffer = buf,
+            once = true,
+            callback = done,
+        })
+    end, function(result)
+        if proxy_buf and vim.api.nvim_buf_is_valid(proxy_buf) then
+            vim.api.nvim_buf_delete(proxy_buf, { force = true })
+        end
+        if result.code ~= 0 then
+            log.error("git commit failed: %s", vim.trim(result.stderr or ""))
+            return
+        end
+        local out = vim.trim(result.stdout or "")
+        if out ~= "" then
+            log.info("%s", out)
+        end
+    end)
 end
 
 return M